SC TO-T

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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE TO

TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) or 13(e)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934

Eon Labs, Inc.
(Name of Subject Company)

Novartis AG
Novartis Corporation
Zodnas Acquisition Corp.
(Name of Filing Persons—Offerors)

Common Stock, Par Value $0.01
(Title of Class of Securities)

29412E100
(CUSIP Number of Class of Securities)

George Miller
Head of Legal and General Affairs
Novartis AG
35 Lichtstrasse
CH-4002 Basel, Switzerland
41-61-324-1111
(Name, Address and Telephone Number of Person Authorized
to Receive Notices and Communications on Behalf of Filing Persons)

-Copies to-
Andrew R. Brownstein, Esq.
Trevor S. Norwitz, Esq.
Wachtell, Lipton, Rosen & Katz
51 West 52nd Street
New York, NY 10019
(212) 403-1000

CALCULATION OF FILING FEE

Transaction Valuation	Amount of Filing Fee
$977,098,158*	$195,420*

*

Estimated for purposes of calculating the amount of the filing fee only. The filing fee is calculated based on (i) the total number of shares of common stock, par value $0.01 of Eon Labs, Inc. outstanding as of May 5, 2005 according to Eon Labs, Inc.'s Quarterly Report filed with the Commission on Form 10-Q for the period ending March 31, 2005 (the "10-Q") (excluding (1) 60,000,000 shares of Eon Labs, Inc. common stock owned by Santo Holding (Deutschland) GmbH which are to be acquired outside the United States pursuant to a private agreement and (2) 137,122 shares of Eon Labs, Inc. common stock owned by Hexal AG which are to be indirectly acquired outside the United States pursuant to a private agreement) and (ii) the number of options to purchase shares of common stock of Eon Labs, Inc. outstanding as of March 31, 2005 according to the 10-Q. The amount of the filing fee, calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, equals ¹/50 of one percent of the aggregate cash offered by the bidder.

o

Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid: None.	Filing Party: Not applicable.
Form or Registration No.: Not applicable.	Date Filed: Not applicable.

o

Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

        Check the appropriate boxes below to designate any transactions to which the statement relates:

ý

third-party tender offer subject to Rule 14d-1.

o

issuer tender offer subject to Rule 13e-4.

o

going-private transaction subject to Rule 13e-3.

o

amendment to Schedule 13D under Rule 13d-2.

        Check the following box if the filing is a final amendment reporting the results of the tender offer: o

        This Tender Offer Statement on Schedule TO is filed by Novartis AG, a Swiss corporation, Novartis Corporation, a New York corporation and an indirect wholly owned subsidiary of Novartis AG ("Novartis US"), and Zodnas Acquisition Corp., a Delaware corporation ("Zodnas") and an indirect wholly owned subsidiary of Novartis US. This Schedule TO relates to the offer by Zodnas to purchase all of the outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation ("Eon"), for $31.00 per Share, net to the seller in cash, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated May 23, 2005 (the "Offer to Purchase"), and in the related Letter of Transmittal, copies of which are attached to this Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively (which, together with any amendments or supplements to the Offer to Purchase and the Letter of Transmittal, collectively constitute the "Offer").

        Pursuant to General Instruction F to Schedule TO, the information contained in the Offer to Purchase, including all schedules and annexes to the Offer to Purchase, is hereby expressly incorporated by reference in response to Items 1-9 and 11 of this Schedule TO and is supplemented by the information specifically provided for in this Schedule TO.

        The Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Zodnas, Eon and, for purposes of Section 12 thereof only, Novartis AG (the "Merger Agreement"), a copy of which is incorporated by reference herein as Exhibit (d)(1) to this Schedule TO; the Agreement for Purchase and Sale of Stock of Eon, by and between Novartis US, Santo Holding (Deutschland) GmbH ("Santo") and, for purposes of Section 10.12 thereof only, Novartis AG (the "Santo Agreement"), a copy of which is incorporated by reference herein as Exhibit (d)(2) to this Schedule TO; and the Confidentiality Agreement, by and between Novartis US and Eon, dated as of February 11, 2005, a copy of which is incorporated by reference herein as Exhibit (d)(3) to this Schedule TO, are each incorporated by reference in this Schedule TO.

Item 10.

        Not applicable.

Item 12. Exhibits

(a)(1)(A)	Offer to Purchase, dated May 23, 2005.
(a)(1)(B)	Form of Letter of Transmittal.
(a)(1)(C)	Form of Notice of Guaranteed Delivery.
(a)(1)(D)	Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(E)	Form of Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(F)	Guidelines for Certification of Taxpayer Identification Number (TIN) on Substitute Form W-9.
(a)(2)	Not applicable.
(a)(3)	Not applicable.
(a)(4)	Not applicable.
(a)(5)(A)	Text of Press Release issued by Novartis dated February 21, 2005, incorporated in this Schedule TO by reference to the Schedule TO filed by Novartis US, Novartis AG, and Zodnas on February 22, 2005.
(a)(5)(B)	Form of Summary Advertisement published in The Wall Street Journal on May 23, 2005.

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(a)(6)(A)	Complaint titled Ellen Wiehl v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(B)	Complaint titled Paulena Partners LLC v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(C)	Complaint titled Robert Kemp, IRRA v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(D)	Complaint titled Peter J. Calcagno v. Eon Labs, Inc. et al., filed on February 23, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(E)	Complaint titled Christopher Pizzo v. Novartis AG et al., filed on February 23, 2005, in the Supreme Court of the State of New York, County of New York.
(a)(6)(F)	Complaint titled Erste Sparinvest Kapitalanlagegesellschaft MBH v. Eon Labs, Inc. et al., filed on March 1, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(G)	Complaint titled Merl Huntsinger v. Eon Labs, Inc. et al., filed on March 1, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(H)	Complaint titled Jason Hung v. Eon Labs, Inc. et al., filed on March 3, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(b)	None.
(d)(1)	Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Zodnas, Eon and, for purposes of Section 12 thereof only, Novartis AG, incorporated in this Schedule TO by reference to Exhibit 2.2 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.
(d)(2)	Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and between Novartis US, Santo and, for purposes of Section 10.12 thereof only, Novartis AG, incorporated in this Schedule TO by reference to Exhibit 2.1 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.
(d)(3)	Confidentiality Agreement, by and between Novartis US and Eon, dated as of February 11, 2005, incorporated in this Schedule TO by reference to Exhibit 2.3 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.
(g)	None.
(h)	Not applicable.

Item 13. Information Required by Schedule 13e-3

        Not applicable.

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SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this Schedule TO is true, complete and correct.

Dated: May 23, 2005

Novartis AG
By:	/s/  RAYMUND BREU Name: Dr. Raymund Breu Title: Authorized Signatory
By:	/s/  URS BAERLOCHER Name: Urs Baerlocher Title: Authorized Signatory
Novartis Corporation
By:	/s/  MARTIN HENRICH Name: Martin Henrich Title: Executive Vice President
Zodnas Acquisition Corp.
By:	/s/  WAYNE P. MERKELSON Name: Wayne P. Merkelson Title: Vice President

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EXHIBIT INDEX

(a)(1)(A)	Offer to Purchase, dated May 23, 2005.
(a)(1)(B)	Form of Letter of Transmittal.
(a)(1)(C)	Form of Notice of Guaranteed Delivery.
(a)(1)(D)	Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(E)	Form of Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(F)	Guidelines for Certification of Taxpayer Identification Number (TIN) on Substitute Form W-9.
(a)(2)	Not applicable.
(a)(3)	Not applicable.
(a)(4)	Not applicable.
(a)(5)(A)	Text of Press Release issued by Novartis dated February 21, 2005, incorporated in this Schedule TO by reference to the Schedule TO filed by Novartis AG, Novartis US and Zodnas on February 22, 2005.
(a)(5)(B)	Form of Summary Advertisement published in The Wall Street Journal on May 23, 2005.
(a)(6)(A)	Complaint titled Ellen Wiehl v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(B)	Complaint titled Paulena Partners LLC v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(C)	Complaint titled Robert Kemp, IRRA v. Eon Labs, Inc. et al., filed on February 22, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(D)	Complaint titled Peter J. Calcagno v. Eon Labs, Inc. et al., filed on February 23, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(E)	Complaint titled Christopher Pizzo v. Novartis AG et al., filed on February 23, 2005, in the Supreme Court of the State of New York, County of New York.
(a)(6)(F)	Complaint titled Erste Sparinvest Kapitalanlagegesellschaft MBH v. Eon Labs, Inc. et al., filed on March 1, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(G)	Complaint titled Merl Huntsinger v. Eon Labs, Inc. et al., filed on March 1, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(a)(6)(H)	Complaint titled Jason Hung v. Eon Labs, Inc. et al., filed on March 3, 2005, in the Chancery Court of the State of Delaware, County of New Castle.
(b)	None.
(d)(1)	Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Zodnas, Eon and, for purposes of Section 12 thereof only, Novartis AG, incorporated in this Schedule TO by reference to Exhibit 2.2 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.

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(d)(2)	Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and between Novartis US, Santo and, for purposes of Section 10.12 thereof only, Novartis AG, incorporated in this Schedule TO by reference to Exhibit 2.1 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.
(d)(3)	Confidentiality Agreement, by and between Novartis US and Eon, dated as of February 11, 2005, incorporated in this Schedule TO by reference to Exhibit 2.3 to the Schedule 13D filed by Novartis US, Novartis AG and Zodnas on March 2, 2005.
(g)	None.
(h)	Not applicable.

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SIGNATURE
EXHIBIT INDEX

EX-99.(A)(1)(A)

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Exhibit (a)(1)(A)

OFFER TO PURCHASE FOR CASH
ANY AND ALL OUTSTANDING SHARES OF
COMMON STOCK, PAR VALUE $0.01 PER SHARE
OF
Eon Labs, Inc.
AT
$31.00 NET PER SHARE
BY
Zodnas Acquisition Corp.

an indirect wholly owned subsidiary
OF
Novartis AG

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00
MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

        Zodnas Acquisition Corp. ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation ("Novartis US"), an indirect wholly owned subsidiary of Novartis AG, is offering (the "Offer") to acquire any and all outstanding shares of common stock, par value $0.01 per share of Eon Labs, Inc. (the "Company"). The Offer is being made pursuant to an Agreement and Plan of Merger, dated as of February 20, 2005 (the "Merger Agreement"), by and among Novartis US, Purchaser, the Company and, for purposes of Section 10.12 thereof only, Novartis AG. Under the Merger Agreement, Purchaser will be merged with and into the Company (the "Merger") if a majority of the outstanding shares of Company common stock (other than the Shares owned by Santo Holding (Deutschland) GmbH ("Santo")) are tendered into the Offer.

        The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designees of the 60,000,000 shares of Company common stock owned by Santo, representing approximately 67.5% of the outstanding equity interest in the Company, pursuant to the Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and among Novartis US, Santo and, for purposes of Section 12 thereof only, Novartis AG (the "Santo Agreement," and such stock purchase, the "Santo Purchase"); and (2) satisfaction of all applicable legal requirements for consummating the Offer. See Section 15. Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase, including consummation of the transactions contemplated by the Hexal Agreement (described in the Introduction), is indirectly a condition to the Offer. See Subsection 12(c).

        The existence or satisfaction of any of the conditions to the Offer will be determined by Novartis AG, Novartis US and Purchaser. Any and all of the conditions to the Offer may be waived (to the extent legally permissible) by Novartis AG, Novartis US or Purchaser in their sole discretion. See Section 15. The Offer is not conditioned on obtaining financing. See Section 13.

Both the Company's Board of Directors and a special committee of the Company's Board of Directors consisting of independent directors not affiliated with Santo (the "Special Committee") have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the Delaware General Corporation Law, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders and (iv) taken all other action within the Company Board of Directors' and the Special Committee's power to render Section 203 of the Delaware General Corporation Law, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger.

The Dealer Manager for the Offer is:
Goldman, Sachs & Co.

        If you wish to tender all or any part of your shares of Company common stock prior to the expiration date of the Offer, you should either (1) complete and sign the Letter of Transmittal (or a facsimile thereof) in accordance with the instructions in the Letter of Transmittal included with this Offer to Purchase, have your signature thereon guaranteed if required by Instruction 1 of the Letter of Transmittal, mail or deliver the Letter of Transmittal (or such facsimile thereof) and any other required documents to ComputerShare Trust Company, Inc., the Depositary for the Offer, and either deliver the certificates for such shares to the Depositary for the Offer along with the Letter of Transmittal (or a facsimile thereof) or deliver such shares pursuant to the procedures for book-entry transfers set forth in Section 4 of this Offer to Purchase, or (2) request your broker, dealer, commercial bank, trust company or other nominee to effect the transaction for you. If you have shares of Company common stock registered in the name of a broker, dealer, commercial bank, trust company or other nominee, you must contact such broker, dealer, commercial bank, trust company or other nominee if you desire to tender your shares of Company common stock.

        If you desire to tender your shares of Company common stock and your certificates for such shares are not immediately available, or you cannot comply with the procedures for book-entry transfers described in this Offer to Purchase on a timely basis, you may tender such shares by following the procedures for guaranteed delivery set forth in Section 4.

        Questions or requests for assistance may be directed to Georgeson Shareholder Communications Inc., the Information Agent, at the address and telephone number set forth on the back cover of this Offer to Purchase. You can also obtain additional copies of this Offer to Purchase, the Letter of Transmittal and the Notice of Guaranteed Delivery from the Information Agent or your broker, dealer, commercial bank, trust company or other nominee.

        A summary of the principal terms of the Offer appears on pages 4-10 of this Offer to Purchase.

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TABLE OF CONTENTS

			Page
SUMMARY TERM SHEET			4
FORWARD-LOOKING STATEMENTS			11
INTRODUCTION			12
THE OFFER			15
	1.	Terms of the Offer	15
	2.	Extension of Tender Period; Termination; Amendment	15
	3.	Acceptance for Payment and Payment	17
	4.	Procedure for Tendering Shares	18
	5.	Withdrawal Rights	21
	6.	Certain U.S. Federal Income Tax Consequences	22
	7.	Price Range of Company Common Stock; Dividends	23
	8.	Effect of the Offer on the Market for the Company Common Stock; Registration Under the Exchange Act; Margin Regulations	23
	9.	Certain Information Concerning the Company	25
	10.	Certain Information Concerning Novartis AG, Novartis US and Purchaser	25
	11.	Background of the Offer; Past Contacts or Negotiations with the Company	27
	12.	Purpose of the Offer; the Merger Agreement; the Santo Agreement; Statutory Requirements; Appraisal Rights; "Going Private" Transactions; Plans for the Company	30
	13.	Source and Amount of Funds	42
	14.	Dividends and Distributions	42
	15.	Conditions to the Offer	43
	16.	Certain Legal Matters; Regulatory Approvals	43
	17.	Fees and Expenses	45
	18.	Legal Proceedings	46
	19.	Miscellaneous	48
SCHEDULE I			49

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SUMMARY TERM SHEET

        Zodnas Acquisition Corp. ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation ("Novartis US"), an indirect wholly owned subsidiary of Novartis AG, is offering (the "Offer") to acquire any and all of the outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc. (the "Company") for $31.00 per Share, net to you in cash, without interest (the "Offer Price") pursuant to an Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Purchaser, the Company and for purposes of Section 10.12 thereof only, Novartis AG (the "Merger Agreement"). Pursuant to the Agreement for Purchase and Sale of Stock, dated February 20, 2005, by and between Novartis US, Santo Holding (Deutschland) GmbH ("Santo") and, for purposes of Section 12 thereof only, Novartis AG (the "Santo Agreement"), Santo has agreed to sell, and Novartis US has agreed to acquire, all 60,000,000 Shares owned by Santo (the "Santo Shares") for €1,300,000,000, plus interest from January 1, 2005 through the closing under the Santo Agreement at an annualized rate of 1% above the three-month Euro Interbank Offering Rate (EURIBOR). Pursuant to the Share and Partnership Interest Sale and Transfer Agreement (the "Hexal Agreement"), by and among Novartis (Deutschland) GmbH ("Novartis Deutschland"), Novartis AG (as guarantor) and certain members of the Strüngmann family, dated as of February 16-17, 2005, relating to the acquisition of shares in A+T Vermögensverwaltung GmbH as well as partnership interests in A+T Holding GmbH & Co. KG, Novartis Deutschland will acquire 137,122 Shares currently owned by Hexal AG ("Hexal"), a wholly owned subsidiary of A+T Vermögensverwaltung GmbH, which represents approximately 0.2% of the outstanding Shares. Although Purchaser is offering to acquire any and all Shares, the Shares currently owned by Santo and Hexal will not be tendered into the Offer. Therefore, Purchaser is effectively offering pursuant to the Offer to acquire any and all Shares not owned by Santo or Hexal (all Shares other than the Santo Shares, the "Public Shares").

        The following are some of the questions you as a stockholder of the Company may have, and answers to those questions. This Summary Term Sheet is not meant to be a substitute for the information contained in the remainder of this Offer to Purchase and the related Letter of Transmittal, and the information contained in this Summary Term Sheet is qualified in its entirety by the more detailed descriptions and explanations contained in this Offer to Purchase and the related Letter of Transmittal. We urge you to carefully read this Offer to Purchase and the related Letter of Transmittal in their entirety prior to making any decision regarding whether to tender your Shares.

Who is offering to purchase my Shares?

Purchaser is Zodnas Acquisition Corp., a corporation formed solely for the purpose of making the Offer. Purchaser is an indirect wholly owned subsidiary of Novartis US, which is an indirect wholly owned subsidiary of Novartis AG. Novartis AG's group of companies is principally engaged in the development, manufacture and marketing of prescription medicines. Novartis US indirectly owns most of the companies of the Novartis AG group operating in the U.S. See the Introduction and Section 10.

How many Shares is Purchaser seeking to purchase and at what price?

Purchaser is effectively offering to purchase any and all of the Shares not owned by Santo or Hexal, meaning that Purchaser is effectively offering to purchase approximately 32.3% of the outstanding Shares. Pursuant to the Santo Agreement, Novartis US agreed to acquire approximately 67.5% of the outstanding Shares directly from Santo, the controlling stockholder of the Company. In addition, Novartis Deutschland will indirectly acquire 137,122 Shares, or approximately 0.2% of the outstanding Shares, pursuant to the Hexal Agreement.

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	Purchaser is offering to pay $31.00 per Share, net to you in cash, without interest. This price represents approximately a 25% premium to the reported closing price of Shares on the Nasdaq National Market on February 4, 2005 of $24.75, the last trading day prior to media speculation about a possible takeover of the Company. As of February 18, 2005, the last trading day prior to Novartis US's announcement that it was seeking to enter into a business combination with the Company, the closing price of a Share on the Nasdaq National Market was $27.92, and as of May 20, 2005, the last trading day prior to the date of this Offer to Purchase, the closing price of a Share on the Nasdaq National Market was $30.15. See the Introduction and Section 7.
What price is Novartis US paying for the Santo Shares?	Novartis US is acquiring the controlling block of Santo Shares for €1,300,000,000, plus interest from January 1, 2005 through the closing under the Santo Agreement at an annualized rate of 1% above the three-month Euro Interbank Offering Rate (EURIBOR). Based on the dollar-to-euro exchange rate and the interest rate provided for in the Santo Agreement, both as of the close of business on February 18, 2005 (the last business day prior to the date on which the Santo Agreement was signed), including accrued interest through the date on which the Santo Agreement was signed, the €1,300,000,000 price represented approximately $28.45 per Share as of such date. Based on the exchange rate and the interest rate provided for in the Santo Agreement, both as of the close of business on May 20, 2005 (the last business day prior to the date of this Offer to Purchase) and including interest accrued through May 22, 2005 (the day prior to the date of this Offer to Purchase), Novartis US is paying approximately $27.54 per Santo Share.
Do I have to pay any brokerage or similar fees to tender?	If you are the record owner of your Shares and you tender Shares in the Offer, you will not have to pay any brokerage or similar fees. However, if you own your Shares through a broker or other nominee, and your broker tenders your Shares on your behalf, your broker or nominee may charge you a fee for doing so. You should consult your broker or nominee to determine whether any charges will apply. See the Introduction.
Why is Purchaser making this Offer?	Purchaser is making the Offer to acquire all of the Shares not owned by Santo or Hexal. Under the Merger Agreement, if a majority of the Public Shares are tendered in the Offer, Novartis US is obligated to cause a merger between Purchaser and the Company in which all remaining Company stockholders will receive $31.00 per Share (the "Merger").

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What is Novartis US's current relationship with the Company?	Other than pursuant to the transactions and agreements described in this Offer to Purchase and ordinary course patent litigation that is common in the pharmaceutical industry, Novartis US currently has no relationship with the Company. See Section 11 and Section 12.
What are the most important conditions to the Offer?	The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designee of the Santo Shares pursuant to the Santo Agreement, and (2) satisfaction of all applicable legal requirements for consummating the Offer. See Section 15.
	Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the purchase of the Santo Shares pursuant to the Santo Agreement (the "Santo Purchase"), each of the conditions to the consummation of the Santo Purchase is indirectly a condition to the Offer. The consummation of the Santo Purchase is conditioned upon, among other things, the transactions contemplated by the Hexal Agreement having been consummated or being consummated contemporaneously with the closing of the Santo Purchase. See Subsection 12(c).
Does Purchaser have the financial resources to pay for the Shares it is offering to purchase?	Yes. The Offer is not conditioned on Novartis AG, Novartis US or Purchaser obtaining financing. Novartis AG or an affiliate of Novartis AG will contribute or otherwise advance a sufficient amount of funds to Purchaser to consummate the Offer. See Section 13.
How long do I have to decide whether to tender into the Offer?	You have until the expiration date of the Offer to tender your Shares. The Offer currently is scheduled to expire at 12:00 midnight, New York City time, on June 20, 2005.
Can the Offer be extended and, if so, under what circumstances?	Purchaser is required to extend the Offer if the conditions to the Offer are not satisfied by the expiration date. In addition, Purchaser may extend the Offer in its discretion for an additional period under certain circumstances as described in Section 2. If the Offer is extended, Purchaser will issue a press release announcing the extension at or before 9:00 a.m., New York City time on the first business day following the date the Offer was scheduled to expire. See Section 2.

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	Following the expiration of the Offer, Purchaser may choose to provide a "subsequent offering period" in accordance with applicable law, although Purchaser and Novartis US currently do not intend to do so. A subsequent offering period, if one is included, will be an additional period of time beginning after Purchaser has purchased all Shares tendered during the Offer, during which, if you did not tender any of your Shares during the Offer, you may tender them and receive the Offer Price. You may not withdraw any Shares you tender during a subsequent offering period, if one is included. See Section 1.
How do I accept the Offer and tender my Shares?	To tender your Shares, you must completely fill out the enclosed Letter of Transmittal and deliver it, along with your share certificates and any other documents required by the Letter of Transmittal, to ComputerShare Trust Company, Inc. (the "Depositary"), prior to the expiration of the Offer. If your Shares are held in street name (i.e., through a broker, dealer or other nominee), your Shares can be tendered by your nominee through the Depositary. If you cannot deliver all necessary documents to the Depositary in time, you may be able to complete and deliver to the Depositary, in lieu of the missing documents, the enclosed Notice of Guaranteed Delivery, provided you are able to comply fully with its terms. See Section 4.
If I accept the Offer, when will I get paid?	If the conditions to the Offer are satisfied and Purchaser completes the Offer and accepts your Shares for payment, you will receive payment for your tendered Shares as promptly as practicable following the expiration of the Offer. See Section 3.
Can I withdraw my previously tendered Shares?	You may withdraw a portion of or all your tendered Shares by delivering written, telegraphic or facsimile notice to the Depositary at any time prior to the expiration of the Offer. Also, if Purchaser has not accepted your Shares for payment by July 21, 2005, you can withdraw your tendered Shares at any time after that date until Purchaser accepts your Shares for payment. Once Shares are accepted for payment, they cannot be withdrawn. Withdrawal rights will not apply to any Shares tendered in a subsequent offering period, if one is included. See Section 5.
What does the Company Board of Directors think of this Offer?	Both the Company's Board of Directors (the "Company Board") and a special committee of the Company Board consisting of independent directors not affiliated with Santo (the "Special Committee") have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the Delaware General Corporation Law ("DGCL"), (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders and (iv) taken all other action within the Company Board's and the Special Committee's power to render Section 203 of the DGCL, if applicable, inapplicable to any of the Santo Purchase, the Offer or the Merger (although Novartis AG, Novartis US and Purchaser do not believe that Section 203 of the DGCL is applicable to any of the Santo Purchase, the Offer or the Merger). See the Introduction and Subsection 12(b).

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Merrill Lynch & Co., financial advisor to the Special Committee (the "Special Committee Financial Advisor"), has delivered to the Special Committee a written opinion, dated February 20, 2005, to the effect that, as of that date, and based upon and subject to the factors and assumptions stated in its opinion, the consideration to be received in the Offer and the Merger by holders of Public Shares is fair, from a financial point of view, to such stockholders. A copy of the Special Committee Financial Advisor's opinion is included with the Company's Solicitation/Recommendation Statement on Schedule 14D-9 (the "Schedule 14D-9"), and holders of Public Shares are urged to read the opinion in its entirety for a description of the assumptions made, matters considered and limitations of the review undertaken by the Special Committee Financial Advisor. See the Introduction and Subsection 12(e).

If I do not tender, what will happen to my Shares?

If a majority of the Public Shares are tendered in the Offer, under the Merger Agreement, Novartis US is obligated to cause a merger between Purchaser and the Company in which all outstanding Shares that are not purchased in the Offer (other than Shares owned by the Company or by Novartis AG or any of its subsidiaries) will be cancelled and automatically converted into the right to receive the Offer Price in cash, without interest. If the Merger takes place, Company stockholders who do not tender in the Offer will receive the same amount of cash per Share that they would have received had they tendered their Shares in the Offer, subject to their right to pursue appraisal rights under Delaware law. Therefore, if the Merger takes place and you do not perfect your appraisal rights, the only difference to you between tendering your Shares in the Offer and not tendering your Shares in the Offer is that you will be paid earlier if you tender your Shares in the Offer. If, following the consummation of the Santo Purchase and the Offer, Purchaser and Novartis US own at least 90% of the Shares, the parties to the Merger Agreement will cause the Merger to occur without a vote of the Company's stockholders pursuant to Section 253 of the DGCL. See Subsection 12(b).

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	If less than a majority of the Public Shares are tendered in the Offer, until the earlier of February 11, 2006 or until Novartis US and its subsidiaries own 90% of the Shares, Purchaser and Novartis US will not be permitted to effect a merger between Purchaser and the Company without the approval of a majority of the then-outstanding Public Shares. However, following the Offer, Purchaser may make acquisitions of Shares that are voluntary to the holders, such as by means of open market purchases or tender offers.
	If following the Offer, the Merger does not take place, there may be a diminished or inactive trading market for the Shares, which may negatively affect the value of the remaining Shares.
	Following the completion of the Offer, Purchaser and Novartis US are required by the Merger Agreement to use reasonable best efforts until the earlier of the consummation of the Merger and February 11, 2006 to keep the Shares quoted for trading on the Nasdaq National Market as long as the Company is required to be registered under the Securities Exchange Act of 1934, as amended (including the rules and regulations promulgated thereunder), and satisfies the Nasdaq National Market's listing standards (other than standards entirely within the Company's control). However, following the completion of the Offer, the number of Shares not owned by Purchaser, Novartis US or our affiliates may no longer satisfy the listing requirements of the Nasdaq National Market or any national securities exchange, and the Company may cease making filings with the Securities and Exchange Commission (the "SEC") or otherwise cease being required to comply with the SEC's rules relating to publicly held companies. See Section 8.
Are appraisal rights available in either the Offer or the proposed subsequent Merger?	Appraisal rights are not available in the Offer. After the Offer, if the Merger takes place, appraisal rights will be available to holders of Shares who do not vote in favor of the Merger, subject to and in accordance with Delaware law. A holder of Shares must properly perfect its right to seek appraisal under Delaware law in connection with the Merger in order to exercise appraisal rights. The value you would receive if you perfect appraisal rights could be more or less than the price per Share to be paid in the Merger. See Subsection 12(e).
What are the federal income tax consequences of the proposed transactions?	The receipt of cash in the Offer or the Merger in exchange for Shares will be a taxable transaction for U.S. federal income tax purposes and may also be a taxable transaction under applicable state, local or foreign income or other tax laws. You should consult your tax advisor about the particular effect the proposed transactions will have to you. See Section 6.

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What is the market value of my Shares as of a recent date?

On February 4, 2005, the last trading day prior to media speculation about a possible takeover of the Company, the reported closing price on the Nasdaq National Market for the Shares was $24.75. The Offer Price, therefore, represents approximately a 25% premium to the reported closing price on the last trading day prior to media speculation about a possible takeover of the Company. On February 18, 2005, the last trading day before the public announcement of Novartis US's intention to pursue a business combination with the Company, the Shares closed on the Nasdaq National Market at $27.92 per Share. On May 20, 2005, the last trading day before the date of this Offer to Purchase, the Shares closed on the Nasdaq National Market at $30.15 per Share. You should obtain a recent quotation for your Shares prior to deciding whether or not to tender your Shares in the Offer. See Section 7.

Whom can I call with questions?

You can call Georgeson Shareholder Communications Inc. at (877) 278-4774 (toll free) with any questions you may have. Georgeson Shareholder Communications Inc. is acting as the Information Agent and Goldman, Sachs & Co. is acting as the Dealer Manager for the Offer. See the back cover of this Offer to Purchase for further details.

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FORWARD-LOOKING STATEMENTS

        Some of the statements in this Offer to Purchase constitute forward-looking statements that do not directly or exclusively relate to historical facts, including statements relating to the views of Novartis US or Purchaser regarding the business of the Company and the benefits of tendering your Shares and of combining the business of the Company with the business of Novartis US. The Private Securities Litigation Reform Act of 1995 provides a "safe harbor" for certain forward-looking statements as long as they are identified as forward-looking and are accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from the expectations expressed or implied in the forward-looking statements. When used in this Offer to Purchase, the words "may," "will," "should," "expect," "plan," "anticipate," "believe," "estimate," "predict," "intend," "potential" or "continue," or the negative of these terms, and other similar expressions are intended to identify forward-looking statements. The forward-looking statements made in this Offer to Purchase reflect Novartis US and Purchaser's current intentions, plans, expectations, assumptions and beliefs about future events and are subject to risks, uncertainties and other factors, many of which are outside of Novartis US and Purchaser's control. Because actual results could differ materially from Novartis US and Purchaser's current intentions, plans, expectations, assumptions and beliefs about the future, you are urged not to rely on forward-looking statements in this Offer to Purchase and to view all forward-looking statements made in this Offer to Purchase with caution. Neither Novartis US nor Purchaser undertakes any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. You should assume that the information appearing in this Offer to Purchase is accurate as of the date hereof only.

        Forward-looking statements are not guarantees of future performance or results and involve considerable risks and uncertainties, and actual results or developments may differ materially from the expectations expressed or implied in the forward-looking statements as a result of various factors, including, but not limited to, those discussed below. In connection with this Offer to Purchase, known risks include, but are not limited to, (a) the inability to consummate the Santo Purchase or to consummate the transactions contemplated by the Hexal Agreement, (b) the inability to satisfy legal requirements for consummating the Offer, and (c) the inability to consummate the Offer for any other reason, including termination or amendment of the Offer in the event that the Special Committee, Novartis US and Purchaser reach an agreement or understanding to terminate or amend the Offer.

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To: All Holders of Shares of Common Stock of Eon Labs, Inc.

INTRODUCTION

        Zodnas Acquisition Corp. ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation ("Novartis US"), an indirect wholly owned subsidiary of Novartis AG, is offering (the "Offer") to acquire any and all of the outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc. (the "Company") for $31.00 per Share, net to the seller in cash, without interest (the "Offer Price"). Pursuant to the Agreement for Purchase and Sale of Stock, dated February 20, 2005, by and between Novartis US, Santo Holding (Deutschland) GmbH ("Santo") and, for purposes of Section 12 thereof only, Novartis AG (the "Santo Agreement"), Santo has agreed to sell, and Novartis US has agreed to acquire, all 60,000,000 Shares owned by Santo (the "Santo Shares") for €1,300,000,000, plus interest from January 1, 2005 through the closing under the Santo Agreement at an annualized rate of 1% above the three-month Euro Interbank Offering Rate (EURIBOR). Pursuant to the Share and Partnership Interest Sale and Transfer Agreement (the "Hexal Agreement"), by and among Novartis (Deutschland) GmbH ("Novartis Deutschland"), Novartis AG (as guarantor) and certain members of the Strüngmann family, dated as of February 16-17, 2005, relating to the acquisition of shares in A+T Vermögensverwaltung GmbH as well as partnership interests in A+T Holding GmbH & Co. KG, Novartis Deutschland will indirectly acquire 137,122 Shares currently owned by Hexal AG ("Hexal"), a wholly owned subsidiary of A+T Vermögensverwaltung GmbH, which represents approximately 0.2% of the outstanding Shares. Although Purchaser is offering to acquire any and all Shares, the Shares currently owned by Santo and Hexal will not be tendered into the Offer. Therefore, Purchaser is effectively offering pursuant to the Offer to acquire any and all Shares not owned by Santo or Hexal (all Shares other than the Santo Shares, the "Public Shares"). For a description of the Santo Agreement, see Subsection 12(c)—"The Santo Agreement."

        Upon the terms and subject to the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any such extension or amendment), Purchaser will purchase all Shares validly tendered and not withdrawn in accordance with the procedures set forth in Section 4—"Procedure for Tendering Shares" on or prior to the Expiration Date. "Expiration Date" means 12:00 Midnight, New York City time, on June 20, 2005, unless the period of time for which the initial offering period of the Offer is open is extended, in which case "Expiration Date" will mean the latest time and date on which the Offer, as so extended, will expire. Purchaser may, in compliance with applicable law and Section 1.1 of the Merger Agreement, provide a subsequent offering period, which would be an additional period following the completion of the Offer of three to twenty business days during which Company stockholders would be able to tender Shares not tendered in the Offer. See Section 1—"Terms of the Offer."

        Stockholders who have Shares registered in their own names and tender directly to ComputerShare Trust Company, Inc., the depositary for the Offer (the "Depositary"), will not be obligated to pay brokerage fees, commissions or, except as set forth in Instruction 6 of the Letter of Transmittal, transfer taxes on the sale of their Shares pursuant to the Offer. Stockholders with Shares held in street name by a broker or other nominee should consult with their broker or nominee to determine if they charge any transaction fees. However, tendering stockholders who fail to complete and sign the Substitute Form W-9 included in the Letter of Transmittal may be subject to a required backup United States federal income tax withholding of 28% of the gross proceeds payable to such stockholder. We will pay all charges and expenses of the Depositary, Goldman, Sachs & Co. (the "Dealer Manager") and Georgeson Shareholder Communications Inc. (the "Information Agent") incurred in connection with the Offer. See Section 17—"Fees and Expenses."

        Purchaser is making the Offer pursuant to the Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Purchaser, the Company and, for purposes of

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Section 10.12 thereof only, Novartis AG (the "Merger Agreement"). Following the consummation of the Offer and the satisfaction or waiver of certain conditions, if a majority of the Public Shares are tendered in the Offer, Novartis US is obligated to and will cause a merger of Purchaser and the Company, with the Company continuing as the surviving corporation (the "Merger"). If following consummation of the Offer, Novartis US, Purchaser and any other subsidiary of Novartis US collectively own at least 90% of the total outstanding Shares, the parties to the Merger Agreement will cause the Merger to occur without a vote of the Company's stockholders pursuant to Section 253 of the Delaware General Corporation Law (the "DGCL"). In the Merger, each outstanding Share that is not owned by the Company directly as treasury stock or by Novartis AG or any of its subsidiaries (other than in a representative or fiduciary capacity) and other than Shares held by Company stockholders that perfect their appraisal rights under the DGCL will be cancelled and automatically converted into the right to receive the Offer Price in cash, without interest (the "Merger Consideration").

        The Merger Agreement further provides that if less than a majority of the Public Shares are tendered in the Offer (inclusive of any Shares tendered during any subsequent offering period, if one is offered), the standstill provisions of the Confidentiality Agreement, dated as of February 11, 2005, by and between Novartis US and the Company (the "Confidentiality Agreement") will be amended to provide that, although under the Confidentiality Agreement Novartis US and its affiliates may not acquire additional Public Shares by means of a merger until February 11, 2006, Novartis US and its subsidiaries will be permitted to make acquisitions of Shares that are voluntary to the holders of Shares (such as by means of legally permissible open market purchases or additional tender offers) and may consummate a merger or other business combination with the Company prior to February 11, 2006, only if: (1) a majority of the then-outstanding Public Shares approve such transaction; or (2) Novartis US and its subsidiaries at such time own 90% or more of the total outstanding Shares, provided that the price per Share paid in any such transaction described in (2) above is at least equal to the Offer Price. For further details on the Merger Agreement, see Subsection 12(b)—"The Merger Agreement". For a description of the principal United States federal income tax consequences of the sale of Shares in the Offer (including any subsequent offering period) and the Merger, see Section 6—"Certain U.S. Federal Income Tax Consequences."

        Novartis US will purchase the Santo Shares pursuant to the Santo Agreement contemporaneously with or immediately after the closing of the Offer (such purchase, the "Santo Purchase"). For a description of the Santo Agreement, see Subsection 12(c)—"The Santo Agreement."

Both the Company's Board of Directors (the "Company Board") and a special committee of the Company Board consisting of independent directors not affiliated with Santo (the "Special Committee") have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the DGCL, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders and (iv) taken all other action within the Company Board's and the Special Committee's power to render Section 203 of the DGCL, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger.

        Merrill Lynch & Co., financial advisor to the Special Committee (the "Special Committee Financial Advisor"), has delivered to the Special Committee a written opinion, dated February 20, 2005, to the effect that, as of that date, and based upon and subject to certain matters stated in its opinion, the consideration to be received in the Offer and the Merger by the holders of Public Shares is fair, from a financial point of view, to such stockholders. A copy of the Special Committee Financial Advisor's opinion is included with the Company's Solicitation/Recommendation Statement

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on Schedule 14D-9 (the "Schedule 14D-9"), and holders of Public Shares are urged to read the opinion in its entirety for a description of the assumptions made, matters considered and limitations of the review undertaken by the Special Committee Financial Advisor.

        The Company has advised Novartis US and Purchaser that, to the best of the Company's knowledge, each executive officer, director, affiliate and subsidiary of the Company (other than Dr. Thomas Strüngmann, Santo and Hexal) currently intends, subject to compliance with applicable law, including Section 16(b) of the Securities Exchange Act of 1934, as amended (including the rules and regulations promulgated thereunder, the "Exchange Act"), to tender all Shares held of record or beneficially owned by such person to Purchaser in the Offer (other than Shares that they have the right to purchase by exercising stock options).

        The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designee of the Santo Shares pursuant to the Santo Agreement, and (2) satisfaction of all legal requirements for consummating the Offer. See Subsection 12(c)—"The Santo Agreement" and Section 15—"Conditions to the Offer."

        The existence or satisfaction of any of the conditions to the Offer will be determined by Novartis AG, Novartis US and Purchaser. Any and all of the conditions to the Offer may be waived (to the extent legally permissible) by Novartis AG, Novartis US or Purchaser in their sole discretion. See Subsection 12(c)—"The Santo Agreement" and Section 15—"Conditions to the Offer." The Offer is not conditioned on obtaining financing. See Section 13—"Source and Amount of Funds."

        THE OFFER IS CONDITIONED UPON THE FULFILLMENT OF THE CONDITIONS DESCRIBED IN SECTION 15—"CONDITIONS TO THE OFFER." THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

        THIS OFFER TO PURCHASE AND THE RELATED LETTER OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION, AND YOU SHOULD CAREFULLY READ BOTH IN THEIR ENTIRETY BEFORE YOU MAKE A DECISION WITH RESPECT TO THE OFFER.

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THE OFFER

1.     Terms of the Offer.

        On the terms and subject to the conditions set forth in this Offer to Purchase (including, if the Offer is extended or amended, the terms and conditions of such extension or amendment), we will accept for payment and pay for any and all Shares that are validly tendered prior to the Expiration Date and not properly withdrawn.

        The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designee of the Santo Shares pursuant to the Santo Agreement, and (2) satisfaction of all requirements of any applicable United States or foreign federal, state or local law, statute, ordinance, rule, regulation, judgment, order, injunction, decree, agency requirement, license or permit of any United States or foreign federal, state or local governmental or regulatory authority, agency, commission, body or other governmental entity (the "Tender Offer Conditions"). See Section 15—"Conditions to the Offer." Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase, including consummation of the transactions contemplated by the Hexal Agreement, is effectively an indirect condition to the Offer. See Subsection 12(c)—"The Santo Agreement—Closing Conditions."

        Subject to the Merger Agreement and applicable rules and regulations, if any such condition is not satisfied, we may: (a) terminate the Offer and return all tendered Shares; (b) extend the Offer and, subject to certain conditions and to your withdrawal rights as set forth in Section 5—"Withdrawal Rights," retain all Shares until the Expiration Date of the Offer as so extended; or (c) waive the unsatisfied condition (to the extent legally permissible) and accept for payment all Shares so tendered. For a description of our right to extend, terminate, amend or delay the Offer, see Section 2—"Extension of Tender Period; Termination; Amendment" and Section 15—"Conditions to the Offer."

        In accordance with Exchange Act Rule 14d-11, Purchaser expressly reserves the right to provide a subsequent offering period of between three and twenty business days (as such term is defined under Exchange Act Rule 14d-1(g)(3)) following the Expiration Date. If included, a subsequent offering period would be an additional period of time, following the expiration of the Offer and the purchase of Shares in the Offer, during which stockholders may tender any Shares not tendered in the Offer. A subsequent offering period, if one is included, is not an extension of the Offer, which already would have been completed.

        Novartis US and Purchaser do not currently intend to include a subsequent offering period, although Novartis US and Purchaser reserve the right to do so in their sole discretion. As permitted by Exchange Act Rule 14d-7, no withdrawal rights will apply to Shares tendered during a subsequent offering period and no withdrawal rights will apply during the subsequent offering period with respect to Shares tendered in the Offer and accepted for payment. If Novartis US and Purchaser, in their discretion, elect to include a subsequent offering period, Purchaser will pay the same applicable consideration to stockholders tendering Shares in the Offer or in the subsequent offering period. If Novartis US and Purchaser elect to provide a subsequent offering period, they will provide an announcement to that effect to a national news service no later than 9:00 a.m. New York City time, on the next business day after the Expiration Date for the Offer.

2.     Extension of Tender Period; Termination; Amendment.

        Under the Merger Agreement, we are required to extend the Expiration Date if, at the scheduled Expiration Date, any of the Tender Offer Conditions have not been satisfied or waived.

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Pursuant to the Merger Agreement, each such extension will not exceed the number of days that we reasonably believe is necessary to cause the Tender Offer Conditions to be satisfied and will not, in any event, exceed 30 Business Days unless the parties to the Merger Agreement (with action by the Company requiring the approval of the Special Committee) otherwise agree. In addition, we further reserve the right to extend the Offer for a period of time not to exceed ten Business Days (i) on one occasion, in order to obtain the tender of a majority of the Public Shares (the "Requisite Tender Amount"), provided that, at the time of extension, at least 40% of the Public Shares have been tendered and not withdrawn, and (ii) on one occasion, in order to obtain 90% of the total outstanding Shares, provided that, at the time of extension, the number of Public Shares that have been tendered and not withdrawn is sufficient, together with other Shares owned by us, or to be acquired under the Santo Agreement, to constitute at least 80% of the total outstanding Shares. "Business Day" means any day that is not a Saturday, a Sunday or other day on which Banks are required or authorized by Law to be closed in The City of New York.

        We also have the right to extend the Offer for any period required by any applicable law.

        If we extend the Expiration Date, during such extension, all Shares previously tendered and not withdrawn will remain subject to the Offer and subject to your right to withdraw your Shares. Company stockholders may withdraw their Shares previously tendered at any time prior to the Expiration Date as it may be extended from time to time. See Section 5—"Withdrawal Rights."

        We expressly reserve the right to waive (to the extent legally permissible) any of the Tender Offer Conditions. We may not, without the prior written consent of the Company by action of the Special Committee, decrease the Offer Price or change the form of consideration, decrease the number of Public Shares sought to be purchased in the Offer, impose additional conditions to the Offer or amend any other term of the Offer in any manner adverse to the holders of Public Shares, except as may be provided in the Merger Agreement.

        Subject to the Merger Agreement, if we make a material change in the terms of the Offer or if we waive a material condition to the Offer, we will extend the Offer and disseminate additional tender offer materials to the extent required by applicable law and the applicable regulations of the Securities and Exchange Commission (the "SEC"). The minimum period during which a tender offer must remain open following material changes in the terms of the Offer, other than a change in price or a change in the percentage of securities sought, depends upon the facts and circumstances, including the materiality of the changes. In the SEC's view, a tender offer should remain open for a minimum of five business days from the date the material change is first published, sent or given to stockholders, and, if material changes are made with respect to information that approaches the significance of price or the percentage of securities sought, a minimum of ten business days may be required to allow for adequate dissemination and investor response. With respect to a change in price, a minimum ten-business-day period from the date of the change is generally required to allow for adequate dissemination to stockholders. Accordingly, if, prior to the Expiration Date with the consent of the Special Committee, we decrease the number of Public Shares being sought, or increase or decrease the consideration offered pursuant to the Offer, and if the Offer is scheduled to expire at any time earlier than the period ending on the tenth business day from the date that notice of the increase or decrease is first published, sent or given to the Company stockholders, we will extend the Offer at least until the expiration of that period of ten business days. Under Exchange Act Rule 14d-1(g)(3), "business day" means any day other than Saturday, Sunday or a federal holiday and consists of the time period from 12:01 a.m. through 12:00 Midnight, New York City time.

        Any extension, delay, termination, waiver or amendment of the Offer will be followed as promptly as practicable by public announcement, in the case of an extension of the Offer to be made no later than 9:00 a.m., New York City time, on the next business day (as such term is

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defined under Exchange Act Rule 14d-1(g)(3)) after the previously scheduled Expiration Date, in accordance with the public announcement requirements of Exchange Act Rule 14e-1(d). Subject to applicable law (including Exchange Act Rules 14d-4(d) and 14d-6(c), which require that material changes in the information published, sent or given to any stockholders in connection with the Offer be promptly disseminated to stockholders in a manner reasonably designed to inform them of such changes), and without limiting the manner in which we may choose to make any public announcement, we have no obligation to publish, advertise or otherwise communicate any public announcements other than by issuing a press release through PR Newswire.

        If we extend the time during which the Offer is open, or if we delay the acceptance for payment of or payment for Shares pursuant to the Offer for any reason, then, without prejudice to our rights under the Offer, the Depositary may retain tendered Shares on our behalf and those Shares may not be withdrawn except to the extent tendering stockholders are entitled to withdrawal rights as described herein under Section 5—"Withdrawal Rights." However, our ability to delay the payment for Shares that we have accepted for payment is limited by Exchange Act Rule 14e-1(c), which requires that a bidder pay the consideration offered or return the securities deposited by or on behalf of stockholders promptly after the termination or withdrawal of the bidder's offer.

        The Merger Agreement will terminate automatically if the Santo Agreement is terminated and, at the time of such termination, none of the Santo Shares have been purchased by Novartis US or its affiliates, in which case the Offer, if then outstanding, will be abandoned. The Santo Agreement may be terminated by Santo or Novartis US on or after December 31, 2005 if the closing of the Santo Purchase has not occurred before that date. The Santo Agreement may also be terminated by the mutual written consent of Santo and Novartis US. See Subsection 12(b)—"The Merger Agreement—Termination" and Subsection 12(c)—"The Santo Agreement—Termination."

        At any time prior to the consummation of the Merger, the Merger Agreement may be terminated by the mutual written consent of the Company (by action of the Special Committee) and Novartis US, in which case the Offer and the Merger may be abandoned. Furthermore, if, following the completion of the Offer and the acceptance for payment or payment for any Public Shares tendered pursuant to the Offer, Novartis US or its Affiliates have not purchased the Requisite Tender Amount, the Merger Agreement will terminate. However, in such event, subject to applicable law, Novartis US will still have the right to thereafter designate each member of the Company Board. See Subsection 12(b)—"The Merger Agreement—Termination." Should the Offer be terminated pursuant to any of the foregoing provisions, all tendered Shares that have not been previously accepted for payment will be returned promptly to the tendering stockholders. See Subsection 12(b)—"The Merger Agreement—Termination."

3.     Acceptance for Payment and Payment.

        Upon the terms and subject to the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any such extension or amendment), we will accept for payment and pay for any and all Shares that are validly tendered on or prior to the Expiration Date and not properly withdrawn pursuant to the Offer as soon as we are permitted to do so under applicable law, subject to the satisfaction or waiver of the conditions set forth in Section 15—"Conditions to the Offer." For a description of our right to terminate the Offer and not accept for payment or pay for Shares or to delay acceptance for payment or payment for Shares, see Section 2—"Extension of Tender Period; Termination; Amendment."

If, prior to the Expiration Date, we increase the Offer Price, we will pay the increased Offer Price to all Company stockholders from whom we purchase Shares in the Offer, whether or not such Shares were tendered before the increase in price. As of the date of this Offer to Purchase, we have no intention to increase the Offer Price.

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        For purposes of the Offer, we will be deemed to have accepted for payment tendered Shares when, as and if we give oral or written notice of our acceptance to the Depositary. We will pay for Shares accepted for payment pursuant to the Offer by depositing the purchase price with the Depositary. The Depositary will act as your agent for the purpose of receiving payments from us and transmitting such payments to you. In all cases, payment for Shares accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of certificates for such Shares (or of a confirmation of a book-entry transfer of such Shares into the Depositary's account at the Book-Entry Transfer Facility (as defined in Section 4—"Procedure for Tendering Shares")) and a properly completed and duly executed Letter of Transmittal and any other required documents. Accordingly, payment may be made to tendering stockholders at different times if delivery of the Shares and other required documents occurs at different times. For a description of the procedure for tendering Shares pursuant to the Offer, see Section 4—"Procedure for Tendering Shares."

UNDER NO CIRCUMSTANCES WILL WE PAY INTEREST ON THE OFFER PRICE PAID FOR SHARES PURSUANT TO THE OFFER, REGARDLESS OF ANY DELAY IN MAKING SUCH PAYMENT. IF WE INCREASE THE OFFER PRICE, WE WILL PAY SUCH INCREASED OFFER PRICE FOR ALL SHARES PURCHASED PURSUANT TO THE OFFER.

        We reserve the right to transfer or assign, in whole or, from time to time, in part, to one or more of our affiliates the right to purchase Shares tendered pursuant to the Offer, in which case references to Purchaser in this Offer to Purchase will be references to the assignee or transferee, as the case may be, but any such transfer or assignment will not relieve us of our obligations under the Offer or prejudice your rights to receive payment for Shares validly tendered and accepted for payment.

        If any tendered Shares are not purchased pursuant to the Offer for any reason, or if certificates are submitted for more Shares than are tendered, certificates for such unpurchased or untendered Shares will be returned (or, in the case of Shares tendered by book-entry transfer, such Shares will be credited to an account maintained at the Book-Entry Transfer Facility, as defined below), without expense to you, as promptly as practicable following the expiration or termination of the Offer.

4.     Procedure for Tendering Shares.

        Valid Tender of Shares.    To tender Shares pursuant to the Offer, either (1) the Depositary must receive at one of its addresses set forth on the back cover of this Offer to Purchase (A) a properly completed and duly executed Letter of Transmittal and any other documents required by the Letter of Transmittal and (B) the share certificate(s) evidencing the Shares to be tendered (the "Share Certificates") or delivery of such Shares pursuant to the procedures for book-entry transfer described below (and a confirmation of such delivery, including an Agent's Message (as defined below) if the tendering stockholder has not delivered a Letter of Transmittal), in each case by the Expiration Date, or (2) the guaranteed delivery procedure described below must be complied with.

        The method of delivery of Share Certificates and all other required documents, including delivery through the Book-Entry Transfer Facility (as defined below), is at the option and risk of the tendering stockholder, and the delivery will be deemed made only when actually received by the Depositary including, in the case of a book-entry transfer, by Agent's Message. If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

        Book-Entry Delivery.    The Depositary will establish an account with respect to the Shares at The Depository Trust Company (the "Book-Entry Transfer Facility") for purposes of the Offer within two business days after the date of this Offer to Purchase, and any financial institution that is a participant in the system of the Book-Entry Transfer Facility may make delivery of Shares by causing the Book-Entry Transfer Facility to transfer such Shares into the Depositary's account in

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accordance with the procedures of the Book-Entry Transfer Facility. However, although delivery of Shares may be effected through book-entry transfer, the Letter of Transmittal properly completed and duly executed together with any required signature guarantees or an Agent's Message and any other required documents must, in any case, be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase by the Expiration Date, or the guaranteed delivery procedure described below must be complied with. "Agent's Message" means a message transmitted by the Book-Entry Transfer Facility to, and received by, the Depositary and forming a part of a Book-Entry Confirmation, which message states that the Book-Entry Transfer Facility has received an express acknowledgment from the participant in the Book-Entry Transfer Facility tendering the Shares that are the subject of the Book-Entry Confirmation that the participant has received and agrees to be bound by the terms of this Letter of Transmittal and that Purchaser may enforce that agreement against the participant.

        DELIVERY OF THE LETTER OF TRANSMITTAL AND ANY OTHER REQUIRED DOCUMENTS TO THE BOOK-ENTRY TRANSFER FACILITY DOES NOT CONSTITUTE DELIVERY TO THE DEPOSITARY.

        Signature Guarantees.    Except as otherwise provided below, all signatures on a Letter of Transmittal must be guaranteed by a financial institution (including most banks, savings and loan associations and brokerage houses) that is a member of a recognized Medallion Program approved by The Securities Transfer Association, Inc. (each, an "Eligible Institution"). Signatures on a Letter of Transmittal need not be guaranteed (1) if the Letter of Transmittal is signed by the registered holder of the Shares tendered therewith and such holder has not completed either the box entitled "Special Payment Instructions" or the box entitled "Special Delivery Instructions" on the Letter of Transmittal or (2) if such Shares are tendered for the account of an Eligible Institution. See Instructions 1–5 of the Letter of Transmittal.

        If the Share Certificates are registered in the name of a person other than the signer of the Letter of Transmittal, or if payment is to be made to, or Share Certificates for unpurchased Shares are to be issued or returned to, a person other than the registered holder, then the tendered Share Certificates must be endorsed or accompanied by appropriate stock powers, signed exactly as the name or names of the registered holder or holders appear on the Share Certificates, with the signatures on the Share Certificates or stock powers guaranteed by an Eligible Institution as provided in the Letter of Transmittal. See Instructions 1-5 of the Letter of Transmittal.

        If the Share Certificates are forwarded separately to the Depositary, a properly completed and duly executed Letter of Transmittal (or facsimile) must accompany each delivery of Share Certificates.

        Guaranteed Delivery.    If you wish to tender Shares pursuant to the Offer and cannot deliver such Share Certificates and all other required documents to the Depositary by the Expiration Date, or cannot complete the procedure for delivery by book-entry transfer on a timely basis, you may nevertheless tender such Shares if all of the following conditions are met:

(a)

such tender is made by or through an Eligible Institution;



(b)

a properly completed and duly executed Notice of Guaranteed Delivery in the form provided by Purchaser is received by the Depositary (as provided below) by the Expiration Date; and



(c)

the Share Certificates (or a confirmation of a book-entry transfer into the Depositary's account at the Book-Entry Transfer Facility), together with a properly completed and duly executed Letter of Transmittal (or facsimile thereof) with any required signature guarantee or an Agent's Message and any other documents required by the Letter of Transmittal, are

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received by the Depositary within three Nasdaq National Market trading days after the date of execution of the Notice of Guaranteed Delivery.

        The Notice of Guaranteed Delivery may be delivered by hand or transmitted by facsimile transmission or mailed to the Depositary and must include a guarantee by an Eligible Institution in the form set forth in such Notice. The method of delivery of Shares and all other required documents, including through the Book-Entry Transfer Facility, is at your option and risk, and the delivery will be deemed made only when actually received by the Depositary. If certificates for Shares are sent by mail, we recommend registered mail with return receipt requested, properly insured.

        Backup Withholding.    Under U.S. federal income tax law, the Depositary may be required to withhold a portion of any payments made to certain stockholders pursuant to the Offer or the Merger. In order to avoid such backup withholding, you must provide the Depositary with your correct taxpayer identification number ("TIN") and certify that you are not subject to such backup withholding by completing the Substitute Form W-9 included in the Letter of Transmittal. Certain stockholders (including, among others, all corporations and certain foreign individuals and entities) are not subject to backup withholding. If a stockholder does not provide its correct TIN or fails to provide the certifications described above, the Internal Revenue Service may impose a penalty on the stockholder, and payment of cash to the stockholder pursuant to the Offer or the Merger may be subject to backup withholding. All stockholders tendering Shares pursuant to the Offer should complete and sign the Substitute Form W-9 included in the Letter of Transmittal to provide the information necessary to avoid backup withholding. If you are a non-resident alien or foreign entity not subject to backup withholding, you must give the Depositary a properly completed Form W-8 BEN (or successor form) in order to avoid backup withholding with respect to payments made to you.

        Grant of Proxy.    By executing a Letter of Transmittal (or delivering an Agent's Message), you irrevocably appoint designees of Purchaser as your proxies in the manner set forth in the Letter of Transmittal to the full extent of your rights with respect to the Shares tendered and accepted for payment by us (and any and all other Shares or other securities issued or issuable in respect of such Shares on or after the date of this Offer to Purchase). All such proxies are irrevocable and coupled with an interest in the tendered Shares. Such appointment is effective only upon our acceptance for payment of such Shares. Upon such acceptance for payment, all prior proxies and consents granted by you with respect to such Shares and other securities will, without further action, be revoked, and no subsequent proxies may be given nor subsequent written consents executed (and, if previously given or executed, will cease to be effective). Our designees will be empowered to exercise all your voting and other rights as they, in their sole discretion, may deem proper at any annual, special or adjourned meeting of the Company's stockholders by written consent or otherwise. We reserve the right to require that, in order for Shares to be validly tendered, immediately upon our acceptance for payment of such Shares, we are able to exercise full voting rights with respect to such Shares and other securities (including voting at any meeting of stockholders then scheduled or acting by written consent without a meeting). The foregoing proxies are effective only upon acceptance for payment of Shares pursuant to the Offer.

        This Offer does not constitute a solicitation of proxies, absent a purchase of Shares, for any meeting of the Company's stockholders. Any solicitation of proxies which Purchaser or Novartis US might make will be made only pursuant to separate proxy solicitation materials complying with the requirements of Section 14(a) of the Exchange Act.

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        The tender of Shares pursuant to any one of the procedures described above will constitute your acceptance of the Offer, as well as your representation and warranty that (1) you own the Shares being tendered and (2) you have the full power and authority to tender, sell, assign and transfer the Shares tendered free and clear of all liens, restrictions, charges and encumbrances and not subject to any adverse claims, as specified in the Letter of Transmittal. Our acceptance for payment of Shares tendered by you pursuant to the Offer will constitute a binding agreement between us with respect to such Shares, upon the terms and subject to the conditions of the Offer. Persons tendering Shares will, upon request, be required to execute and deliver any additional documents deemed to be necessary or desirable to complete the sale, assignment and transfer of the Shares tendered and to verify the accuracy of any representations and warranties made.

        Validity.    We will determine, in our sole discretion, all questions as to the form of documents and the validity, eligibility (including time of receipt) and acceptance for payment of any tender of Shares, and our determination will be final and binding. We reserve the absolute right to reject any or all tenders of Shares that we determine not to be in proper form or the acceptance for payment of or payment for which may, in the opinion of our counsel, be unlawful. We also reserve the absolute right to waive any defect or irregularity in any tender of Shares of any particular stockholder, whether or not similar defects or irregularities are waived in the case of other stockholders. Our interpretation of the terms and conditions of the Offer will be final and binding. None of Novartis AG, Novartis US, Purchaser, the Dealer Manager, the Depositary, the Information Agent or any other person will be under any duty to give notification of any defect or irregularity in tenders or waiver of any such defect or irregularity or incur any liability for failure to give any such notification.

5.     Withdrawal Rights.

        Other than during a subsequent offering period, if one is provided, you may withdraw tenders of Shares made pursuant to the Offer at any time prior to the Expiration Date. Thereafter, such tenders are irrevocable, except that they may be withdrawn after July 21, 2005, unless such Shares have been accepted for payment as provided in this Offer to Purchase.

        If we extend the period of time during which the Offer is open, are delayed in accepting for payment or paying for Shares pursuant to the Offer for any reason or are unable to accept Shares for payment pursuant to the Offer for any reason, then, without prejudice to our rights under the Offer, the Depositary may, on our behalf, retain all Shares tendered, and such Shares may not be withdrawn except as otherwise provided in this Section.

        To withdraw tendered Shares, a written or facsimile transmission notice of withdrawal with respect to the Shares must be timely received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase, and the notice of withdrawal must specify the name of the person who tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the registered holder of the Shares, if different from that of the person who tendered such Shares. If the Shares to be withdrawn have been delivered to the Depositary, a signed notice of withdrawal with (except in the case of Shares tendered by an Eligible Institution) signatures guaranteed by an Eligible Institution must be submitted prior to the release of such Shares. In addition, such notice must specify, in the case of Shares tendered by delivery of certificates, the name of the registered holder (if different from that of the tendering stockholder) and the serial numbers shown on the particular certificates evidencing the Shares to be withdrawn or, in the case of Shares tendered by book-entry transfer, the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Shares. Withdrawals may not be rescinded, and Shares withdrawn will thereafter be deemed not validly tendered for purposes of the Offer. However, withdrawn Shares may be re-tendered by again following one of the procedures described in Section 4—"Procedure for Tendering Shares," at any time prior to the Expiration Date.

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        We will determine, in our sole discretion, all questions as to the form and validity (including time of receipt) of any notice of withdrawal, and our determination will be final and binding. None of Novartis AG, Novartis US, Purchaser, the Depositary, the Dealer Manager, the Information Agent or any other person will be under any duty to give notification of any defect or irregularity in any notice of withdrawal or waiver of any such defect or irregularity or incur any liability for failure to give any such notification.

        If Purchaser provides a subsequent offering period following the Offer, no withdrawal rights will apply to Shares tendered during that subsequent offering period or to Shares tendered in the Offer and accepted for payment.

6.     Certain U.S. Federal Income Tax Consequences.

        The following is a general summary of certain U.S. federal income tax consequences of the Offer and the Merger to stockholders of the Company whose Shares are tendered and accepted for payment pursuant to the Offer, or whose Shares are converted into cash in the Merger. The summary is based on the Internal Revenue Code of 1986, as amended (the "Code"), applicable Treasury Regulations, and administrative and judicial interpretations thereof, each as in effect as of the date of this Offer to Purchase, all of which may change, possibly with retroactive effect. The summary is for general information only and does not purport to address all of the tax consequences that may be relevant to particular stockholders in light of their personal circumstances. The summary applies only to stockholders who hold their Shares as capital assets and may not apply to stockholders subject to special rules under the Code, including, without limitation, persons who acquired their Shares upon the exercise of stock options or otherwise as compensation, financial institutions, brokers, dealers or traders in securities or commodities, insurance companies, partnerships or other entities treated as partnerships or flow-through entities for U.S. federal income tax purposes, tax-exempt organizations, persons who are subject to alternative minimum tax, persons who hold Shares as a position in a "straddle" or as part of a "hedging" or "conversion" transaction or other integrated investment, or persons that have a functional currency other than the United States dollar. This summary does not discuss the U.S. federal income tax consequences to any stockholder of the Company who, for U.S. federal income tax purposes, is a non-resident alien individual, foreign corporation, foreign partnership or foreign estate or trust, and does not address any state, local or foreign tax consequences of the Offer or the Merger.

        BECAUSE INDIVIDUAL CIRCUMSTANCES MAY DIFFER, EACH STOCKHOLDER SHOULD CONSULT SUCH STOCKHOLDER'S TAX ADVISOR REGARDING THE APPLICABILITY OF THE RULES DISCUSSED BELOW TO SUCH STOCKHOLDER AND THE PARTICULAR TAX EFFECTS TO SUCH STOCKHOLDER OF THE OFFER AND THE MERGER, INCLUDING THE APPLICATION AND EFFECT OF STATE, LOCAL AND FOREIGN TAX LAWS OR ANY U.S. FEDERAL TAX LAWS OTHER THAN THE U.S. FEDERAL INCOME TAX LAWS.

        The receipt of cash in exchange for Shares pursuant to the Offer or the Merger will be a taxable transaction for U.S. federal income tax purposes. In general, a stockholder who sells Shares pursuant to the Offer or receives cash in exchange for Shares pursuant to the Merger will recognize gain or loss for U.S. federal income tax purposes equal to the difference, if any, between the amount of cash received and the holder's adjusted tax basis in the Shares sold pursuant to the Offer or exchanged for cash pursuant to the Merger. Gain or loss will be determined separately for each block of Shares (i.e., Shares acquired at the same cost in a single transaction) sold pursuant to the Offer or exchanged for cash pursuant to the Merger. Any such gain or loss generally will be long-term capital gain or loss if the stockholder has held the Shares for more than one year. Certain limitations apply to the use of capital losses.

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7.     Price Range of Company Common Stock; Dividends.

        The Shares are listed on the Nasdaq National Market under the symbol "ELAB." The following table shows the high and low closing sales prices of the Shares for all periods during the last two years. Share prices are as reported on the Nasdaq National Market based on published financial sources. The nominal closing sales prices listed below for fiscal year 2003 are adjusted to reflect a 2-for-1 stock split that occurred on June 2, 2004. According to the Company's Quarterly Report filed with the SEC on Form 10-Q for the quarterly period ended March 31, 2005, as of May 5, 2005, 88,884,564 Shares were outstanding.

		High		Low
FY 2003
	First Quarter	$	13.49	$	9.98
	Second Quarter		18.59		13.37
	Third Quarter		20.88		15.09
	Fourth Quarter		27.39		19.07
FY 2004
	First Quarter	$	33.54	$	22.37
	Second Quarter		44.46		32.40
	Third Quarter		40.08		21.70
	Fourth Quarter		27.83		21.73
FY 2005
	First Quarter	$	30.57	$	24.53

        On February 4, 2005, the last trading day prior to media speculation about a possible takeover of the Company, the reported closing price on the Nasdaq National Market for the Shares was $24.75. Therefore, the Offer Price represents approximately a 25% premium to the reported closing price of the Shares on the last trading day prior to media speculation about a possible takeover of the Company. On February 18, 2005, the last full day of trading prior to the announcement of the execution of the Merger Agreement, the reported closing price on the Nasdaq National Market for the Shares was $27.92. On May 20, 2005, the last full day of trading prior to the date of this Offer to Purchase, the reported closing price on the Nasdaq National Market for the Shares was $30.15.

PRIOR TO DETERMINING WHETHER TO TENDER YOUR SHARES, WE URGE YOU TO OBTAIN CURRENT MARKET QUOTATIONS FOR THE SHARES.

8.     Effect of the Offer on the Market for the Company Common Stock; Registration Under the Exchange Act; Margin Regulations.

        The purchase of Shares by Purchaser pursuant to the Offer will reduce the number of Shares that might otherwise trade publicly and will reduce the number of holders of Shares, which could adversely affect the liquidity and market value of the remaining Shares held by the public. The extent of the public market for the Shares and the availability of quotations depends upon the number of stockholders holding the Shares, the aggregate market value of the Shares remaining at such time, the interest of maintaining a market in the Shares on the part of any securities firms, and other factors.

        Depending upon the number of Shares purchased pursuant to the Offer, the Shares that are not owned by Novartis AG, Novartis US, Purchaser or their subsidiaries may no longer meet the requirements for continued inclusion in the Nasdaq National Market, which require that an issuer have either (1) at least 750,000 publicly held shares with a market value of at least $5 million, held by at least 400 stockholders of round lots, and stockholders' equity of at least $10 million, or (2) at least 1,100,000 publicly held shares with a market value of at least $15 million, held by at least 400

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stockholders of round lots, and either (A) a market value of listed securities of at least $50 million or (B) total assets and total revenue of $50 million each for the most recently completed fiscal year or two of the last three most recently completed fiscal years. If these standards are not met, the Shares might nevertheless continue to be included in the Nasdaq Stock Market with quotations published in its Nasdaq Smallcap Market, but if the number of round lot holders of Shares were to fall below 300, or if the number of publicly held Shares were to fall below 500,000, or there were not at least two registered and active market makers for the Shares, the rules of The Nasdaq Stock Market, Inc. provide that the Shares would no longer be "qualified" for Nasdaq Stock Market reporting and the Nasdaq Stock Market would cease to provide any quotations. Shares held directly or indirectly by Company directors, Company officers, or beneficial owners of more than 10% of the Shares will not be considered as being publicly held for this purpose. If, as a result of the purchase of the Shares pursuant to the Offer or otherwise, the Shares no longer meet the requirements for continued inclusion in any tier of the Nasdaq Stock Market and the Shares are no longer included in any tier of the Nasdaq Stock Market, the market for Shares could be adversely affected.

        In the event that the Shares no longer meet the requirements for continued inclusion in any tier of the Nasdaq Stock Market, it is possible that the Shares would continue to trade in the over-the-counter market and that price quotations would be reported by other sources. The extent of the public market for the Shares and the availability of such quotations would, however, depend upon the number of holders of Shares remaining at such time, the interest in maintaining a market in Shares on the part of securities firms, the possible termination of registration of the Shares under the Exchange Act, as described below, and other factors. There can be no assurance that there will be an active market for the Shares following the completion of the Offer. If the Merger does not occur and there is not an active market for the Shares, the value of the remaining Shares may be negatively affected.

        The Shares are currently registered under the Exchange Act. Such registration may be terminated upon application by the Company to the SEC if the Shares are not listed on a "national securities exchange" and there are fewer than 300 record holders. This would substantially reduce the information required to be furnished by the Company to holders of Shares and to the SEC and would make certain provisions of the Exchange Act, such as the short-swing profit recovery provisions of Section 16(b), the requirement of furnishing a proxy statement in connection with stockholders' meetings and the requirements of Exchange Act Rule 13e-3 with respect to "going private" transactions, no longer applicable to the Shares. In addition, "affiliates" of the Company and persons holding "restricted securities" of the Company may be deprived of the ability to dispose of such securities pursuant to Rule 144 under the Securities Act of 1933, as amended. According to American Stock Transfer & Trust Company, the transfer agent for the Company, as of May 16, 2005, there were 23 record holders of Shares.

        Pursuant to the Merger Agreement, following the completion of the Offer, Novartis US and Purchaser are required to use their reasonable best efforts to keep the Shares quoted for trading on the Nasdaq National Market as long as the Company is required to be registered under the Exchange Act and satisfies the Nasdaq National Market's listing standards (other than standards entirely within the Company's control).

        The Shares are currently "margin securities" under the regulations of the Board of Governors of the Federal Reserve System, which regulations have the effect, among other things, of allowing brokers to extend credit on the collateral of the Shares for the purpose of buying, carrying or trading in securities ("Purpose Loans"). Depending upon factors, such as the number of record holders of the Shares and the number and market value of publicly held Shares, following the purchase of Shares pursuant to the Offer, the Shares might no longer constitute "margin securities"

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for purposes of the Federal Reserve Board's margin regulations and, therefore, could no longer be used as collateral for Purpose Loans made by brokers.

9.     Certain Information Concerning the Company.

        General.    The Company is a Delaware corporation, with principal executive offices at 1999 Marcus Avenue, Lake Success, NY 11042. The telephone number for the Company's executive office is (516) 478-9700. The Company reported the following information in its Annual Report on Form 10-K for the fiscal year ended December 31, 2004, and the following description of the Company and its business is qualified in its entirety by reference to such reports.

        The Company is a generic pharmaceutical company engaged in developing, licensing, manufacturing, selling and distributing a broad range of prescription pharmaceutical products primarily in the United States. The Company focuses primarily on drugs in a broad range of solid oral dosage forms, utilizing both immediate and sustained release delivery, in tablet, multiple layer tablet, film-coated tablet and capsule forms. The Company does not depend on any single drug or therapeutic category for a majority of its sales. For the year ended December 31, 2004, the Company generated sales and operating income of approximately $431.0 million and $172.6 million, respectively, and had total assets of approximately $545.2 million.

        OTHER AVAILABLE INFORMATION.    THE COMPANY IS SUBJECT TO THE INFORMATIONAL REQUIREMENTS OF THE EXCHANGE ACT AND IN ACCORDANCE THEREWITH FILES PERIODIC REPORTS, PROXY STATEMENTS AND OTHER INFORMATION WITH THE SEC RELATING TO ITS BUSINESS, FINANCIAL CONDITION AND OTHER MATTERS. THE COMPANY IS REQUIRED TO DISCLOSE IN SUCH PROXY STATEMENTS CERTAIN INFORMATION, AS OF PARTICULAR DATES, CONCERNING THE COMPANY'S DIRECTORS AND OFFICERS, THEIR REMUNERATION, STOCK OPTIONS GRANTED TO THEM, THE PRINCIPAL HOLDERS OF THE COMPANY'S SECURITIES AND ANY MATERIAL INTEREST OF SUCH PERSONS IN TRANSACTIONS WITH THE COMPANY. SUCH REPORTS, PROXY STATEMENTS AND OTHER INFORMATION MAY BE INSPECTED AND COPIED AT THE PUBLIC REFERENCE FACILITIES MAINTAINED BY THE SEC AT JUDICIARY PLAZA, 450 FIFTH STREET, N.W., WASHINGTON, D.C. 20549. PLEASE CALL THE SEC AT 1-800-SEC-0330 FOR FURTHER INFORMATION ON THE PUBLIC REFERENCE FACILITIES. COPIES OF SUCH MATERIAL CAN ALSO BE OBTAINED AT THE WEB SITE MAINTAINED BY THE SEC AT HTTP://WWW.SEC.GOV.

        EXCEPT AS OTHERWISE STATED IN THIS OFFER TO PURCHASE, THE INFORMATION CONCERNING THE COMPANY CONTAINED HEREIN HAS BEEN TAKEN FROM OR IS BASED UPON REPORTS AND OTHER DOCUMENTS ON FILE WITH THE SEC OR OTHERWISE PUBLICLY AVAILABLE. WE TAKE NO RESPONSIBILITY FOR THE ACCURACY OR COMPLETENESS OF THE INFORMATION CONTAINED IN ANY SUCH REPORTS AND OTHER DOCUMENTS OR FOR ANY FAILURE BY THE COMPANY TO DISCLOSE EVENTS THAT MAY HAVE OCCURRED AND MAY AFFECT THE SIGNIFICANCE OR ACCURACY OF ANY SUCH INFORMATION CONTAINED IN SUCH REPORTS AND OTHER DOCUMENTS BUT THAT ARE UNKNOWN TO US.

10.  Certain Information Concerning Novartis AG, Novartis US and Purchaser.

        General.    Purchaser is a Delaware corporation incorporated on February 16, 2005 with principal executive offices at 608 Fifth Avenue, New York, NY 10020 and is an indirect wholly owned subsidiary of Novartis US. The telephone number of Purchaser's principal executive offices is (212) 307-1122. Purchaser was formed solely for the purposes of engaging in the Offer and the Merger. To date, Purchaser has engaged in no activities other than those incident to its formation and the commencement of the Offer.

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        Novartis US is a New York corporation with principal executive offices at 608 Fifth Avenue, New York, NY 10020 and is an indirect wholly owned subsidiary of Novartis AG. The telephone number of Novartis US's executive offices is (212) 307-1122. Novartis AG's group of companies is a world leader in the discovery, development, manufacture and marketing of prescription medications, and Novartis US indirectly owns most of the companies of the Novartis AG group operating in the U.S.

        Except as set forth elsewhere in this Offer to Purchase: (a) none of Novartis AG, Novartis US, or Purchaser or, to the knowledge of Novartis AG, Novartis US, or Purchaser, any of the persons listed in Schedule I to this Offer to Purchase or any associate or majority owned subsidiary of Novartis AG, Novartis US, or Purchaser or of any of the persons so listed, beneficially owns or has a right to acquire any Shares or any other equity securities of the Company, (b) neither Novartis AG, Novartis US, or Purchaser nor, to the knowledge of Novartis AG, Novartis US, or Purchaser, any of the persons or entities referred to in clause (a) above or any of their executive officers, directors or subsidiaries has effected any transaction in the Shares or any other equity securities of the Company during the past 60 days, (c) neither Novartis AG, Novartis US, or Purchaser nor, to the knowledge of Novartis AG, Novartis US, or Purchaser, any of the persons listed in Schedule I to this Offer to Purchase, has any contract, arrangement, understanding or relationship with any other person with respect to any securities of the Company (including, but not limited to, any contract, arrangement, understanding or relationship concerning the transfer or the voting of any such securities, joint ventures, loan or option arrangements, puts or calls, guaranties of loans, guaranties against loss, or the giving or withholding of proxies, consents or authorizations), (d) in the past two years, there have been no transactions that would require reporting under the rules and regulations of the SEC between Novartis AG, Novartis US, or Purchaser or any of their respective subsidiaries, or, to the knowledge of Novartis AG, Novartis US, or Purchaser, any of the persons listed in Schedule I to this Offer to Purchase, on the one hand, and the Company or any of its executive officers, directors or affiliates, on the other hand, and (e) in the past two years, there have been no contacts, negotiations or transactions between Novartis AG, Novartis US, or Purchaser or any of their respective subsidiaries, or, to the knowledge of Novartis AG, Novartis US, or Purchaser, any of the persons listed in Schedule I to this Offer to Purchase, on the one hand, and the Company or any of its subsidiaries or affiliates, on the other hand, concerning a merger, consolidation or acquisition, a tender offer or other acquisition of securities, an election of directors or a sale or other transfer of a material amount of assets.

        None of the persons listed in Schedule I to this Offer to Purchase has, during the past five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). None of the persons listed in Schedule I to this Offer to Purchase has, during the past five years, been a party to any judicial or administrative proceeding (except for matters that were dismissed without sanction or settlement) that resulted in a judgment, decree or final order enjoining the person from future violations of, or prohibiting activities subject to, United States federal or state securities laws, or a finding of any violation of United States federal or state securities laws.

        Certain Litigation With the Company.    In August 2000, Novartis Pharmaceuticals Corporation, Novartis AG, Novartis Pharma AG, and Novartis International Pharmaceutical Ltd. filed a complaint in the United States District Court for the District of Delaware alleging, among other things, that the Company's generic cyclosporine product infringes a patent owned by the Novartis entities. In December 2002, the United States District Court for the District of Delaware granted the Company's motion for summary judgment of non-infringement of the patent. In April 2004, the United States Court of Appeals for the Federal Circuit affirmed the judgment of the Delaware district court that the Company's generic cyclosporine product does not infringe the portent patent. The Novartis entities' request for a rehearing by the United States Appeals Court is pending.

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        Available Information.    Novartis AG is a foreign private issuer as defined in Exchange Act Rule 3b-4 and is subject to the Exchange Act reporting requirements applicable to foreign private issuers. In accordance therewith, it files periodic reports and other information with the SEC relating to its business, financial condition and other matters. Such reports and other information should be available for inspection and copying at the offices of the SEC in the same manner as set forth with respect to the Company in Section 9—"Certain Information Concerning the Company."

11.  Background of the Offer; Past Contacts or Negotiations with the Company.

        As part of its ongoing business development activities, Novartis AG's group of companies (collectively, "Novartis") continually reviews opportunities for business combinations. In this connection, Novartis identified Hexal, a privately-held German generics company, as a company that could be of strategic benefit to Novartis' generics franchise.

        In June 2003, Novartis International AG ("Novartis International") approached Hexal to discuss the possibility of a sale. Also in June 2003, Novartis International began working with Goldman, Sachs & Co. ("Goldman Sachs") to assist Novartis International in considering a transaction with Hexal.

        Exploratory meetings took place between representatives of Novartis and Hexal in February and April 2004. In April, Hexal informed Novartis that its management would make a presentation and provide an information package on the business in June 2004. The presentation was subsequently delayed until September 2004.

        On September 30, 2004, discussions commenced regarding a possible acquisition of Hexal by Novartis. As part of the contemplated acquisition of Hexal by Novartis, Dr. Thomas Strüngmann and Dr. Andreas Strüngmann, on behalf of the Strüngmann family, the owners of Hexal, who also indirectly own the Santo Shares through Santo, expressed their interest in selling the Santo Shares as well.

        On November 8, 2004, Dr. Raymund Breu, the Chief Financial Officer of Novartis AG, had a telephone conversation with Dr. Bernhard Hampl, the Chief Executive Officer of the Company, to arrange an introductory meeting between various representatives of Novartis and Dr. Hampl. During this meeting, which took place on November 16, 2004, Dr. Hampl delivered a company presentation and answered questions related to the business.

        As a follow up meeting to the November 16 meeting, on December 17, 2004, representatives of Novartis and Dr. Hampl discussed the Company's research and development strategy and product pipeline during a conference call.

        At a meeting on January 19, 2005, Novartis AG's board of directors reviewed the potential acquisition of the Company. In light of the advancing progress of the Hexal discussions and the interest of the Strüngmann family in selling the Santo Shares, Novartis AG's board of directors decided to pursue a joint acquisition of Hexal and the Company.

        From January 26, 2005 to January 28, 2005, representatives of Novartis and its advisors held discussions with representatives of Hexal and the Strüngmann family and their advisors regarding a nonbinding Memorandum of Understanding (the "MoU") for a potential acquisition of Hexal and the Company. The MoU described certain terms of a proposed acquisition of Hexal by Novartis International, including a purchase price of €4,500,000,000 (including €165 million net debt) with economic effect as of January 1, 2005. The MoU also described certain terms of a proposed acquisition of the Company, subject to the approval of the Company Board, including the independent directors on the Company Board. The MoU described that Novartis International or one or more of its affiliates would acquire or have an option to acquire the Santo Shares for a purchase price of €1,300,000,000, regardless of whether the public shareholders of the Company

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received a higher price per Public Share. The MoU described certain additional conditions to the proposed transactions, including completion of due diligence and definitive documentation. The MoU also included provisions regarding confidentiality, business integration and noncompetition by Dr. Thomas Strüngmann and Dr. Andreas Strüngmann. On January 30, 2005, Novartis International and Dr. Thomas Strüngmann and Dr. Andreas Strüngmann entered into the MoU and the parties agreed to negotiate exclusively with each other with respect to the potential transactions.

        On January 31, 2005, Dr. Breu contacted Dr. Hampl and Mark Patterson, an independent member of the Company Board, to inform them of Novartis' intention to acquire the Santo Shares and its desire to also acquire the Public Shares. Novartis indicated that it desired to perform a due diligence investigation of the Company. Dr. Hampl suggested that the parties enter into a confidentiality agreement and requested that Novartis International provide a first draft of the agreement.

        On February 2, 2005, Novartis sent a draft Confidentiality Agreement to the Chief Financial Officer of the Company. Also on that day, the Special Committee retained Simpson, Thacher & Bartlett LLP as its legal counsel.

        On February 3, 2005, Mr. Patterson informed Novartis that the Company Board had constituted the Special Committee, consisting of Mr. Patterson and Douglas Karp, another independent director, to consider the proposed transaction.

        On February 4, 2005, upon the request of the Special Committee, Novartis submitted to the Special Committee a preliminary non-binding indication of interest at $25 to $28 per Share. Also on that day, the Special Committee retained Merrill Lynch & Co. ("Merrill Lynch") as its financial advisor.

        On February 7–8, 2005, representatives of Novartis carried out site visits of the Company's two production facilities in Wilson, NC and Laurelton, NY.

        On or around February 9, 2005, Novartis International engaged Wachtell, Lipton, Rosen & Katz as special counsel to assist it in considering a transaction with the Company.

        The Confidentiality Agreement was negotiated over the period from February 3 to 11, 2005, by Novartis International, Novartis US, the Company, the Special Committee and their respective advisers. At the request of the Special Committee, the Confidentiality Agreement included a standstill provision restricting the ability of Novartis US and its affiliates to acquire Public Shares (subject to certain exceptions) for a one-year period and a provision that committed Novartis US, if it or its affiliates acquired the Santo Shares, to make a tender offer for any and all of the Public Shares at a price per Share equal to the dollar equivalent value of the amount of Euro paid for the Santo Shares (calculated as of the date of the agreement to acquire the Santo Shares), and, if a majority of the Public Shares were tendered in that tender offer, to effect a merger to acquire the remaining Public Shares at the same price. At the request of the Special Committee, Novartis US confirmed that it had no intention of reducing the amount that it would pay for the Santo Shares in return for an increase in other consideration to be paid to the owners of the Santo Shares and, were Novartis US to do so, the tender offer price for the Public Shares would not be reduced.

        On February 10, 2005, Thomas Strüngmann called Dr. Breu and indicated that, based on discussions he had with the Special Committee, he believed that the Special Committee would approve a transaction at a price of $32.50 for the Public Shares. Dr. Strüngmann indicated to Dr. Breu that he hoped that Novartis would be able to secure the approval of the Special Committee and, if Novartis were willing to increase the price it was willing to offer for the Public Shares, the Strüngmann family might consider contributing a portion of the additional purchase price to the holders of the Public Shares.

        The parties signed the Confidentiality Agreement on February 11, 2005. Later on February 11, 2005, representatives of Novartis commenced a due diligence investigation of the Company, including meeting with Company executives.

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        On February 13, 2005, Novartis proposed a draft Merger Agreement to the Company and the Special Committee. Over the period between February 13-17, representatives of Novartis, the Company, the Special Committee and their respective advisors negotiated and agreed upon most of the key terms of the Merger Agreement other than the price to be offered for the Public Shares. At the request of the Special Committee, the draft merger agreement provided that Novartis US would, in connection with acquiring the controlling block of Santo Shares, offer the public shareholders of the Company an opportunity to participate in the sale of control by means of a tender offer for any and all Public Shares at the price to be agreed between Novartis US and the Special Committee. Novartis US also agreed in principle with the Special Committee's request that, if a majority of the Public Shares were tendered into the tender offer, Novartis US would effect a merger to acquire the remaining shares at the offer price, and that if less than a majority of the Public Shares were tendered into the tender offer, it would refrain from effecting a merger until February 11, 2006 (other than a short-form merger at the same offer price if it subsequently owned 90% or more of the outstanding shares of the Company), but would only acquire additional Public Shares through voluntary transactions prior to that date. The draft merger agreement also provided that the Company Board and the Special Committee would recommend the transaction to the Company's public shareholders and approve the transactions (including approval of the acquisition of the Santo Shares, the tender offer and the Merger for purposes of Section 203 of the DCGL, although Novartis US indicated that it did not believe that such approval would be required for the Merger following its purchase of the Santo Shares).

        On February 15, 2005, Goldman Sachs, on behalf of Novartis, communicated to Merrill Lynch an indicative offer of $28.50 per Public Share. On behalf of the Special Committee, Merrill Lynch rejected this indicative offer and did not provide a counterproposal.

        On February 16, 2005, Goldman Sachs, on behalf of Novartis, communicated to Merrill Lynch a revised proposal of $29.00 per Public Share. Again, after discussions with the Special Committee, Merrill Lynch rejected this proposal without providing a counterproposal.

        Over the period between February 7-17, Novartis International and Hexal and their respective advisors, negotiated the terms of an agreement for the purchase of Hexal. Following its due diligence investigation of Hexal, Novartis reduced the price to be paid for Hexal to €4,350,000,000 due to a reduction in Hexal's expected profits for 2004 (subject to adjustment for certain events), but in exchange for the Hexal price reduction, the parties agreed that the purchase price would bear interest from and after January 1, 2005 through the closing under the Hexal Agreement at an annualized rate of 1% above the three-months Euro Interbank Offering Rate (EURIBOR). On February 16-17, Novartis (Deutschland) GmbH ("Novartis Deutschland"), an affiliate of Novartis AG, entered into the Hexal Agreement with members of the Strüngmann family. While the Hexal Agreement was finalized and notarized on February 17, 2005, it was not ratified. Pursuant to German law, the Hexal Agreement was subject to ratification by each of the parties thereto before becoming binding on the parties.

        During the period between February 12-18, Novartis and Santo and their respective advisors negotiated the Santo Agreement for the purchase of the Santo Shares for a price of €1,300,000,000 plus interest from January 1, 2005 through the closing of the Santo Purchase at an annualized rate of 1% above the three-months EURIBOR (which was equivalent to $28.45 per Santo Share as of the date on which the Santo Agreement was signed based upon accrued interest through such date at the interest rate provided for in the Santo Agreement and the Euro-dollar exchange rate, both as of the close of business on February 18, 2005 (the last business day prior to the date on which the Santo Agreement was signed)). On February 15, Dr. Thomas Strüngmann indicated to Novartis that any consideration to the holders of the Public Shares above the price being received for the Santo Shares would be at Novartis' cost. During the February 12-18 negotiation period, Novartis and Santo agreed that Novartis US's obligation to purchase the Santo Shares would be conditioned upon the prior or contemporaneous closing of the purchase under the Hexal Agreement and upon

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the contemporaneous closing of a tender offer for the Public Shares but that the seller's obligations under the Santo Agreement would not be conditioned upon the closing of such transactions. Novartis US and Santo did not enter into the Santo Agreement pending developments in the discussions between Novartis and the Special Committee.

        On February 17, 2005, Dr. Breu had a telephone conversation with Mr. Patterson, in which Dr. Breu reiterated the proposal by Novartis to pay $29.00 per Public Share and Mr. Patterson indicated that the Special Committee would be willing to consider a transaction at a price of $32.25 per Public Share.

        On February 18, 2005, Dr. Breu had several telephone conversations with Mr. Patterson to discuss a price at which the Special Committee would be willing to approve a transaction and recommend the transaction to the holders of the Public Shares. Dr. Breu communicated that Novartis was willing to increase its offer for the Public Shares to $29.50 per Public Share, but Mr. Patterson indicated that $29.50 was too low. The Special Committee indicated that it would consider a price of $31.75 per Public Share.

        On February 19, 2005, Dr. Daniel Vasella, the Chairman of Novartis AG, met with Mr. Patterson and indicated that Novartis would be willing to offer $31.00 per Public Share as its best and final offer on the basis that the transaction be promptly approved by the Special Committee and that the Special Committee recommend that the holders of Public Shares tender their Shares. Mr. Patterson said he would be willing to recommend that the Special Committee accept that price and would advise Novartis after the meeting of the Special Committee.

        On February 20, 2005, the advisers of the Special Committee advised Novartis and its advisors as follows: the Special Committee and the Company Board met with their respective legal and financial advisers on February 19, 2005 to consider Novartis' proposal; at that meeting, Merrill Lynch delivered to the Special Committee its oral opinion (which opinion was delivered in writing on February 20, 2005) that, as of that date and based on the factors set forth in the opinion, the consideration being offered for the Public Shares was fair to the holders of those shares from a financial point of view; also at that meeting, the Special Committee and the Company Board approved Novartis US's purchase of the Santo Shares, including for purposes of Section 203 of the DGCL, approved the Merger Agreement pursuant to which Novartis US would make a tender offer for the Public Shares at a price of $31.00 per Share and would effect a merger at the same price if a majority of the Public Shares were tendered into the offer, and resolved to recommend that holders of the Public Shares tender such shares to Novartis US and adopt the Merger Agreement.

        Later on February 20, 2005, Santo, Novartis US and Novartis AG entered into the Santo Agreement, the parties to the Hexal Agreement ratified the Hexal Agreement, and Novartis AG, Novartis US, Purchaser and the Company entered into the Merger Agreement.

12.  Purpose of the Offer; the Merger Agreement; the Santo Agreement; Statutory Requirements; Appraisal Rights; "Going Private" Transactions; Plans for the Company

        YOU SHOULD NOT RELY UPON THE REPRESENTATIONS AND WARRANTIES IN THE MERGER AGREEMENT OR THE SANTO AGREEMENT OR THE DESCRIPTION OF THEM IN THIS OFFER TO PURCHASE AS STATEMENTS OF FACTUAL INFORMATION ABOUT NOVARTIS AG, NOVARTIS US, PURCHASER, SANTO, THE COMPANY OR ANY OTHER PERSON OR ENTITY. THESE REPRESENTATIONS AND WARRANTIES WERE MADE BY THE RESPECTIVE PARTIES ONLY FOR PURPOSES OF THE MERGER AGREEMENT AND THE SANTO AGREEMENT, WERE MADE SOLELY TO THE RESPECTIVE PARTIES IN EACH SUCH AGREEMENT AS OF THE DATE OF EACH SUCH AGREEMENT AND ARE SUBJECT TO MODIFICATION OR QUALIFICATION BY OTHER DISCLOSURES MADE IN CONNECTION THEREWITH. THE REPRESENTATIONS AND WARRANTIES ARE REPRODUCED AND SUMMARIZED IN THIS OFFER TO PURCHASE SOLELY TO PROVIDE INFORMATION REGARDING THE TERMS OF THE MERGER AGREEMENT AND THE SANTO AGREEMENT AND NOT FOR ANY OTHER PURPOSE.

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        (a)   Purpose.    The purpose of the Offer and the Merger is to acquire the entire equity interest in the Company. The Offer is intended to facilitate the acquisition of all of the Shares not purchased pursuant to the Santo Agreement or acquired indirectly pursuant to the Hexal Agreement. The purpose of the Merger is to acquire all of the Shares not purchased pursuant to the Santo Agreement or the Offer, indirectly acquired pursuant to the Hexal Agreement, or otherwise.

        (b)   The Merger Agreement.    The following summary description of the Merger Agreement is qualified in its entirety by reference to the full text of the Merger Agreement, which is filed as an exhibit to the Tender Offer Statement on Schedule TO that Novartis US and Purchaser have filed with the SEC, which you may examine and copy as set forth in Section 9—"Certain Information Concerning the Company."

        The Offer.    The Merger Agreement provides that Purchaser will commence the Offer and that, upon the terms and subject to prior satisfaction or waiver of the conditions of the Offer, as set forth in Section 15—"Conditions of the Offer," Purchaser will purchase any and all Shares validly tendered and not withdrawn pursuant to the Offer. The Merger Agreement provides that, without the prior written consent of the Company by action of the Special Committee, Purchaser will not decrease the price to be paid in the Offer or change the form of consideration payable in the Offer, decrease the number of Public Shares sought to be purchased in the Offer, impose conditions to the Offer in addition to those set forth in Section 1.1 of the Merger Agreement or amend any other term of the Offer in a manner adverse to the holders of Public Shares.

        Under the Merger Agreement, Novartis US and Purchaser are required to extend the Expiration Date if at the scheduled Expiration Date any of the Tender Offer Conditions have not been satisfied or waived. Pursuant to the Merger Agreement, each such extension will not exceed the number of days that Novartis US and Purchaser reasonably believe is necessary to cause the Tender Offer Conditions to be satisfied and will not, in any event, exceed 30 Business Days unless the parties to the Merger Agreement (with action by the Company requiring the approval of the Special Committee) otherwise agree. Novartis US and Purchaser further reserve the right to extend the Offer for a period of time not to exceed ten Business Days (i) on one occasion in order to obtain the tender of a majority of the Public Shares (which is sometimes referred to herein as the "Requisite Tender Amount"), provided that at the time of extension at least 40% of the Public Shares have been tendered and not withdrawn, and (ii) on one occasion in order to obtain 90% of the total outstanding Shares, provided that at the time of extension the number of Public Shares that have been tendered and not withdrawn is sufficient, together with other Shares owned by Novartis US and Purchaser, or to be acquired under the Santo Agreement, to constitute at least 80% of the total outstanding Shares.

        Novartis US and Purchaser also have the right to extend the Offer for any period required by applicable law. In addition, Purchaser and Novartis US may provide one subsequent offering period of between three and 20 business days.

        Recommendation.    The Company represented and warranted to Novartis US and Purchaser in the Merger Agreement that both the Company Board and the Special Committee, at a meeting duly called at which a quorum was present throughout, (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the DGCL, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders, and (iv) took all other action within the Company Board's and the Special Committee's power to render Section 203 of the DGCL, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger. The Company further represented and warranted that Merrill Lynch delivered to the Special Committee its written opinion dated February 20, 2005, subject to the qualifications therein set forth, to the effect that, as of the date of the Merger

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Agreement, the consideration to be received by the holders of Public Shares pursuant to the Offer and the Merger is fair, from a financial point of view, to such stockholders. See Annex II to the Company's Schedule 14D-9.

        Directors.    The Merger Agreement provides that, subject to compliance with applicable law, Novartis US, promptly upon the date on which Purchaser becomes obligated to accept any Public Shares for payment pursuant to the Offer (the "Acceptance Date"), and from time to time thereafter, will be entitled to designate each member of the Company Board, and the Company will take all actions necessary to cause Novartis US's designees to be elected, including, if necessary, seeking the resignations of one or more existing directors and prior to the Acceptance Date removing any potential restriction on the ability of any Novartis US designees to serve on the Company Board. However, if Novartis US and Purchaser have obtained a majority of the Public Shares, then until the Merger becomes effective (see "—The Merger" below), Novartis US and Purchaser will allow the members of the Special Committee or their designees to remain on the Company Board, provided that if both of the members of the Special Committee are unwilling or unable to remain on the Company Board and neither has designated a replacement, Novartis US will be permitted to replace such members with other independent directors, who will thereafter be deemed the "Special Committee" (although such independent directors shall not have the authority to decrease the consideration to be paid in connection with the Merger).

        The Merger.    If a majority of the Public Shares are tendered in the Offer, under the Merger Agreement, Novartis US is obligated to and will cause a merger of Purchaser and the Company in which all outstanding Shares that are not purchased in the Offer (other than Shares owned by the Company or by Novartis AG or any of its subsidiaries) will be cancelled and automatically converted into the right to receive the Offer Price in cash, without interest. The Merger Agreement provides that, at the Effective Time (as defined below), Purchaser will be merged with and into the Company. Following the Merger, the separate corporate existence of Purchaser will cease and the Company will continue as the surviving corporation (the "Surviving Corporation") and an indirect wholly owned subsidiary of Novartis US. The Merger will become effective when the Certificate of Merger has been filed with the Delaware Secretary of State or at such later time as will be agreed upon by Novartis US and the Company and specified in the Certificate of Merger (the "Effective Time").

        Charter, By-Laws, Directors and Officers.    At the Effective Time, the certificate of incorporation of Purchaser, as in effect immediately prior to the Effective Time, will be amended in its entirety to read the same as the certificate of incorporation of the Surviving Corporation until amended as provided therein or by the DGCL and the by-laws of Purchaser, as in effect immediately prior to the Effective Time, will be amended in its entirety to read the same as the by-laws of the Surviving Corporation until amended as provided therein, in the Surviving Corporation's certificate of incorporation or in accordance with the DGCL. The indemnification and exculpation provisions of the certificate of incorporation and by-laws of the Company as in effect on February 20, 2005 will be included in the certificate of incorporation and by-laws of the Surviving Corporation and may not be amended, repealed or otherwise modified for a period of six years from the Acceptance Date in any manner that would adversely affect the rights under those provisions of all present and former directors, officers or employees of the Company. From and after the Effective Time, the officers of the Company will be the officers of the Surviving Corporation and the directors of the Purchaser will be the directors of the Surviving Corporation, in each case, until their respective successors are duly elected and qualified.

        Company Stockholder Meeting.    In the event that a majority of the Public Shares are tendered in the Offer, the Merger Agreement requires that the Company, in accordance with applicable law and if required by applicable law in order to consummate the Merger, will (a) duly call, give notice of, convene and hold a special meeting of the Company stockholders (the "Special Meeting") as

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soon as practicable following the Acceptance Date for the purpose of considering and taking action upon the Merger Agreement; (b) prepare and file with the SEC a preliminary proxy statement or information statement relating to the Merger Agreement and any other required filings, and use its reasonable efforts (1) to obtain and furnish the information required to be included by the SEC in the Proxy Statement (as defined below) and, after consultation with Novartis US, to respond promptly to any comments made by the SEC with respect to the preliminary proxy statement and cause a definitive proxy or information statement and any other required documents to be mailed to the Company stockholders (the "Proxy Statement") and (2) to obtain the necessary approvals for the Merger, the Merger Agreement and the transactions contemplated by the Merger Agreement by the Company stockholders; and (c) subject to the terms of the Merger Agreement (including the right of the Special Committee to modify or withdraw its recommendation under certain circumstances), include, if required, in the Proxy Statement the recommendation of the Company Board and the Special Committee that the stockholders of the Company adopt the Merger Agreement.

        Novartis US has agreed in the Merger Agreement that it will vote, or cause to be voted, all of the Shares then owned by it, Purchaser or any of Novartis US's other affiliates or with respect to which it or any of its affiliates has the power to vote or cause to be voted, in favor of the approval of the Merger Agreement.

        The Merger Agreement further provides that, notwithstanding the foregoing, if Novartis US, Purchaser or any other of Novartis US's subsidiaries acquires at least 90% of the total outstanding Shares following the purchase of the Santo Shares and the completion of the Offer, the parties to the Merger Agreement will take all necessary and appropriate action to cause the Merger to become effective as soon as practicable after the payment by Purchaser for Shares pursuant to the Offer without a meeting of the Company stockholders in accordance with Section 253 of the DGCL. Appraisal rights will be available to Company stockholders who do not tender their Shares in the Offer and subsequently do not vote in favor of the Merger (if a stockholder vote is required to approve the Merger), if such Company stockholders comply with applicable procedures under Delaware law. See Subsection 12(e)—"Appraisal Rights."

        Conversion of Securities.    By virtue of the Merger and without any further action on the part of the Company stockholders, at the Effective Time, each Share issued and outstanding immediately prior to the Effective Time (other than (a) any Shares owned by the Company directly as treasury stock or by Novartis AG or any of its subsidiaries (other than in a representative or fiduciary capacity), and (b) Shares held by a holder that is entitled to demand and properly demands appraisal for those Shares ("Dissenting Shares") in accordance with the provisions of Section 262 of the DGCL ("Section 262"), which Appraisal Shares will only be entitled to the rights granted under Section 262), will be canceled and cease to exist, and will be converted into and represent the right to receive the Merger Consideration. If a Company stockholder fails to validly perfect or loses the right to appraisal under Section 262 or if a court of competent jurisdiction determines that the Company stockholder is not entitled to the relief provided by Section 262, then the rights of the Company stockholder under Section 262 will cease, and the Appraisal Shares will be deemed to have been converted at the Effective Time into, and will have become, the right to receive the Merger Consideration without interest as provided above. See Subsection 12(e)—"Appraisal Rights."

        Treatment of Stock Options.    The Merger Agreement provides that, as of the Effective Time, each unexpired and unexercised outstanding option granted or issued under any employee stock option or compensation plan or arrangement of the Company (each, a "Company Option") will automatically be cancelled, and the holder of a Company Option will receive as soon as reasonably practicable following the Effective Time a cash payment equal to the product of (a) the excess, if any, of the Merger Consideration over the exercise price per share of such Company Option and (b) the number of Shares issuable upon exercise of such Company Option.

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        Representations and Warranties.    Pursuant to the Merger Agreement, Novartis US and Purchaser have made customary representations and warranties to the Company with respect to, among other matters, Novartis US and Purchaser's organization and standing, corporate power and authority, conflicts, consents and approvals, required funds, and ownership of Company stock. The Company has made customary representations and warranties to Novartis US and Purchaser with respect to, among other matters, its organization and standing, its subsidiaries, corporate power and authority, capitalization, conflicts, Company reports and financial statements, undisclosed liabilities, absences of certain changes, litigation, actions under state takeover laws, brokers' and finders' fees, and the opinion of the Special Committee Financial Advisor.

        HSR Act Filings; Reasonable Efforts; Notification.    The Merger Agreement obligates (a) each of Novartis US and the Company to make or cause to be made the filings required under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended ("HSR Act"), and any other applicable antitrust laws, to comply with information requests of any governmental authority and to cooperate with the other party in connection with any such filings, and (b) each of Novartis US and the Company to use their reasonable best efforts to take, or cause to be taken, all actions, and to do or cause to be done, all things necessary, proper or advisable to consummate and make effective the Offer, the Merger and the transactions contemplated by the Merger Agreement.

        Public Announcements.    The Merger Agreement provides that, unless required by applicable law or listing agreements with or rules of any national securities exchange or national market system on which such party's securities are listed or traded, the Company and Novartis US will consult with the other before issuing any press release or otherwise making any public statement with respect to the Offer, the Merger and the transactions contemplated by the Merger Agreement.

        Indemnification; Directors' and Officers' Insurance.    Pursuant to the Merger Agreement, for a period of six years from the Acceptance Date, the indemnification and exculpation provisions of the certificate of incorporation and by-laws of the Surviving Corporation may not be amended, repealed or otherwise modified in any manner that would adversely affect the rights of all present and former directors, officers or employees of the Company. In the Merger Agreement, the Surviving Corporation has also agreed to maintain in effect, for a period of six years after the Effective Time, policies of directors' and officers' liability insurance covering each person who was covered under such policies as of the date of the Merger Agreement on terms with respect to coverage and amount no less favorable than those in effect on the date of the Merger Agreement, subject to certain limitations.

        Conduct of the Company's Operations.    In the Merger Agreement, the Company further agreed, as to itself and its subsidiaries, except as expressly contemplated or permitted by the Merger Agreement that:

•

the Company will conduct its business only in the ordinary and usual course, consistent with past practice, and it and its subsidiaries will use their respective commercially reasonable efforts to (i) preserve their current business organizations intact and maintain their existing relations and goodwill with material customers, suppliers, distributors, creditors, lessors, licensors, licensees, agents, employees, business associates and others having material business dealings with them to the end that the Company's and its subsidiaries' goodwill and ongoing businesses will not be impaired in any material respect at the Effective Time; (ii) maintain and keep their properties and assets in good repair and condition; and (iii) maintain in effect all governmental permits pursuant to which the Company or any of its subsidiaries currently operates;



•

neither the Company nor any of its subsidiaries will (i) amend or modify its certificate of incorporation or by-laws or similar organizational documents ("Organizational Documents") in any way that would or would be reasonably expected to adversely affect the consummation of the transactions contemplated by the Merger Agreement, including the Offer and the

34

Merger, including the timing therefor; (ii) split, combine or reclassify its outstanding shares of capital stock; (iii) declare, set aside or pay any dividend payable in cash, stock or property in respect of any capital stock (other than dividends from its direct or indirect wholly owned subsidiaries to it or a wholly owned subsidiary in the ordinary course of business); (iv) repurchase, redeem or otherwise acquire any shares of its capital stock or any securities convertible into or exchangeable or exercisable for any shares of its capital stock or permit any of its subsidiaries to purchase or otherwise acquire any shares of its capital stock or any securities convertible into or exchangeable or exercisable for any shares of its capital stock; or (v) make any other change in its capital structure;

•

except as provided for in the Merger Agreement or as required under agreements already in existence, there will not be any material increase in the compensation payable or that could become payable by the Company or any of its subsidiaries to directors, officers or key employees or any material amendment of any of the Company's employee compensation and employee benefit plans other than increases to employees that are not officers made in the ordinary course of business consistent with past practice;



•

neither the Company nor any subsidiary will (i) directly or indirectly, sell, transfer, lease, pledge, mortgage, encumber or otherwise dispose of any material portion of its property or assets (including stock or other ownership interests of its subsidiaries) or (ii) acquire a material amount of assets or capital stock of any other Person, other than in the ordinary course of business, consistent with past practice;



•

neither the Company nor any of its subsidiaries will make any change in accounting principles, practices or methods which is not required by U.S. generally accepted accounting principles;



•

neither the Company nor any of its subsidiaries will issue, sell, pledge, dispose of or encumber any shares of, or securities convertible into or exchangeable or exercisable for, or options, warrants, calls, commitments or rights of any kind to acquire, any shares of its capital stock of any class or any other property or assets, other than Shares issuable pursuant to options or restricted share units (whether or not vested) outstanding on the date hereof;



•

neither the Company nor any of its subsidiaries will extend, modify, terminate, amend or enter into any contract with any affiliate of the Company, except pursuant to intercompany transactions in the ordinary course of business, consistent with past practice;



•

neither the Company nor any of its subsidiaries will incur any indebtedness for borrowed money that cannot be repaid or retired within 30 days at no penalty; and



•

neither the Company nor any of its subsidiaries will authorize or enter into an agreement to do anything prohibited by any of the above covenants.

        No Solicitation.    During the term of the Merger Agreement, the Company will not, and will not authorize or permit any of its subsidiaries or any of its or their officers, directors, employees, counsel, accountants and other authorized representatives to, directly or indirectly, solicit, initiate or encourage any inquiries or the making of any proposal with respect to any merger, liquidation, recapitalization, consolidation or other business combination involving the Company or its subsidiaries or acquisition of any capital stock or any material portion of the assets of the Company or its subsidiaries, or any combination of the foregoing (other than Novartis US, Purchaser or their respective directors, officers, employees, agents and representatives); provided, however, that at any time prior to the Acceptance Date the Company may furnish information, hold discussions and take related actions in respect of any such proposal received that was not solicited or knowingly encouraged by the Company if, but only if, after consultation with its outside counsel, the Special Committee determines that doing so is required in the proper exercise of its fiduciary duties.

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        Access to Information.    The Merger Agreement provides, except as otherwise prohibited by applicable law, that the Company will give Novartis US's representatives reasonable access during normal business hours to the Company's properties, books, contracts and records and will furnish to Novartis US all information concerning its business, properties, and personnel as Novartis US reasonably requests.

        Anti-Takeover Statutes.    The Merger agreement also provides that if any anti-takeover statute is or may become applicable to the purchase of the Santo Shares, the Merger or the other transactions contemplated by the Merger Agreement, each of Novartis US, the Company and Purchaser and their respective Board of Directors (or with respect to Company, the Special Committee, if appropriate) will grant all such approvals and take all such actions as are necessary so that such transactions may be consummated as promptly as practicable on the terms contemplated by the Merger Agreement and otherwise act to eliminate or minimize the effects of such statute or regulation on such transactions.

        Section 16 Matters.    The Merger Agreement also provides that prior to the Acceptance Date, the Company Board will take all steps as may be required and permitted to cause the transactions contemplated by the Merger Agreement, including any dispositions of Shares (including derivative securities with respect to such Shares) by each individual who is or will be subject to the reporting requirements of Section 16(a) of the Exchange Act with respect to the Company to be exempt under Rule 16b-3 promulgated under the Exchange Act.

        Nasdaq Listing.    The Merger Agreement provides that Novartis US and Purchaser will use their reasonable best efforts, following the Acceptance Date and until the earlier of (i) the Effective Time and (ii) February 11, 2006, to keep the Shares quoted for trading on the Nasdaq National Market as long as the Company is required to be registered under the Exchange Act and satisfies the Nasdaq National Market listing standards (other than standards entirely within the Company's control).

        Conditions to Consummation of the Merger.    Pursuant to the Merger Agreement, the respective obligations of Novartis US, Purchaser and the Company to consummate the Merger are subject to the satisfaction or, to the extent permitted by applicable law, waiver at or prior to the Effective Time, of each of the following conditions:

•

The completion of the Offer on the terms and subject to the conditions set forth in the Merger Agreement and the Requisite Tender Amount having been purchased in the Offer. This condition is waivable only with the approval of the Special Committee.



•

No court or governmental entity of competent jurisdiction having enacted, issued, promulgated, enforced or entered any statute, law, ordinance, rule, regulation, judgment, decree, injunction or other order that is in effect or taken any other action enjoining, restraining or otherwise prohibiting the consummation of the Merger or has the effect of making the purchase of Shares illegal.

        Change in Form of Transaction.    Notwithstanding the condition to the Merger that the Requisite Tender Amount have tendered in the Offer, if the Offer can not be completed on the terms and subject to the conditions set forth in the Merger Agreement as a result of the failure to satisfy a requirement of law in connection with the Offer, but the Merger is capable of consummation in compliance with the requirements of law, then the parties to the Merger Agreement will, subject to all applicable legal requirements, proceed with the consummation of the Merger, subject in such circumstances to the additional condition that the Merger be approved at the Special Meeting by a majority of the remaining Public Shares. If the Merger is not approved by a majority of the remaining Public Shares at such Special Meeting, the Merger Agreement will automatically terminate and such date of the Special Meeting will be deemed to be the Acceptance Date. On the Acceptance Date, the standstill provisions of the Confidentiality Agreement will be amended to provide that Novartis US and Purchaser will be permitted to make acquisitions of Shares that are voluntary to the holders of Shares (such as by means of legally permissible open market purchases or additional tender offers) and may consummate a merger or other business combination with the Company prior to February 11, 2006 only if certain conditions are satisfied. See "—Revised Standstill."

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        Termination.    The Merger Agreement will terminate automatically if the Santo Agreement is terminated and, at the time of such termination, none of the Santo Shares have been purchased by Novartis US or its affiliates, in which case the Offer, if then outstanding, will be abandoned. The Santo Agreement may be terminated by Santo or Novartis US on or after December 31, 2005 if the closing of the Santo Purchase has not occurred before that date. The Santo Agreement may also be terminated by the mutual written consent of Santo and Novartis US. See Subsection 12(c)—"The Santo Agreement—Termination."

        At any time prior to the consummation of the Merger, the Merger Agreement may be terminated by the mutual written consent of the Company (by action of the Special Committee) and Novartis US, in which case the Offer and the Merger may be abandoned. Further, if, following the completion of the Offer and the acceptance for payment or payment for any Public Shares tendered pursuant to the Offer, Novartis US or its affiliates have not purchased the Requisite Tender Amount, the Merger Agreement will terminate. However, in such event, subject to applicable law, Novartis US will still have the right to thereafter designate each member of the Company Board.

        Should the Offer be terminated pursuant to any of the foregoing provisions, all tendered Shares that have not been previously accepted for payment will be returned promptly to the tendering stockholders.

        Revised Standstill.    In the event that less than a majority of the Public Shares are tendered in the Offer, the Merger Agreement provides that the standstill provisions of the Confidentiality Agreement will be amended to provide that, although under the Confidentiality Agreement, Novartis US and its affiliates may not acquire additional Public Shares by means of a merger until February 11, 2006, Novartis US and its subsidiaries will be permitted to make acquisitions of Shares that are voluntary to the holders of Shares (such as by means of legally permissible open market purchases or additional tender offers) and may consummate a merger or other business combination with the Company prior to February 11, 2006, only if: (1) a majority of the then-outstanding Public Shares approve such transaction; or (2) Novartis US and its subsidiaries at such time own 90% or more the total outstanding Shares, provided that the price per Share paid in any such transaction described in (2) above is at least equal to the Offer Price.

        Amendment.    The Merger Agreement may be modified or amended by the Company, Novartis US and Purchaser at any time prior to the Effective Time by written agreement, provided that any modifications or amendments of provisions that are for the benefit of the Company may only be effected with the approval of the Special Committee.

        Expenses.    All costs and expenses incurred in connection with the Offer and the Merger and the transactions contemplated by the Merger Agreement will be paid by the party to the Merger Agreement incurring such expenses, except that each of the Company and Novartis US will pay one-half of the costs and expenses incurred in connection with filing, printing and mailing the Proxy Statement.

        (c)   The Santo Agreement.    The following summary description of the Santo Agreement is qualified in its entirety by reference to the Santo Agreement, which is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC, which the Company stockholders may examine and copy as set forth in Section 9—"Certain Information Concerning the Company."

        Pursuant to the Santo Agreement, Santo has agreed to sell, and Novartis US has agreed to acquire, the Santo Shares for €1,300,000,000, plus interest from January 1, 2005 through the date (the "Santo Closing Date") of the closing of the Santo Purchase (the "Santo Closing") at an annualized rate of 1% above the three-month Euro Interbank Offering Rate (EURIBOR). The €1,300,000,000 price plus accrued interest through February 20, 2005, represented approximately

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$28.45 per Share based on the dollar-to-euro exchange rate and the interest rate provided for in the Santo Agreement, both as of the close of business on February 18, 2005 (the last business day prior to the date on which the Santo Agreement was signed). Based on the exchange rate and interest rate, both as of the close of business on May 20, 2005, (the last business day prior to the date of this Offer to Purchase), and including interest through May 22, 2005 (the day prior to the date of this Offer to Purchase), Novartis US is paying approximately $27.54 per Santo Share. The Santo Closing will occur within ten business days following the date on which all of the closing conditions set forth in the Santo Agreement, except the closing deliveries, have been satisfied or waived. Based on the dollar-to-euro exchange rate and the interest rate provided for in the Santo Agreement, both as of the close of business on February 18, 2005 (the last business day prior to the date on which the Santo Agreement was signed), the price paid per Santo Share would not equal the Offer Price until approximately January 2008, at the earliest.

        Conduct of the Company's Business.    Among other things, the Santo Agreement obligates Santo to use its best efforts to cause the Company to operate diligently in the ordinary course of business, consistent with past practice, and to cause the Company to fulfill its covenants and obligations under the Merger Agreement. Santo specifically covenants and agrees to use best efforts to cause the Company not to:

•

modify or amend its organizational documents in any way that would or would be reasonably expected to adversely affect the consummation of the transactions contemplated by the Santo Agreement including the timing therefor;



•

incur any indebtedness for borrowed money that cannot be repaid or retired within 30 (thirty) days at no penalty;



•

(1) declare, set aside or pay any dividends on, or make any other distributions in respect of, any of its capital stock, other than dividends and distributions by any subsidiary of the Company to the Company; (2) split, combine or reclassify any of its capital stock, or issue or authorize the issuance of any other securities, including in respect of, in lieu of or in substitution for shares of its capital stock; (3) purchase, redeem or otherwise acquire any shares of its capital stock or any rights, warrants or options to acquire any such shares or other securities; or (4) take any action to transfer value from the Company to Santo or its other affiliates;



•

extend, modify, terminate, amend or enter into any contract with any affiliate of the Company, except pursuant to intercompany transactions in the ordinary course; or



•

authorize or commit to do or agree to take, whether in writing or otherwise, any of the foregoing actions.

        Pursuant to the Santo Agreement, Santo also agrees to cause Dr. Thomas Strüngmann to remain in his current position as an officer of the Company through the Santo Closing.

        Closing Conditions.    Pursuant to the Santo Agreement, the respective obligations of Novartis US and Santo to consummate the Santo Purchase are subject to the satisfaction of certain conditions.

        The obligations of Novartis US are subject to the satisfaction on or before the Santo Closing Date of each of the following conditions unless previously waived in writing by Novartis US:

•

The representations and warranties of Santo contained in the Santo Agreement that are qualified as to materiality or material adverse effect (or words of similar effect) being true and accurate at and as of the Santo Closing Date as if made as of such date, and the representations and warranties that are not qualified by materiality or material adverse effect

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(or words of similar effect) being true and accurate in all material respects as of the Santo Closing Date as if made as of such date;

•

Santo having performed and complied with, in all material respects, all obligations and covenants required by the Santo Agreement to be performed or complied with by Santo prior to or on the Santo Closing Date;



•

The closing of the transactions contemplated by the Hexal Agreement having been consummated or being consummated contemporaneously with the Santo Closing;



•

The representations and warranties of the Company contained in the Merger Agreement that are qualified as to materiality or material adverse effect (or words of similar effect) being true and accurate at and as of the Santo Closing Date as if made as of such date, and the representations and warranties that are not qualified by materiality or material adverse effect (or words of similar effect) being true and accurate in all material respects as of the Santo Closing Date as if made as of such date;



•

The Company having performed and complied with, in all material respects, all obligations and covenants required by the Merger Agreement to be performed or complied with by the Company prior to or on the Santo Closing Date;



•

All consents necessary to consummate the purchase and sale of the Santo Shares (including, without limitation, expiration of all applicable waiting periods under the HSR Act) having been received in form and substance reasonably satisfactory to Novartis US and no further consents or approval being required, and no impediments existing, to the consummation of the transactions contemplated by the Merger Agreement;



•

There being nothing preventing the consummation of the Offer from occurring contemporaneously with the Santo Closing;



•

No governmental entity of competent jurisdiction having enacted, issued, promulgated, enforced or entered any statute, rule, regulation, or non-appealable judgment, decree, injunction or other order that is in effect on the Santo Closing Date and prohibits the consummation of the Santo Closing; and



•

Novartis US having received the certificates representing the Santo Shares and all other documents required under the Santo Agreement to be submitted by Santo to Novartis US at the Closing.

        The obligations of Santo to consummate the transactions contemplated by the Santo Agreement are subject to the satisfaction on or before the Santo Closing Date of each of the following conditions unless previously waived in writing by Santo:

•

The representations and warranties of Novartis US and Novartis AG contained in the Santo Agreement being true and accurate as of the Santo Closing Date as if made as of such date;



•

Novartis US and Novartis AG having performed and complied with, in all material respects, all obligations and covenants required by the Santo Agreement to be performed or complied with by each of them prior to or on the Santo Closing Date;



•

No governmental entity of competent jurisdiction having enacted, issued, promulgated, enforced or entered any statute, rule, regulation, or non-appealable judgment, decree, injunction or other order that is in effect on the Santo Closing Date and prohibits the consummation of the Santo Closing; and



•

Santo having received the purchase price required to be paid by Novartis US.

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        Termination.    The Santo Agreement may be terminated and the transactions contemplated thereby may be abandoned at any time prior to the Santo Closing (a) by mutual written consent of Santo and Novartis US, or (b) by either Novartis US or Santo on or after December 31, 2005, provided that the terminating party is not in material breach of its obligations under the Santo Agreement or under the Hexal Agreement.

        (d)   Statutory Requirements.    Under the DGCL a merger of two Delaware corporations requires the adoption of a resolution by the board of directors of each of the corporations desiring to merge approving an agreement of merger containing provisions with respect to certain statutorily specified matters and the approval of the agreement of merger by the stockholders of each corporation by the affirmative vote of holders representing at least a majority of all the outstanding shares of stock entitled to vote on the merger, unless otherwise provided for in the corporation's certificate of incorporation or, in the case of a short-form merger, as described in the next paragraph. Accordingly, except in the case of a short-form merger, a vote of holders representing at least a majority of the outstanding Shares is required in order to adopt the Merger Agreement. The Shares entitle the Company stockholders to voting rights. If the Santo Closing occurs, Novartis US will have sufficient voting power to approve the Merger Agreement at a duly convened Company stockholders' meeting without the affirmative vote of any other Company stockholder. See Subsection 12(b)—"The Merger Agreement—Revised Standstill." If the Requisite Tender Amount is tendered in the Offer, under the Merger Agreement, Novartis US is obligated to and will cause a merger of Purchaser and the Company in which all outstanding Shares that are not purchased in the Offer (other than Shares owned by the Company directly as treasury stock or by Novartis AG or any of its subsidiaries (other than in a representative or fiduciary capacity and other than Shares held by Company stockholders that perfect their appraisal rights under the DGCL)) will be cancelled and automatically converted into the right to receive the Offer Price in cash, without interest.

        The DGCL also provides that, if a parent company owns at least 90% of each class of stock of a subsidiary, the parent company can effect a short-form merger with that subsidiary without the action of the other stockholders of the subsidiary. Accordingly, if, as a result of the Offer or otherwise, Novartis US, Purchaser or any other subsidiary of Novartis US acquires or controls the voting power of at least 90% of the outstanding Shares, the Merger will become effective without any action by any other Company stockholder.

        (e)   Appraisal Rights.    No appraisal rights are available in connection with the Offer. If the Merger is consummated, however, Company stockholders that have not tendered their Shares will have certain rights under the DGCL to dissent and demand appraisal of, and to receive payment in cash of the fair value of, their Shares. Company stockholders that perfect these rights by complying with the procedures set forth in Section 262 of the DGCL will have the fair value of their Shares (exclusive of any element of value arising from the accomplishment or expectation of the Merger) determined by the Delaware Court of Chancery and will be entitled to receive a cash payment equal to such fair value from the Surviving Corporation. In addition, such dissenting Company stockholders (the "Dissenting Stockholders") would be entitled to receive payment of a fair rate of interest from the date of consummation of the Merger on the amount determined to be the fair value of their Shares. In determining the fair value of the Dissenting Shares, the court is required to take into account all relevant factors. Accordingly, the determination could be based upon considerations other than, or in addition to, the market value of the Shares, including, among other things, asset values and earning capacity. In Weinberger v. UOP, Inc., the Delaware Supreme Court stated that "proof of value by any techniques or methods which are generally considered acceptable in the financial community and otherwise admissible in court" should be considered in an appraisal proceeding. The Weinberger court also noted that, under Section 262 of the DGCL, fair value is to be determined "exclusive of any element of value arising from the accomplishment or expectation of the merger." In Cede & Co. v. Technicolor, Inc., however, the Delaware Supreme

40

Court stated that, in the context of a two-step cash merger, "to the extent that value has been added following a change in majority control before cash-out, it is still value attributable to the going concern," to be included in the appraisal process. As a consequence, the fair value determined in any appraisal proceeding could be more or less than the consideration to be paid in the Offer and the Merger.

        Novartis US does not intend to object, assuming the proper procedures are followed, to the exercise of appraisal rights by any Dissenting Stockholder and the demand for appraisal of, and payment in cash for the fair value of, the Dissenting Shares. Novartis US intends, however, to cause the Surviving Corporation to argue in an appraisal proceeding that, for purposes of such proceeding, the fair value of each Dissenting Share is less than the price paid in the Merger. In this regard, the Company stockholders should be aware that the opinion of Merrill Lynch referred to in this Offer to Purchase is not necessarily an opinion as to fair value under Section 262 of the DGCL.

        The preservation and exercise of appraisal rights require strict adherence to the applicable provisions of the DGCL which will be provided to the Company stockholders who do not tender Shares into the Offer. Company stockholders who tender shares in the Offer will not have appraisal rights.

        (f)    "Going Private" Transactions.    The SEC has adopted Rule 13e-3 promulgated under the Exchange Act ("Rule 13e-3"), which is applicable to certain "going private" transactions and which may, under certain circumstances, be applicable to the Merger. However, Rule 13e-3 would be inapplicable if the Merger or other business combination is consummated within one year after the purchase of the Shares pursuant to the Offer and the amount paid per Share in the Merger or other business combination is at least equal to the amount paid per Share in the Offer. Novartis US and Purchaser believe that Rule 13e-3 will not be applicable to the Merger if the Merger will be effected within one year following the consummation of the Offer and, in the Merger, the Company stockholders will receive the same price per Share as paid in the Offer. If applicable, Rule 13e-3 requires, among other things, that certain financial information concerning the fairness of the proposed transaction and the consideration offered to minority stockholders in the transaction be filed with the SEC and disclosed to stockholders prior to the consummation of the transaction.

        (g)   Plans for the Company.    Upon the consummation of the Merger, the Company will become an indirect wholly owned subsidiary of Novartis US. In connection with the Offer, Novartis US and Purchaser have reviewed and will continue to review various possible business strategies that they might consider in the event that Purchaser acquires complete control of the Company, whether pursuant to the Offer, the Merger or otherwise. These changes could include, among other things, changes in the Company's business, corporate structure, capitalization and management.

        Each of the Company Board and the Special Committee has unanimously approved the Merger and the Merger Agreement. If at least a majority of the Public Shares are tendered into the Offer, the Company Board will be required to submit the Merger Agreement to the Company stockholders for their approval. If Company stockholder approval is required, the Merger Agreement must be approved by holders representing a majority of the outstanding Shares entitled to vote at a duly convened meeting of the Company's stockholders.

        If Novartis US (or its designee) purchases all of the Santo Shares, Novartis US and Purchaser will have sufficient voting power to approve the Merger Agreement at a duly convened meeting of the Company stockholders without the affirmative vote of any other Company stockholder. If the Requisite Tender Amount is purchased pursuant to the Offer, Purchaser and Novartis US will effect the Merger as promptly as practicable. Novartis US has agreed to vote, or cause to be voted, for the approval of the Merger any Shares owned by Purchaser, beneficially owned by it or any of its affiliates, or with respect to which it or any of its subsidiaries has the power to cause to be voted. If Novartis US, Purchaser, or any other subsidiary of Novartis US acquires at least 90% of the

41

outstanding Shares pursuant to the Offer, the Merger will be consummated pursuant to Section 253 of the DGCL without a meeting of the Company stockholders and without the approval of the Company stockholders. In the event that less than a majority of the Public Shares are tendered in the Offer, the Merger Agreement provides that the standstill provisions of the Confidentiality Agreement will be amended to provide that Novartis US and its subsidiaries will be permitted to make acquisitions of Shares that are voluntary to the holders of Shares (such as by means of legally permissible open market purchases or additional tender offers) but may consummate a merger or other business combination with the Company prior to February 11, 2006, only if: (1) holders representing a majority of the then-outstanding Public Shares approve such transaction; or (2) Novartis US and its subsidiaries at such time own 90% or more of the total outstanding Shares, provided that the price per Share paid in any such transaction described in (2) above is at least equal to the Offer Price. See Subsection 12(b)—"The Merger Agreement—Revised Standstill."

        The certificate of incorporation of Purchaser as in effect immediately prior to the Effective Time will be amended in its entirety to read the same as the certificate of incorporation of the Surviving Corporation until amended as provided therein or by applicable law, and the by-laws of Purchaser as in effect immediately prior to the Effective Time will be amended in its entirety to read the same as the by-laws of the Surviving Corporation until amended as provided therein, in the Surviving Corporation's certificate of incorporation or in accordance with applicable law. The indemnification and exculpation provisions of the certificate of incorporation and by-laws of the Company as in effect on February 20, 2005 will be included in the certificate of incorporation and by-laws of the Surviving Corporation and may not be amended, repealed or otherwise modified for a period of six years from the Acceptance Date in any manner that would adversely affect the rights under those provisions of all present and former directors, officers or employees of the Company.

13.  Source and Amount of Funds.

        The Offer is not subject to any financing condition. Novartis AG or an affiliate of Novartis AG will contribute or otherwise advance a sufficient amount of funds to Purchaser to consummate the Offer. Novartis AG will obtain the required funds from cash on hand. We will need approximately $977 million to purchase all of the Shares we are offering to purchase pursuant to the Offer (assuming the exercise of all outstanding Company Options) and to pay related fees and expenses.

14.  Dividends and Distributions.

        Under the Merger Agreement, the Company agreed not to (1) split, combine or reclassify its outstanding shares of capital stock; (2) declare, set aside or pay any dividend payable in cash, stock or property in respect of any capital stock (other than dividends from its direct or indirect wholly owned subsidiaries to it or a wholly owned subsidiary in the ordinary course of business); (3) repurchase, redeem or otherwise acquire any shares of its capital stock or any securities convertible into or exchangeable or exercisable for any shares of its capital stock or permit any of its subsidiaries to purchase or otherwise acquire any shares of its capital stock or any securities convertible into or exchangeable or exercisable for any shares of its capital stock; or (4) make any other change in its capital structure.

        Further, pursuant to the Santo Agreement, Santo agreed to use its best efforts to cause the Company not to (1) declare, set aside or pay any dividends on, or make any other distributions in respect of, any of its capital stock, other than dividends and distributions by any subsidiary of the Company to the Company; (2) split, combine or reclassify any of its capital stock, or issue or authorize the issuance of any other securities, including in respect of, in lieu of or in substitution for shares of its capital stock; (3) purchase, redeem or otherwise acquire any shares of its capital stock or any rights, warrants or options to acquire any such shares or other securities; or (4) take any action to transfer value from the Company to Santo or its other affiliates.

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        Nonetheless, if, on or after the date of this Offer to Purchase, the Company should split, combine or otherwise change the Shares or its capitalization, acquire or otherwise cause a reduction in the number of outstanding Shares or issue or sell any additional Shares (other than Shares issued pursuant to and in accordance with the terms in effect on the date of this Offer to Purchase of employee stock options outstanding prior to such date), shares of any other class or series of capital stock, other voting securities or any securities convertible into, or options, rights, or warrants, conditional or otherwise, to acquire, any of the foregoing, then, without prejudice to our rights under Section 15—"Conditions to the Offer," we may, in our sole discretion, make such adjustments in the Offer Price and other terms of the Offer as we deem appropriate, including the number or Shares to be purchased.

15.  Conditions to the Offer.

        Notwithstanding any other provisions of the Offer (subject to the terms and conditions of the Merger Agreement and any applicable rules and regulations of the SEC, including Exchange Act Rule 14e-1(c), Novartis US will cause Purchaser to accept for payment and pay for any Public Share tendered pursuant to the Offer, subject only to the Tender Offer Conditions:

(1)

the contemporaneous (or immediately subsequent) purchase of the Santo Shares pursuant to the Santo Agreement, and



(2)

satisfaction of all requirements of any applicable United States or foreign, federal, state or local law, statute, ordinance, rule, regulation, judgment, order, injunction, decree, agency requirement, license or permit of any United States or foreign federal, state or local governmental or regulatory authority, agency, commission, body or other governmental entity.

        Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase, including consummation of the transactions contemplated by the Hexal Agreement, is effectively an indirect condition to the Offer. See Subsection 12(c)—"The Santo Agreement—Closing Conditions."

        The existence or satisfaction of any of the Tender Offer Conditions will be determined by Novartis AG, Novartis US and Purchaser in their sole discretion. The foregoing conditions are for the sole benefit of Novartis AG, Novartis US and Purchaser, and Novartis AG, Novartis US or Purchaser may assert the failure of any of the Tender Offer Conditions regardless of the circumstances giving rise to any such failure (other than any circumstance arising solely by any action or inaction by Novartis AG, Novartis US or Purchaser). Novartis AG, Novartis US and Purchaser further reserve the right to waive in whole or in part (to the extent legally permissible) any of the Tender Offer Conditions in their sole discretion at any time, and from time to time, prior to the expiration of the Offer. The failure by Novartis AG, Novartis US or Purchaser at any time to exercise any of the foregoing rights will not be deemed a waiver of any such right; the waiver of any such right with respect to particular facts and other circumstances will not be deemed a waiver with respect to any other facts and circumstances; and each such right will be deemed an ongoing right that may be asserted at any time and from time to time prior to the expiration of the Offer. Any determination by Novartis AG, Novartis US or Purchaser concerning the events described in this Section will be final and binding on all parties.

16.  Certain Legal Matters; Regulatory Approvals.

        General.    We are not aware of any governmental license or regulatory permit that appears to be material to the Company's business that might be adversely affected by our acquisition of Shares pursuant to the Offer or, except as set forth below, of any approval or other action by any

43

government or governmental, administrative or regulatory authority or agency, domestic or foreign, that would be required for our acquisition or ownership of Shares pursuant to the Offer. Should any such approval or other action be required, we currently contemplate that such approval or other action will be sought. There can be no assurance that any such approval or other action, if needed, would be obtained. Our obligation under the Offer to accept for payment and pay for Shares is subject only to the conditions set forth in Section 15—"Conditions to the Offer."

        The Company is incorporated under the laws of the State of Delaware and has its principal place of business in the State of New York. A number of states have adopted takeover laws and regulations that purport to be applicable to attempts to acquire securities of corporations that are incorporated in those states or that have substantial assets, stockholders, principal executive offices or principal places of business in those states. Except as described in this Offer to Purchase, we have not attempted to comply with any state takeover statutes in connection with either the Offer or the Merger. We reserve the right to challenge the validity or applicability of any state law allegedly applicable to the Offer or the Merger, and nothing in this Offer to Purchase nor any action that we take in connection with the Offer is intended as a waiver of that right. In the event that it is asserted that one or more takeover statutes apply to the Offer or the Merger, and it is not determined by an appropriate court that the statutes in question do not apply or are invalid as applied to the Offer or the Merger, as applicable, we may be required to file certain documents with, or receive approvals from, the relevant state authorities, and we might be unable to accept for payment or purchase Shares tendered in the Offer or be delayed in continuing or consummating the Offer. In that case, we may not be obligated to accept for purchase, or pay for, any Shares tendered. See Section 15—"Conditions to the Offer."

Antitrust

United States.    Under the HSR Act, and the rules that have been promulgated thereunder by the Federal Trade Commission (the "FTC"), certain acquisition transactions may not be consummated unless certain information has been furnished to the Antitrust Division of the Department of Justice (the "Antitrust Division") and the FTC and certain waiting period requirements have been satisfied. The purchase of the Santo Shares and Shares pursuant to the Offer are subject to such requirements.

        Pursuant to the requirements of the HSR Act, on March 7, 2005, Novartis US filed Notification and Report Forms on behalf of Novartis AG with respect to the Santo Purchase and the Offer with the Antitrust Division and the FTC and on April 6, 2005, the FTC issued a request for additional information to both Novartis AG and Santo. Novartis AG and Santo are cooperating with the FTC's request for additional information. Therefore, the waiting period applicable to the purchase of Santo Shares and Shares pursuant to the Offer will be extended until 11:59 p.m., New York City time, on the thirtieth day after substantial compliance with such request by Novartis AG and Santo unless terminated earlier by the FTC. If the thirtieth day is on a weekend or holiday, the waiting period is extended until 11:59 p.m. on the next business day. Thereafter, such waiting period can be extended only by court order or as agreed to by Novartis AG and Santo.

        Expiration or early termination of the applicable waiting period under the HSR Act is a specific Tender Offer Condition, as it is a requirement of law for the consummation of the Offer. In addition, such expiration or early termination is effectively an indirect condition to the consummation of the Offer because such expiration is a condition to the consummation of the purchase of the Santo Shares under the Santo Agreement and one of the Tender Offer Conditions is the contemporaneous or immediately subsequent purchase by Novartis US (or its designee) of the Santo Shares. Therefore, Shares will not be accepted for payment or paid for pursuant to the Offer until the expiration or early termination of the applicable waiting period under the HSR Act.

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        The Antitrust Division and the FTC frequently scrutinize the legality under the antitrust laws of transactions such as our acquisition of the Santo Shares and Shares pursuant to the Offer. At any time before or after the consummation of any such transactions, the Antitrust Division or the FTC could take such action under the antitrust laws as it deems necessary or desirable in the public interest, including seeking to enjoin the purchase of the Santo Shares and Shares pursuant to the Offer or seeking divestiture of the Santo Shares and Shares acquired pursuant to the Offer, or divestiture of the Company or Novartis AG's material assets. Novartis AG and Santo are cooperating with the FTC's review of the purchase of the Santo Shares and the Shares pursuant to the Offer and Novartis AG believes that the FTC's approval to consummate such transactions will be obtained. However, there can be no assurance that a challenge to the Santo Purchase or the Offer on antitrust grounds will not be made, or if such a challenge is made, what the result will be. See Section 15—"Conditions to the Offer," for certain conditions to the Offer.

Other Countries.    Regulatory approvals from the European Union, South Africa and Turkey will be required prior to the consummation of the transactions contemplated by the Hexal Agreement. Although the approvals from the European Union, South Africa and Turkey are not specific Tender Offer Conditions, they are effectively indirect conditions to the consummation of the Offer as approval under certain other countries' antitrust or trade regulation laws is a condition to the consummation of the transactions contemplated by the Hexal Agreement, and the closing of the Santo Purchase is conditioned upon the prior or contemporaneous closing of the transactions contemplated by the Hexal Agreement. Therefore, because one of the Tender Offer Conditions is the contemporaneous or immediately subsequent purchase by Novartis US of the Santo Shares, no Shares will be accepted for payment or paid for pursuant to the Offer until the foreign regulatory approvals required to consummate the transactions contemplated by the Hexal Agreement have been obtained. Further, in the event that the approval of the European Union referred to above does not extend to the Santo Purchase and the Offer, regulatory approval will need to be obtained from Germany with respect to the Santo Purchase and the Offer.

        Novartis AG and its affiliates are in the process of seeking all such regulatory approvals, other than with respect to Germany which Novartis AG and its affiliates will seek if such approval becomes necessary. However, there can be no assurance that all such approvals will be obtained.

Section 203

        Subject to certain exceptions, Delaware's business combination statute set forth in Section 203 of the DGCL prohibits a business combination with an interested stockholder for three years following such time as the stockholder becomes an interested stockholder. An interested stockholder is any person that individually or through any of its affiliates and associates owns 15% of more of a corporation's total outstanding voting shares. Novartis AG, Novartis US and Purchaser do not believe that Section 203 of the DGCL is applicable to any of the Santo Purchase, the Offer or the Merger. In any event, the Company Board has, and the Company has represented in the Merger Agreement that it has, taken all action necessary to exempt the Santo Purchase, the Offer, the Merger, the Merger Agreement and the transactions contemplated thereby from the provisions of Section 203 of the DGCL, if applicable.

17.  Fees and Expenses.

        Goldman Sachs is acting as the Dealer Manager in connection with the Offer and as financial advisor to Novartis in connection with the Offer and the Merger. In such capacity, Novartis has agreed to pay Goldman Sachs reasonable and customary compensation for its services and will reimburse them for certain out-of-pocket expenses. Novartis has agreed to indemnify Goldman Sachs and related parties against certain liabilities and expenses in connection with Goldman Sachs's engagement, including certain liabilities under the United States federal securities laws. In

45

the ordinary course of business Goldman Sachs, its successors and affiliates may trade Shares for their own accounts and accounts of customers, and, accordingly, may at any time hold a long or short position in the Shares.

        We have retained Georgeson Shareholder Communications Inc. as Information Agent in connection with the Offer. The Information Agent may contact holders of Shares by mail, telephone, telex, telegraph and personal interview and may request brokers, dealers and other nominee stockholders to forward material relating to the Offer to beneficial owners of Shares. We will pay the Information Agent reasonable and customary compensation for these services in addition to reimbursing the Information Agent for its reasonable out-of-pocket expenses. We have agreed to indemnify the Information Agent against certain liabilities and expenses in connection with the Offer.

        In addition, we have retained ComputerShare Trust Company, Inc. as the Depositary. We will pay the Depositary reasonable and customary compensation for its services in connection with the Offer, will reimburse the Depositary for its reasonable out-of-pocket expenses and will indemnify the Depositary against certain liabilities and expenses.

        Except as set forth above, we will not pay any fees or commissions to any broker, dealer or other person for soliciting tenders of Shares pursuant to the Offer. We will reimburse brokers, dealers, commercial banks and trust companies and other nominees, upon request, for customary clerical and mailing expenses incurred by them in forwarding offering materials to their customers.

18.  Legal Proceedings.

        On February 22, 2005, Paulena Partners LLC, a purported holder of Shares, filed a class action complaint (the "Paulena Partners Action") in the Court of Chancery of the State of Delaware, County of New Castle (the "Delaware Court"), purportedly on behalf of itself and all others similarly situated, against the Company, the Company Board, Purchaser, Novartis US and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Santo Agreement and the Offer. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Santo Agreement and the Offer, unspecified compensatory damages or rescissory damages in the event the Offer is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On February 22, 2005, Ellen Wiehl, a purported holder of Shares, filed a class action complaint (the "Wiehl Action") in the Delaware Court, purportedly on behalf of herself and all others similarly situated, against the Company, the Company Board, and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Merger Agreement and the transactions contemplated thereby, including the Offer. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Offer and the Merger, unspecified compensatory damages or rescissory damages in the event the Offer and the Merger are consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On February 22, 2005, Robert Kemp, a purported holder of Shares, filed a class action complaint (the "Kemp Action") in the Delaware Court, purportedly on behalf of himself and all others similarly situated, against the Company, the Company Board, and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Offer and the Merger Agreement. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Offer, unspecified compensatory damages or rescissory

46

damages in the event the Offer is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On February 23, 2005, Peter J. Calcagno, a purported holder of Shares, filed a class action complaint (the "Calcagno Action") in the Delaware Court, purportedly on behalf of himself and all others similarly situated, against the Company, the Company Board, and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Offer and the Merger Agreement. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Offer, unspecified compensatory damages or rescissory damages in the event the Offer is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On February 23, 2005, Christopher Pizzo, a purported holder of Shares, filed a class action complaint in the Supreme Court of the State of New York, County of New York, purportedly on behalf of himself and all others similarly situated, against the Company, the Company Board, Novartis US and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Offer and the Merger Agreement. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Merger, unspecified compensatory damages or rescissory damages in the event the Merger is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On March 1, 2005, Erste Sparinvest Kapitalanlagegesellschaft MBH, a purported holder of Shares, filed a class action complaint (the "Sparinvest Action") in the Delaware Court, purportedly on behalf of itself and all others similarly situated, against the Company, the Company Board, and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Offer and the Merger Agreement. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Offer, unspecified compensatory damages or rescissory damages in the event the Offer is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On March 1, 2005, Merl Huntsinger, a purported holder of Shares, filed a class action complaint (the "Huntsinger Action") in the Delaware Court, purportedly on behalf of himself and all others similarly situated, against the Company, the Company Board, Novartis US, Purchaser and Santo. The complaint alleged breaches of fiduciary duty in connection with the Offer, the Merger Agreement and the grant of Company Options to certain officers and directors of the Company in February 2005, as well as breach of the Company's certificate of incorporation in connection with the Company's agreement under the Merger Agreement to replace the Company Board with Purchaser's designees. According to the complaint, the plaintiff sought, among other things, an order enjoining the consummation of the Offer and the Merger, an order rescinding and invalidating the Company Options granted in February 2005, unspecified compensatory or rescissory damages in the event the Offer is consummated, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

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        On March 3, 2005, Jason Hung, a purported holder of Shares, filed a class action complaint (the "Hung Action") in the Delaware Court, purportedly on behalf of himself and all others similarly situated, against the Company, the Company Board and Novartis AG. The complaint alleges self-dealing and breach of fiduciary duty in connection with the Offer and the Merger Agreement. According to the complaint, the plaintiff seeks, among other things, an order enjoining the consummation of the Offer and the Merger, unspecified rescissory damages in the event the Offer and the Merger are consummated, unspecified compensatory damages, and an unspecified amount for the costs and disbursements of the lawsuit, including reasonable attorneys' and experts' fees. The complaint is filed as an exhibit to the Tender Offer Statement on Schedule TO that has been filed with the SEC; please refer to that Exhibit for additional information.

        On March 1, 2005, plaintiff in the Huntsinger Action moved in the Delaware Court for expedited proceedings as well as a preliminary injunction preventing Purchaser, the Company and Novartis US from effectuating the Offer and the Merger. At a hearing on March 4, 2005, the Delaware Court denied the motion for expedited proceedings. Also on March 4, plaintiffs in the Wiehl Action, the Paulena Partners Action, the Kemp Action, the Calcagno Action, the Sparinvest Action and the Hung Action moved in the Delaware Court for an order consolidating their lawsuits with the Huntsinger Action and designating two of the law firms that filed the lawsuits other than the Huntsinger Action as co-lead counsel. On March 22, 2005, the Delaware Court ordered plaintiffs' counsel in all of the actions that were the subject of the motion to consolidate to convene an organizational meeting and adopt an organizational structure for prosecution of such actions. On April 8, 2005, plaintiff in the Huntsinger Action voluntarily dismissed his lawsuit without prejudice and advised the Delaware Court that neither he nor his counsel wished to participate in the litigation in any way. On April 12, 2005, the Delaware Court issued an order consolidating the Wiehl Action, the Paulena Partners Action, the Calcagno Action, the Sparinvest Action and the Hung Action into a single action and directing that defendants need not respond to the complaints previously filed in the constituent actions. It is anticipated that plaintiffs will file a consolidated amended complaint.

19.  Miscellaneous.

        The Offer is not being made to, nor will tenders be accepted from or on behalf of, holders of Shares in any jurisdiction in which the making of the Offer or acceptance thereof would not be in compliance with the laws of such jurisdiction. However, we may, in our discretion, take such action as we may deem necessary to make the Offer in any such jurisdiction and extend the Offer to holders of Shares in such jurisdiction.

        No person has been authorized to give any information or make any representation on behalf of Novartis AG, Novartis US or Purchaser not contained in this Offer to Purchase or in the related Letter of Transmittal and, if given or made, such information or representation must not be relied upon as having been authorized.

        We have filed with the SEC a Tender Offer Statement on Schedule TO, together with exhibits, pursuant to Exchange Act Rules 14d-3, which contain certain additional information with respect to the Offer. The Tender Offer Statement on Schedule TO and any amendments thereto, including exhibits, may be examined and copies may be obtained from the offices of the SEC in the manner set forth in Section 9—"Certain Information Concerning the Company" of this Offer to Purchase.

	Zodnas Acquisition Corp.
May 23, 2005

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SCHEDULE I

DIRECTORS AND EXECUTIVE OFFICERS
OF
NOVARTIS AG, NOVARTIS US AND PURCHASER

        The name, current principal occupation or employment and material occupations, positions, offices or employment for the past five years of each director and executive officer of Novartis AG, Novartis US and Purchaser are set forth below. References herein to "Novartis US" mean Novartis Corporation, and references herein to "Purchaser" mean Zodnas Acquisition Corp.

Directors and Executive Officers of Novartis AG

        Unless otherwise indicated, each occupation set forth below refers to employment with Novartis AG. Unless otherwise indicated below, the business address of each director and officer is c/o Novartis AG, 35 Lichtstrasse, CH-4002 Basel, Switzerland.

Name, Function and Business Address	Citizenship	Principal Occupation and Five-Year Employment History
Daniel Vasella Chairman of the Board of Directors, Chief Executive Officer	Switzerland	Chairman of the Board of Directors (since 1999), Chief Executive Officer (since 1996). Mr. Vasella is a member of the Board of Directors of PepsiCo Inc., the Board of Directors of Associates of Harvard Business School, and the Chairman's Council of DaimlerChrysler AG, Germany. Mr. Vasella is also President of the International Federation of Pharmaceutical Manufacturers Associations, a member of the International Board of Governors of the Peres Center for Peace in Israel, and a member of the International Business Leaders Advisory Council for the Mayor of Shanghai. He also serves as a member of several industry associations and educational institutions.
Hans-Jorg Rudloff Vice Chairman of the Board of Directors	Germany	Chairman of the Executive Committee of Barclays Capital. Positions at Novartis AG: Vice Chairman of the Board (since 1996); member of the Chairman's Committee and the Compensation Committee (since 1999); member of the Corporate Governance Committee (since 2002); member of the Audit and Compliance Committee (since 2004). Mr. Rudloff also serves on a number of boards of other companies, including the Boards of Directors of the TBG Group (Thyssen-Bornemisza Group), Marcuard Group, RBC, and ADB Consulting. Mr. Rudloff is a member of the Advisory Board of the MBA program of the University of Bern, of Landeskreditbank Baden-Württemberg and of EnBW (Energie Baden-Württemberg).

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Prof. Dr. Helmut Sihler Vice Chairman of the Board of Directors	Austria	Retired. Positions at Novartis AG: Vice Chairman of the Board (since 1996); Lead Director (since 1999); member of the Chairman's Committee and the Corporate Governance Committee; Chairman of the Audit and Compliance Committee and of the Compensation Committee. Mr. Sihler is also Chairman of the Supervisory Board of Dr. Ing. h.c. F. Porsche AG Germany.
Birgit Breuel Director	Germany	Member of the Supervisory Board of Gruner + Jahr AG. Positions at Novartis AG: Director (since 1996); member of the Audit and Compliance Committee (since 1999). Ms. Breuel is also a member of the Supervisory Board of WWF and of HGV (Hamburger Gesellschaft für Vermögensund Beteiligungsverwaltung mbH), Germany. In 1990, Ms. Breuel was elected to the Executive Board of the Treuhandanstalt; in 1991, she also became the President of the Treuhandanstalt. From 1995 to 2000, she acted as the General Commissioner and CEO of the world exhibition EXPO 2000 in Hanover, Germany.
Prof. Dr. Peter Burckhardt Director	Switzerland	Head of Department of Internal Medicine at the University Hospital of Lausanne. Positions at Novartis AG: Director (since 1996). From 1982 to 2004, Mr. Burckhardt was Chairman of the Novartis (formerly Sandoz) Foundation for Biomedical Research in Switzerland. Mr. Burckhardt is treasurer of the International Foundation of Osteoporosis. Since 1990, he has been the organizer and chairman of the International Symposia on Nutrition and Osteoporosis.

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Prof. Srikant Datar, Ph.D. Director	India	Senior Associate Dean for Executive Education at Harvard Business School and Arthur Lower Dickinson Professor at Harvard University. Positions with Novartis AG: Director (since 2003). Srikant Datar is a member of the Board of Voyan Technology Inc. and of Harvard Business School Interactive.
William W. George Director	USA	Professor of Management Practice at Harvard Business School. Positions with Novartis AG: Director (since 1999); member of the Chairman's Committee; Chairman of the Corporate Governance Committee. Mr. George is a member of the Boards of Directors of Goldman Sachs and Target Corporation. Mr. George served as President and Chief Operating Officer of Medtronic, Inc. and, from 1991 to 2001, as its Chief Executive Officer. From 1996 to 2002, he was Medtronic's Chairman. Mr. George has served as Executive-in-Residence at Yale School of Management and as Professor of Leadership and Governance at IMD International in Lausanne, Switzerland. In addition, he is a member of the Board of Directors of the National Association of Corporate Directors and of the Carnegie Endowment for International Peace.
Alexandre F. Jetzer Director	Switzerland	Consultant to Novartis International AG (Government Relations Support). Positions with Novartis AG: Director (since 1996). Mr. Jetzer is also a member of the Board of Directors of Clariden Bank of the Supervisory Board of Compagnie Financière Michelin and of the Board of the Lucerne Festival Foundation.

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Pierre Landoldt Director	Switzerland	President of the Sandoz Family Foundation; Chairman of the Board of Directors of Landolt Kapital SA; Chairman of the Board of Directors of Emasan AG. Positions with Novartis AG: Director (since 1996). Mr. Landolt is also a member of the Board of Directors of Syngenta AG, and of the Syngenta Foundation for Sustainable Agriculture. In addition, he serves as Chairman of the Boards of Directors of Curacao International Trust Company and Vaucher Manufacture Fleurier SA., and he serves as Vice Chairman of the Boards of Directors of Parmigiani, Mesur et Art du Temps S.A. and the Fondation du Montreux Jazz Festival. Since 1997 Mr. Landolt has been Associate and Chairman of Axial Par Ltda, São Paulo, a company investing in sustainability. In 2000, he was co-founder of Eco Carbone LLC, a company focused on the development of carbon sequestration processes in Europe, Africa and South America.
Prof. Dr. Rolf M. Zinkernagel Director	Switzerland	Professor and Director of the Institute of Experimental Immunology at the University of Zurich. Positions with Novartis AG: Director (since 1999); member of the Corporate Governance Committee (since 2001). Mr. Zinkernagel was a member of the Board of Directors of Cytos Biotechnology AG until April 2003. He is also a member of the Scientific Advisory Boards of The Lombard Odier, Darier Hentsch & Cie Bank, BT & T, Bio-Alliance AG, Aravis General Partner Ltd., Cytos Biotechnology AG, Bioxell, Esbatech, Novimmune, Miikana Therapeutics, Cancevir and Mann-Kind. Mr. Zinkernagel is also a Science Consultant to GenPat77, Aponetics AG, Solis Therapeutics, Ganymed and Zhen-Ao Group.

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Prof. Ulrich Lehner, Ph.D. Director	Germany	President and Chief Executive Officer of Henkel KGaA. Positions with Novartis AG: Director (since 2002); member of the Audit and Compliance Committee; Audit Committee Financial Expert. Mr. Lehner also serves as a member of the Board of Ecolab Inc., as a member of the supervisory boards of E.ON AG and of HSBC Trinkaus & Burkhardt KGaA. Mr. Lehner is a member of the Advisory Board of Dr. August Oetker KG and of Krombacher Brauerei. He is an Honorary Professor at the University of Münster. From 1995 to 2000, he served Henkel KGaA as Executive Vice President, Finance/Logistics (CFO).
Dr.-Ing. Wendelin Wiedeking Director	Germany	Chairman of the Executive Board of Dr. Ing. h.c. F. Porsche AG. Positions with Novartis AG: Director (since 2003). Mr. Wiedeking is member of the Supervisory Board of Directors of Deutsche Telekom AG and of Eagle Picher Incorporated.
Dr. Raymund Breu	Switzerland	Chief Financial Officer (since 1996). Mr. Breu is also a member of the Board of Directors of Swiss Re, Chiron, the SWX Swiss Exchange and its admission panel and the Swiss takeover commission.
Dr. Urs Baerlocher	Switzerland	Head of Legal and General Affairs (since 2000).
Jurgen Brokatzky-Geiger	Germany	Head of Human Resources (since 2003). Mr. Brokatzky-Geiger was Global Head of Technical R&D from 1999–2003.
Dr. Paul Choffat	Switzerland	Head of Novartis Consumer Health (since 2002). Mr. Choffat was a private investor and entrepreneur from 1999–2002.

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Thomas Ebeling	Germany	Head of Pharmaceuticals (since 2000).
Mark C. Fishman	USA	Head of Biomedical Research. Before joining Novartis, Mark C. Fishman was Professor of Medicine at Harvard Medical School and Chief of Cardiology and Director of the Cardiovascular Research Center at the Massachusetts General Hospital in Boston.
Steven Kelmar	USA	Head of Public Affairs and Communications (since 2003). Mr. Kelmar was the Senior Vice President of External Relations at Medtronic, Inc. from 1997–2003.
Andreas Rummelt	Germany	Chief Executive Officer of Sandoz GmbH (since 2004). Prior to becoming the CEO of Sandoz, Mr. Rummelt was Head of Global Technical Operations at Novartis Pharma AG from 1994 to 2004 and was a Member of the Pharma Executive Committee.

Directors and Executive Officers of Novartis US

        Unless otherwise indicated, each occupation set forth below refers to employment with Novartis US. Unless otherwise indicated below, the business address of each director and officer is c/o Novartis Corporation, 608 Fifth Avenue, New York, NY 10020.

Name, Function and Business Address	Citizenship	Principal Occupation and Five-Year Employment History
Daniel Vasella Chairman of the Board of Directors c/o Novartis AG Lichtstrasse 35 CH-4002 Basel, Switzerland	Switzerland	Chairman of the Board of Directors of Novartis AG (since 1999), Chief Executive Officer of Novartis AG (since 1996). Mr. Vasella is a member of the Board of Directors of PepsiCo Inc., the Board of Directors of Associates of Harvard Business School, and the Chairman's Council of DaimlerChrysler AG, Germany. Mr. Vasella is also President of the International Federation of Pharmaceutical Manufacturers Associations, a member of the International Board of Governors of the Peres Center for Peace in Israel, and a member of the International Business Leaders Advisory Council for the Mayor of Shanghai. He also serves as a member of several industry associations and educational institutions.

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Terence Barnett Vice Chairman of the Board of Directors	Great Britain	Vice Chairman, President and Chief Executive Officer (since 1999).
Dr. Raymund Breu Director c/o Novartis AG Lichstrasse 35 CH-4002 Basel, Switzerland	Switzerland	Chief Financial Officer of Novartis AG (since 1996).
Thomas Ebeling Director c/o Novartis AG Lichstrasse 35 CH-4002 Basel, Switzerland	Germany	Chief Executive Officer of Novartis Pharma AG (since 2000).
Fred Meyer Director c/o Omnicom Group, Inc. 437 Madison Avenue New York, NY 10022, USA	Switzerland	Retired.
Urs Naegelin Executive Vice President and Chief Financial Officer	Switzerland	Executive Vice President and Chief Financial Officer (since 2000).
Dr. Paul Choffat Division Head Consumer Health c/o Novartis AG Lichstrasse 35 CH-4002 Basel, Switzerland	Switzerland	Head of Novartis Consumer Health (since 2002). Mr. Choffat was a private investor and entrepreneur from 1999–2002.
Dr. Martin Henrich Executive Vice President, Regional General Counsel and Secretary	Switzerland	Executive Vice President, Regional General Counsel and Secretary (since 2001). Mr. Henrich was Head of Tax, M&A and Finance for Novartis Group at Novartis International AG from 1996–2001.

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Directors and Executive Officers of Purchaser

        Unless otherwise indicated, each occupation set forth below refers to employment with Purchaser. Unless otherwise indicated below, the business address of each director and officer is c/o Novartis Corporation, 608 Fifth Avenue, New York, NY 10020.

Name, Function and Business Address	Citizenship	Principal Occupation and Five-Year Employment History
Terence Barnett Chairman of the Board of Directors	Great Britain	Vice Chairman, President and Chief Executive Officer of Novartis US (since 1999).
Urs Naegelin Director, Vice President	Switzerland	Executive Vice President and Chief Financial Officer of Novartis US (since 2000).
Martin Henrich Director, Vice President and Assistant Secretary	Switzerland	Executive Vice President, Regional General Counsel and Secretary of Novartis US (since 2001). Mr. Henrich was Head of Tax, M&A and Finance for Novartis Group at Novartis International AG from 1996-2001.
John Sedor President (until May 20, 2005) 506 Carnegie Center, Suite 400 Princeton, NJ 08540, USA	USA	President and Chief Executive Officer of Sandoz Inc. (since 2001). Mr. Sedor was President and Chief Executive Officer of Verion, Inc. from 1998–2001.
Eric Gorka President (as of May 18, 2005)	Netherlands	President and Chief Executive Officer of Sandoz Inc. (since April 2005). Mr. Gorka was the President and Chief Executive Officer of Sandoz BeNeLux from 2003-2005 and the President and Chief Executive Officer of Sandoz Netherlands from 1999–2003.
Eric W. Evans Vice President and Chief Financial Officer 506 Carnegie Center, Suite 400 Princeton, NJ 08540, USA	USA	Vice President and Chief Financial Officer of Sandoz Inc. (since 2001). Mr. Evans was Vice President and Controller of The LTV Corporation from 1993–2001.
Eric Pomerantz Vice President and Secretary 506 Carnegie Center, Suite 400 Princeton, NJ 08540, USA	USA	Vice President and General Counsel of Sandoz Inc. (since 2002). Mr. Pomerantz was Vice President, General Counsel & Secretary of Novartis Animal Health US, Inc. from 1997–2002.
Wayne P. Merkelson Vice President and Assistant Secretary	USA	Vice President and Associate General Counsel of Novartis US (since 1989).

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        Manually signed facsimile copies of the Letter of Transmittal will be accepted. The Letter of Transmittal and certificates for Shares and any other required documents should be sent to the Depositary at one of the addresses set forth below:

The Depositary for the Offer is:

By Mail:	By Facsimile (for Eligible Institutions only):	By Hand or Overnight Courier:
Computershare Trust Company of New York Wall Street Station P.O. Box 1010 New York, NY 10268-1010	For Eligible Institutions Only: (212) 701-7636 For Confirmation Only Telephone: (212) 701-7600	Computershare Trust Company of New York Wall Street Plaza 88 Pine Street, 19th Floor New York, NY 10005

        Any questions or requests for assistance may be directed to the Information Agent or the Dealer Manager at their respective addresses or telephone numbers set forth below. Additional copies of the Offer to Purchase, the Letter of Transmittal and the Notice of Guaranteed Delivery may be obtained from the Information Agent at its address and telephone numbers set forth below. Holders of Shares may also contact their broker, dealer, commercial bank or trust company or other nominee for assistance concerning the Offer.

The Information Agent for the Offer is:

17 State Street, 10^th Floor
New York, NY 10004
Stockholders Call Toll Free: (877) 278-4774
Banks and Brokerage Firms Call: (212) 440-9800

The Dealer Manager for the Offer is:

Goldman, Sachs & Co.

85 Broad Street
New York, New York 10004
(212) 902-1000 (Call Collect)
(800) 323-5678 (Call Toll Free)

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TABLE OF CONTENTS
SUMMARY TERM SHEET
FORWARD-LOOKING STATEMENTS
INTRODUCTION
THE OFFER
SCHEDULE I DIRECTORS AND EXECUTIVE OFFICERS OF NOVARTIS AG, NOVARTIS US AND PURCHASER

EX-99.(A)(1)(B)

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Exhibit (a)(1)(B)

LETTER OF TRANSMITTAL
TO TENDER SHARES OF COMMON STOCK
OF
Eon Labs, Inc.
PURSUANT TO THE OFFER TO PURCHASE DATED MAY 23, 2005
BY
Zodnas Acquisition Corp.
an indirect wholly owned subsidiary
OF
Novartis AG
THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00
MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005,
UNLESS THE OFFER IS EXTENDED.

The Depositary for the Offer is:

By Mail:	By Facsimile:	By Hand or Overnight Courier:
Computershare Trust Company of New York Wall Street Station P.O. Box 1010 New York, NY 10268-1010	For Eligible Institutions Only: (212) 701-7636 For Confirmation Only Telephone: (212) 701-7600	Computershare Trust Company of New York Wall Street Plaza 88 Pine Street, 19th Floor New York, NY 10005

DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE DOES NOT CONSTITUTE A VALID DELIVERY. YOU MUST SIGN THIS LETTER OF TRANSMITTAL WHERE INDICATED BELOW AND COMPLETE THE SUBSTITUTE FORM W-9 PROVIDED BELOW.

THE INSTRUCTIONS ACCOMPANYING THIS LETTER OF TRANSMITTAL SHOULD BE READ CAREFULLY BEFORE THIS LETTER OF TRANSMITTAL IS COMPLETED.

DESCRIPTION OF SHARES TENDERED
Name(s) and Address(es) of Registered Holder(s) (Please Fill in, if Blank)		Share Certificate(s) and Share(s) Tendered (Attach Additional Signed List, if Necessary)
		Share Certificate Number(s)*	Total Number of Shares Represented by Share Certificate(s)*	Number of Shares Tendered**
		Total Shares Tendered
*	Certificate numbers are not required if tender is made by book-entry transfer.
**	If you desire to tender fewer than all Shares represented by any certificate listed above, please indicate in this column the number of Shares you wish to tender. Otherwise, all Shares represented by such certificate will be deemed to have been tendered. See Instruction 4.

        This Letter of Transmittal is to be completed by stockholders of Eon Labs, Inc. if certificates ("Share Certificates") representing shares of common stock of Eon Labs, Inc., par value $0.01 per share (the "Shares"), are to be forwarded with this Letter of Transmittal. An Agent's Message (as defined below) is to be utilized if delivery of Shares is to be made by book-entry transfer to an account maintained by ComputerShare Trust Company, Inc. (the "Depositary") at The Depository Trust Company (the "Book-Entry Transfer Facility") pursuant to the procedures set forth under Section 4—"Procedure for Tendering Shares" of the Offer to Purchase dated May 23, 2005 (the "Offer to Purchase"). Delivery of documents to the Book-Entry Transfer Facility in accordance with the Book-Entry Transfer Facility's procedures does not constitute delivery to the Depositary.

        Stockholders whose Share Certificates are not immediately available or who cannot deliver their Share Certificates and all other required documents to the Depositary on or prior to the expiration date of the Offer or who are unable to complete the procedure for book-entry transfer on or prior to the expiration date of the Offer may nevertheless tender their Shares pursuant to the guaranteed delivery procedures set forth under Section 4—"Procedure for Tendering Shares" of the Offer to Purchase. See Instruction 2.

2

o

CHECK HERE IF SHARES ARE BEING DELIVERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE DEPOSITARY AND COMPLETE THE FOLLOWING. PLEASE ENCLOSE A PHOTOCOPY OF SUCH NOTICE OF GUARANTEED DELIVERY.

        Name(s) of Registered Holder(s):

        Window Ticket Number (if any):

        Date of Execution of Notice of Guaranteed Delivery:

        Name of Institution which Guaranteed Delivery:

        If Delivered by Book-Entry Transfer to the Book-Entry Transfer Facility, check box: o

        Account Number:

        Transaction Code Number:

NOTE: SIGNATURE(S) MUST BE PROVIDED BELOW.
PLEASE READ THE INSTRUCTIONS SET FORTH IN THIS LETTER OF TRANSMITTAL CAREFULLY.

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Ladies and Gentlemen:

        The undersigned hereby tenders to Zodnas Acquisition Corp., a Delaware corporation ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation, a New York corporation ("Novartis US"), an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, the above-described shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation (the "Company"), pursuant to Purchaser's offer to purchase any and all outstanding Shares at $31.00 per Share, net to the seller in cash, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated May 23, 2005 (the "Offer to Purchase"), receipt of which is hereby acknowledged, and in this Letter of Transmittal (which, together with the Offer to Purchase and any amendments or supplements to the Offer to Purchase or to this Letter of Transmittal, collectively constitute the "Offer").

        Subject to, and effective upon, acceptance for payment of the Shares tendered with this Letter of Transmittal, in accordance with the terms of the Offer, the undersigned hereby sells, assigns and transfers to, or upon the order of, Purchaser all right, title and interest in and to all the Shares that are being tendered by this Letter of Transmittal and all dividends, distributions (including, without limitation, distributions of additional Shares) and rights declared, paid or distributed in respect of such Shares on or after May 23, 2005 (collectively, "Distributions") and irrevocably appoints ComputerShare Trust Company, Inc. (the "Depositary") the true and lawful agent, attorney-in-fact and proxy of the undersigned with respect to such Shares and all Distributions, with full power of substitution (such power of attorney being deemed to be an irrevocable power coupled with an interest), to (i) deliver certificates representing Shares ("Share Certificates") and all Distributions, or transfer ownership of such Shares and all Distributions on the account books maintained by the Book-Entry Transfer Facility, together, in either case, with all accompanying evidences of transfer and authenticity, to or upon the order of Purchaser; (ii) present such Shares and all Distributions for transfer on the books of the Company; and (iii) receive all benefits and otherwise exercise all rights of beneficial ownership of such Shares and all Distributions, all in accordance with the terms and subject to the conditions of the Offer.

        The undersigned hereby irrevocably appoints the designees of Purchaser, and each of them, as agents, attorneys-in-fact and proxies of the undersigned, each with full power of substitution, to vote in such manner as such attorney and proxy or his substitute shall, in his sole discretion, deem proper and otherwise act (by written consent or otherwise) with respect to all the Shares tendered by this Letter of Transmittal which have been accepted for payment by Purchaser prior to the time of such vote or other action and all Shares and other securities issued in Distributions in respect of such Shares, which the undersigned is entitled to vote at any meeting of stockholders of the Company (whether annual or special and whether or not an adjourned or postponed meeting) or consent in lieu of any such meeting or otherwise. This proxy and power of attorney are coupled with an interest in the Shares tendered by this Letter of Transmittal, are irrevocable and are granted in consideration of, and are effective upon, the acceptance for payment of such Shares by Purchaser in accordance with the terms of the Offer. Such acceptance for payment shall revoke all other proxies and powers of attorney granted by the undersigned at any time with respect to such Shares (and all Shares and other securities issued in Distributions in respect of such Shares), and no subsequent proxy or power of attorney shall be given or written consent executed (and if given or executed, shall not be effective) by the undersigned with respect to such Shares (and all Shares and other securities issued in Distributions in respect of such Shares). The undersigned understands that, in order for Shares to be deemed validly tendered, immediately upon Purchaser's acceptance of such Shares for payment, Purchaser must be able to exercise full voting and other rights with respect to such Shares, including, without limitation, voting at any meeting of the Company's stockholders then scheduled.

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        The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer the Shares tendered by this Letter of Transmittal and all Distributions, and that when such Shares are accepted for payment by Purchaser, Purchaser will acquire good, marketable and unencumbered title to such Shares and to all Distributions, free and clear of all liens, restrictions, charges and encumbrances, and that none of such Shares and Distributions will be subject to any adverse claim. The undersigned, upon request, shall execute and deliver all additional documents deemed by the Depositary or Purchaser to be necessary or desirable to complete the sale, assignment and transfer of the Shares tendered by this Letter of Transmittal and all Distributions. In addition, the undersigned shall remit and transfer promptly to the Depositary for the account of Purchaser all Distributions in respect of the Shares tendered by this Letter of Transmittal, accompanied by appropriate documentation of transfer, and pending such remittance and transfer or appropriate assurance thereof, Purchaser shall be entitled to all rights and privileges as owner of each such Distribution and may withhold the entire purchase price of the Shares tendered by this Letter of Transmittal, or deduct from such purchase price, the amount or value of such Distribution as determined by Purchaser in its sole discretion.

        No authority conferred or agreed to be conferred in this Letter of Transmittal shall be affected by, and all such authority shall survive, the death or incapacity of the undersigned. All obligations of the undersigned under this Letter of Transmittal shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned. Except as stated in the Offer to Purchase, this tender is irrevocable. See Section 5—"Withdrawal Rights" of the Offer to Purchase.

        The undersigned understands that tenders of Shares pursuant to any one of the procedures described in the Offer to Purchase under Section 4—"Procedure for Tendering Shares" and in the instructions to this Letter of Transmittal will constitute the undersigned's acceptance of the terms and conditions of the Offer. Purchaser's acceptance of such Shares for payment will constitute a binding agreement between the undersigned and Purchaser upon the terms and subject to the conditions of the Offer. Without limiting the foregoing, if the price to be paid in the Offer is amended in accordance with the Offer, the price to be paid to the undersigned will be the amended price notwithstanding the fact that a different price is stated in this Letter of Transmittal. The undersigned recognizes that under certain circumstances set forth in the Offer to Purchase, Purchaser may not be required to accept for payment any of the Shares tendered by this Letter of Transmittal.

        Unless otherwise indicated in this Letter of Transmittal in the box entitled "Special Payment Instructions," please issue the check for the purchase price of all Shares purchased, and return all Share Certificates not purchased or not tendered, in the name(s) of the registered holder(s) appearing above under "Description of Shares Tendered." Similarly, unless otherwise indicated in the box entitled "Special Delivery Instructions," please mail the check for the purchase price of all Shares purchased and all Share Certificates not tendered or not purchased (and accompanying documents, as appropriate) to the address(es) of the registered holder(s) appearing above under "Description of Shares Tendered." In the event that the boxes entitled "Special Payment Instructions" and "Special Delivery Instructions" are both completed, please issue the check for the purchase price of all Shares purchased and return all Share Certificates not purchased or not tendered in the name(s) of, and mail such check and Share Certificates to, the person(s) so indicated. Please credit any Shares tendered by this Letter of Transmittal and delivered by book-entry transfer, but which are not purchased, by crediting the account at the Book-Entry Transfer Facility. The undersigned recognizes that Purchaser has no obligation, pursuant to the Special Payment Instructions, to transfer any Shares from the name of the registered holder(s) of such Shares if Purchaser does not purchase any of the Shares tendered by this Letter of Transmittal.

5

LOST SHARE CERTIFICATES:

PLEASE CALL AMERICAN STOCK TRANSFER & TRUST COMPANY AT (800) 937-5449 OR (718) 921-8124 TO OBTAIN NECESSARY DOCUMENTS TO REPLACE YOUR LOST SHARE CERTIFICATES.

SPECIAL PAYMENT INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)

            To be completed ONLY if Share Certificates not tendered or not purchased and/or the check for the purchase price of the Shares purchased are to be issued in the name of and sent to someone other than the undersigned.

Issue o check and/or o certificates to:

Name(s):	(Please Print)
Address(es):
(Include Zip Code)
(Taxpayer Identification or Social Security No.) (See Substitute Form W-9)

SPECIAL DELIVERY INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)

            To be completed ONLY if Share Certificates not tendered or not purchased and/or the check for the purchase price of the Shares purchased are to be sent to someone other than the undersigned, or to the undersigned at an address other than that shown above.

Issue o check and/or o certificates to:

Name(s):	(Please Print)
Address(es):
(Include Zip Code)

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IMPORTANT
STOCKHOLDER: SIGN HERE
(And Please Complete Substitute Form W-9 Included Herein)

Signature(s) of Holder(s)
Dated:	, 2005
Must be signed by registered holder(s) exactly as name(s) appear(s) on Share Certificate(s) or on a security position listing or by person(s) authorized to become registered holder(s) by Share Certificate(s) and documents transmitted with this Letter of Transmittal. If a signature is by an officer on behalf of a corporation or by an executor, administrator, trustee, guardian, attorney-in-fact, agent or other person acting in a fiduciary or representative capacity, please set forth full title. See Instructions 1 and 5.

Name(s):

(Please Print)

Capacity (full title):

Address:

(Include Zip Code)

Daytime Area Code and Telephone Number:

Taxpayer Identification or
Social Security No.:	(See Substitute Form W-9)

GUARANTEE OF SIGNATURE(S)
(If Required—See Instructions 1 and 5)

Authorized Signature
Name (Please Print)
Name of Firm
Address
Zip Code
(Area Code) Telephone No.
Dated:	, 2005

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INSTRUCTIONS

Forming Part of the Terms And Conditions of the Offer

        To complete the Letter of Transmittal you must do the following:

        — Fill in the box entitled "Description of Shares Being Tendered."

        — Sign and date the Letter of Transmittal in the box entitled "Sign Here."

        — Fill in and, sign in the box entitled "Substitute Form W-9."

        In completing the Letter of Transmittal, you may (but are not required to) also do the following:

        — If you want the payment for any Shares purchased issued in the name of another person, complete the box entitled "Special Payment Instructions."

        — If you want any certificate for Shares not tendered or Shares not purchased issued in the name of another person, complete the box entitled "Special Payment Instructions."

        — If you want any payment for Shares or certificate for Shares not tendered or purchased delivered to an address other than that appearing under your signature, complete the box entitled "Special Delivery Instructions."

        If you complete the box entitled "Special Payment Instructions" or "Special Delivery Instructions," you must have your signature guaranteed by an Eligible Institution (as defined in Instruction 1 below) unless the Letter of Transmittal is signed by an Eligible Institution.

1.     Guarantee of Signatures. All signatures on this Letter of Transmittal must be guaranteed by a bank, broker, dealer, credit union, savings association or other entity that is a member in good standing of the Securities Transfer Agents Medallion Program or any other "Eligible Guarantor Institution," as defined in Rule l7Ad-l5 of the Securities Exchange Act of 1934, as amended (each, an "Eligible Institution" and collectively "Eligible Institutions"), unless (i) this Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this document, shall include any participant in a Book-Entry Transfer Facility whose name appears on a security position listing as the owner of Shares) of the Shares tendered by this Letter of Transmittal and such holder(s) has not completed either the box entitled "Special Payment Instructions" or the box entitled "Special Delivery Instructions" in this Letter of Transmittal or (ii) such Shares are tendered for the account of an Eligible Institution. If a Share Certificate is registered in the name of a person other than the person signing this Letter of Transmittal, or if payment is to be made, or a Share Certificate not accepted for payment and not tendered is to be returned to a person other than the registered holder(s), then such Share Certificate must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name(s) of the registered holder(s) appear on such Share Certificate, with the signatures on such Share Certificate or stock powers guaranteed as described above. See Instruction 5.

2.     Delivery of Letter of Transmittal and Share Certificates. This Letter of Transmittal is to be used if Share Certificates are to be forwarded with this Letter of Transmittal. If an Agent's Message (as defined below) is used, Shares are to be delivered by book-entry transfer pursuant to the procedure set forth under Section 4—"Procedure for Tendering Shares" in the Offer to Purchase. Share Certificates representing all physically tendered Shares, or confirmation of a book-entry transfer, if such procedure is available, into the Depositary's account at the Book-Entry Transfer Facility ("Book-Entry Confirmation") of all Shares delivered by book-entry transfer together with a properly completed and duly executed Letter of Transmittal (or facsimile thereof), or an Agent's Message in the case of book-entry transfer, and any other documents required by this Letter of Transmittal, must be received by the Depositary at one of its addresses set forth in this Letter of Transmittal on or prior to the expiration date of the Offer. If Share Certificates are forwarded

8

to the Depositary in multiple deliveries, a properly completed and duly executed Letter of Transmittal must accompany each such delivery.

        Stockholders whose Share Certificates are not immediately available, who cannot deliver their Share Certificates and all other required documents to the Depositary on or prior to the expiration date of the Offer or who cannot complete the procedure for delivery by book-entry transfer on a timely basis may tender their Shares pursuant to the guaranteed delivery procedure described under Section 4—"Procedure for Tendering Shares" in the Offer to Purchase. Pursuant to such procedure: (i) such tender must be made by or through an Eligible Institution; (ii) a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form made available by Purchaser, must be received by the Depositary on or prior to the expiration date of the Offer; and (iii) the Share Certificates representing all physically delivered Shares in proper form for transfer by delivery, or Book-Entry Confirmation of all Shares delivered by book-entry transfer, in each case together with a Letter of Transmittal (or facsimile thereof), properly completed and duly executed, with any required signature guarantees (or, in the case of a book-entry transfer, an Agent's Message), and any other documents required by this Letter of Transmittal, must be received by the Depositary within three Nasdaq National Market trading days after the date of execution of such Notice of Guaranteed Delivery, all as described under Section 4—"Procedure for Tendering Shares" in the Offer to Purchase.

        The term "Agent's Message" means a message transmitted by a Book-Entry Transfer Facility to, and received by, the Depositary and forming a part of a Book-Entry Confirmation, which message states that the Book-Entry Transfer Facility has received an express acknowledgment from the participant in the Book-Entry Transfer Facility tendering the Shares that are the subject of the Book-Entry Confirmation that the participant has received and agrees to be bound by the terms of this Letter of Transmittal and that Purchaser may enforce that agreement against the participant.

The method of delivery of this Letter of Transmittal, Share Certificates and all other required documents, including delivery through the Book-Entry Transfer Facility, is at the option and risk of the tendering stockholder, and the delivery will be deemed to be made only when actually received by the Depositary (including, in the case of a Book-Entry Transfer, by Book-Entry Confirmation). If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

        No alternative, conditional or contingent tenders will be accepted and no fractional Shares will be purchased. By execution of this Letter of Transmittal (or facsimile thereof), all tendering stockholders waive any right to receive any notice of the acceptance of their Shares for payment.

3.     Inadequate Space. If the space provided in this Letter of Transmittal under "Description of Shares Tendered" is inadequate, the certificate numbers, the number of Shares represented by such Share Certificates and the number of Shares tendered should be listed on a separate schedule and attached to this Letter of Transmittal.

4.     Partial Tenders (Not Applicable to Stockholders who Tender by Book-Entry Transfer). If fewer than all the Shares represented by any Share Certificate delivered to the Depositary with this Letter of Transmittal are to be tendered by this Letter of Transmittal, fill in the number of Shares which are to be tendered in the box entitled "Number of Shares Tendered." In such cases, a new certificate representing the remainder of the Shares that were represented by the Share Certificates delivered to the Depositary with this Letter of Transmittal will be sent to each person signing this Letter of Transmittal, unless otherwise provided in the box entitled "Special Delivery Instructions" in this Letter of Transmittal as soon as practicable after the expiration or termination of the Offer. All Shares represented by Share Certificates delivered to the Depositary will be deemed to have been tendered unless otherwise indicated.

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5.     Signatures on Letter of Transmittal, Stock Powers and Endorsements. If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered by this Letter of Transmittal, the signature(s) must correspond with the name(s) as written on the face of the Share Certificates evidencing such Shares without alteration, enlargement or any other change whatsoever.

        If any Share tendered by this Letter of Transmittal is owned of record by two or more persons, all such persons must sign this Letter of Transmittal.

        If any of the Shares tendered by this Letter of Transmittal are registered in the names of different holders, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of such Shares.

        If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered by this Letter of Transmittal, no endorsements of Share Certificates or separate stock powers are required, unless payment is to be made to, or Share Certificates not tendered or not purchased are to be issued in the name of, a person other than the registered holder(s), in which case, the Share Certificate(s) representing the Shares tendered by this Letter of Transmittal must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name(s) of the registered holder(s) appear on such Share Certificate(s). Signatures on such Share Certificate(s) and stock powers must be guaranteed by an Eligible Institution.

        If this Letter of Transmittal is signed by a person other than the registered holder(s) of the Shares tendered by this Letter of Transmittal, the Share Certificate(s) representing the Shares tendered by this Letter of Transmittal must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name(s) of the registered holder(s) appear(s) on such Share Certificate(s). Signatures on such Share Certificate(s) and stock powers must be guaranteed by an Eligible Institution.

        If this Letter of Transmittal or any certificate or stock power is signed by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other person acting in a fiduciary or representative capacity, such person should so indicate when signing, and proper evidence satisfactory to Purchaser of such person's authority to so act must be submitted.

6.     Stock Transfer Taxes. Except as otherwise provided in this Instruction 6, Purchaser will pay all stock transfer taxes with respect to the sale and transfer of any Shares to it or its order pursuant to the Offer. If, however, payment of the purchase price of any Shares purchased is to be made to, or Share Certificate(s) representing Shares not tendered or not purchased are to be issued in the name of, a person other than the registered holder(s), the amount of any stock transfer taxes (whether imposed on the registered holder(s), such other person or otherwise) payable on account of the transfer to such other person will be deducted from the purchase price of such Shares purchased, unless evidence satisfactory to Purchaser of the payment of such taxes, or exemption therefrom, is submitted.

Except as provided in this Instruction 6, it will not be necessary for transfer tax stamps to be affixed to the Share Certificates representing the Shares tendered by this Letter of Transmittal.

7.     Special Payment and Delivery Instructions. If a check for the purchase price of any Shares tendered by this Letter of Transmittal is to be issued, or Share Certificate(s) representing Shares not tendered or not purchased are to be issued, in the name of a person other than the person(s) signing this Letter of Transmittal or if such check or any such Share Certificate is to be sent to someone other than the person(s) signing this Letter of Transmittal or to the person(s) signing this Letter of Transmittal but at an address other than that shown in the box entitled "Description of Shares Tendered" in this Letter of Transmittal, the appropriate boxes in this Letter of Transmittal must be completed.

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8.     Waiver of Conditions. The conditions of the Offer may be waived, in whole or in part, by Purchaser, in its sole discretion, at any time and from time to time, in the case of any Shares tendered. See Section 15—"Conditions to the Offer" of the Offer to Purchase.

9.     Lost, Destroyed or Stolen Certificates. If any Share Certificate(s) have been lost, destroyed or stolen, the stockholder should promptly notify American Stock Transfer & Trust Company at (800) 937-5449 or (718) 921-8124. The stockholder will then be provided with instructions as to the procedures for replacing the Share Certificate(s). This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost, destroyed or stolen certificates have been followed and completed.

10.  Questions and Requests for Assistance or Additional Copies. Questions and requests for assistance may be directed to the Information Agent at its address or telephone numbers set forth below. Additional copies of the Offer to Purchase, this Letter of Transmittal, the Notice of Guaranteed Delivery and the Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 may be obtained from the Information Agent or from brokers, dealers, commercial banks or trust companies.

11.  Substitute Form W-9. Each tendering stockholder is required to provide the Depositary with the stockholder's correct Taxpayer Identification Number ("TIN"), generally the stockholder's social security or federal employer identification number, on the Substitute Form W-9, which is provided under "Important Tax Information" below, or, alternatively, to establish another basis for exemption from backup withholding. A tendering stockholder must cross out item (2) in the Certification box of the Substitute Form W-9 if such stockholder is subject to backup withholding. In addition to potential penalties, failure to provide the correct information on the Substitute Form W-9 may subject the tendering stockholder to 28% federal income tax backup withholding on any reportable payments made to such stockholder. If the tendering stockholder has not been issued a TIN and has applied for one or intends to apply for one in the near future, such stockholder should write "Applied For" in the space provided for the TIN in Part I of the Substitute Form W-9, and sign and date the Substitute Form W-9 and the Certificate of Awaiting Taxpayer Identification Number. If "Applied For" is written in Part I and the Depositary is not provided with a TIN by the time of payment, the Depositary will withhold 28% from any payments of the purchase price to such stockholder. A tendering stockholder that is not a United States person may qualify as an exempt recipient by submitting to the Depositary a properly completed Form W-8BEN, Form W-8ECI or Form W-8IMY, as applicable (which the Depositary will provide upon request) signed under penalty of perjury, attesting to that stockholder's exempt status.

IMPORTANT: THIS LETTER OF TRANSMITTAL (OR FACSIMILE THEREOF), TOGETHER WITH ANY REQUIRED SIGNATURE GUARANTEES, OR, IN THE CASE OF A BOOK-ENTRY TRANSFER, AN AGENT'S MESSAGE, AND ANY OTHER REQUIRED DOCUMENTS, MUST BE RECEIVED BY THE DEPOSITARY ON OR PRIOR TO THE EXPIRATION DATE OF THE OFFER, AND EITHER SHARE CERTIFICATES FOR TENDERED SHARES MUST BE RECEIVED BY THE DEPOSITARY OR SHARES MUST BE DELIVERED PURSUANT TO THE PROCEDURES FOR BOOK-ENTRY TRANSFER, IN EACH CASE ON OR PRIOR TO THE EXPIRATION DATE OF THE OFFER, OR THE TENDERING STOCKHOLDER MUST COMPLY WITH THE PROCEDURES FOR GUARANTEED DELIVERY.

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IMPORTANT TAX INFORMATION

        A stockholder whose tendered Shares are accepted for payment is required to provide the Depositary with such stockholder's correct TIN on the Substitute Form W-9 below or otherwise establish a basis for exemption from backup withholding. If such stockholder is an individual, the TIN is such stockholder's social security number. If the Depositary is not provided with the correct TIN or an adequate basis for exemption, payments made to such stockholder with respect to Shares purchased pursuant to the Offer may be subject to backup withholding and the stockholder may be subject to a penalty imposed by the Internal Revenue Service.

        Certain stockholders (including, among others, corporations and certain foreign persons) are not subject to these backup withholding and reporting requirements. Exempt stockholders should indicate their exempt status on the Substitute Form W-9. A foreign person may qualify as an exempt recipient by submitting to the Depositary a properly completed Internal Revenue Service Form W-8BEN, Form W-8ECI or Form W-8IMY, as applicable (instead of a Substitute Form W-9), signed under penalties of perjury, attesting to such stockholder's exempt status. Stockholders are urged to consult their own tax advisors to determine whether they are exempt from these backup withholding and reporting requirements.

        If backup withholding applies, the Depositary is required to withhold 28% of any payments made to the stockholder or other payee. Backup withholding is not an additional federal income tax. If the required information is furnished to the Internal Revenue Service in a timely manner, the federal income tax liability of persons subject to backup withholding may be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund may be obtained from the Internal Revenue Service.

Purpose of Substitute Form W-9

        To prevent backup withholding on any payments that are made to a stockholder with respect to Shares purchased pursuant to the Offer, the stockholder is required to provide the Depositary with (i) the stockholder's correct TIN by completing the form below, certifying (x) that the TIN provided on the Substitute Form W-9 is correct (or that the stockholder is awaiting a TIN), (y) that (A) the stockholder is exempt from backup withholding, (B) the stockholder has not been notified by the Internal Revenue Service that the stockholder is subject to backup withholding as a result of a failure to report all interest or dividends, or (C) the Internal Revenue Service has notified the stockholder that the stockholder is no longer subject to backup withholding, and (z) that such stockholder is a U.S. person (including a U.S. resident alien), or (ii) if applicable, an adequate basis for exemption.

What Number to Give the Depositary

        The stockholder is required to give the Depositary the TIN (e.g., social security number or employer identification number) of the record holder of the Shares tendered by this Letter of Transmittal. If the Shares are in more than one name or are not in the name of the actual owner, consult the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 for additional guidance on which number to report.

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        The Substitute Form W-9 BELOW must be completed and signed. PLEASE PROVIDE YOUR SOCIAL SECURITY NUMBER OR OTHER TAXPAYER IDENTIFICATION NUMBER ("TIN") AND CERTIFY THAT YOU ARE NOT SUBJECT TO BACKUP WITHHOLDING.

Substitute Form W-9 Department of the Treasury Internal Revenue Service Payer's Request for TIN and Certification
Name:
Please check the appropriate box indicating your status: o Individual/Sole proprietor  o Corporation  o Partnership  o Other		o Exempt from backup withholding
Address (number, street, and apt. or suite no.)
City, state, and ZIP code
Part I    TIN
PLEASE PROVIDE YOUR TIN ON THE APPROPRIATE LINE AT THE RIGHT.    For most individuals, this is your social security number. If you do not have a number, see the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9. If you are awaiting a TIN, write "Applied For" in this Part I, complete the "Certificate Of Awaiting Taxpayer Identification Number" below and see "IMPORTANT TAX INFORMATION".		Social Security Number OR      Employer Identification Number
Part II    Certification
Under penalties of perjury, I certify that:
(1)    The number shown on this form is my correct Taxpayer Identification Number (or I am waiting for a number to be issued to me), and
(2)    I am not subject to backup withholding because (a) I am exempt from backup withholding, or (b) I have not been notified by the IRS that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding, and
(3)    I am a U.S. person (including a U.S. resident alien).
Certification Instructions—You must cross out item (2) above if you have been notified by the IRS that you are currently subject to backup withholding because you have failed to report all interest and dividends on your tax return.
The IRS does not require your consent to any provision of this document other than the certifications required to avoid backup withholding.
Sign Here	Signature of U.S. person >	Date >

NOTE: FAILURE TO COMPLETE AND RETURN THE SUBSTITUTE FORM W-9 MAY RESULT IN BACKUP WITHHOLDING OF 28% OF ANY PAYMENTS MADE TO YOU ON ACCOUNT OF THE OFFER. PLEASE REVIEW THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS, AND PLEASE SEE "IMPORTANT TAX INFORMATION".

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        COMPLETE THE FOLLOWING CERTIFICATION IF YOU WROTE
"APPLIED FOR"
INSTEAD OF A TIN ON THE SUBSTITUTE FORM W-9.

CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER
I certify under penalties of perjury that a taxpayer identification number has not been issued to me, and either (a) I have mailed or delivered an application to receive a TIN to the appropriate Internal Revenue Service Center or Social Security Administration Office or (b) I intend to mail or deliver an application in the near future. I understand that if I do not provide a TIN by the time of payment, 28% of all reportable payments made to me will be withheld.
Sign Here	Signature of U.S. person >	Date >

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        You may direct questions and requests for assistance to the Information Agent at its address and telephone numbers set forth below. You may obtain additional copies of this Offer to Purchase, the Letter of Transmittal and other tender offer materials from the Information Agent as set forth below, and they will be furnished promptly at our expense. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance concerning the Offer.

The Information Agent for the Offer is:

17 State Street, 10^th Floor
New York, NY 10004
Stockholders Call Toll Free: (877) 278-4774
Banks and Brokerage Firms Call: (212) 440-9800

The Dealer Manager for the Offer is:

Goldman, Sachs & Co.

85 Broad Street
New York, New York 10004
Call Collect: (212) 902-1000
Call Toll Free: (800) 323-5678

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INSTRUCTIONS Forming Part of the Terms And Conditions of the Offer
IMPORTANT TAX INFORMATION

EX-99.(A)(1)(C)

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Exhibit (a)(1)(C)

NOTICE OF GUARANTEED DELIVERY
FOR TENDER OF SHARES OF COMMON STOCK

OF

Eon Labs, Inc.

PURSUANT TO THE OFFER TO PURCHASE DATED MAY 23, 2005

BY

Zodnas Acquisition Corp.

an indirect wholly owned subsidiary

OF

Novartis AG

(NOT TO BE USED FOR SIGNATURE GUARANTEES)

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK
CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

        This Notice of Guaranteed Delivery, or one substantially equivalent to this Notice of Guaranteed Delivery, must be used to accept the Offer (as defined below) if certificates for Shares (as defined below) are not immediately available or the certificates for Shares and all other required documents cannot be delivered to ComputerShare Trust Company, Inc. (the "Depositary") on or prior to the Expiration Date (as defined in the Offer to Purchase (as defined below)) or if the procedure for delivery by book-entry transfer cannot be completed on a timely basis. This instrument may be delivered by hand or transmitted by facsimile transmission or mailed to the Depositary. See Section 4—"Procedure for Tendering Shares" of the Offer to Purchase.

The Depositary for the Offer is:

By Mail:	By Facsimile:	By Hand or Overnight Courier:
Computershare Trust Company of New York Wall Street Station P.O. Box 1010 New York, NY 10268-1010	For Eligible Institutions Only: (212) 701-7636 For Confirmation Only Telephone: (212) 701-7600	Computershare Trust Company of New York Wall Street Plaza 88 Pine Street, 19th Floor New York, NY 10005

DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA FACSIMILE TRANSMISSION OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY TO THE DEPOSITARY.

THIS FORM IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS TO THE LETTER OF TRANSMITTAL, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX IN THE LETTER OF TRANSMITTAL.

THE GUARANTEE ON THE REVERSE SIDE MUST BE COMPLETED.

Ladies and Gentlemen:

        The undersigned hereby tender(s) to Zodnas Acquisition Corp., a Delaware corporation ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation ("Novartis US"), a New York corporation, an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated May 23, 2005 (the "Offer to Purchase"), and in the related Letter of Transmittal (which, together with the Offer to Purchase and any amendments or supplements to the Offer to Purchase or to the Letter of Transmittal, collectively constitute the "Offer"), receipt of which is hereby acknowledged, the number of shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation, indicated below pursuant to the guaranteed delivery procedure set forth in Section 4—"Procedure for Tendering Shares" of the Offer to Purchase.

Name(s) of Record Holder(s)

Address(es)

Zip Code

(Area Code) Telephone Number

X

X

Signature(s) of Record Holder(s)

Number of Shares
Certificate Number(s) (if available)
Indicate account number at Book-Entry Transfer Facility if Shares will be tendered by book-entry transfer:
Account Number
Dated:	, 2005
Dated:	, 2005

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GUARANTEE
(NOT TO BE USED FOR SIGNATURE GUARANTEE)

        The undersigned, a bank, broker, dealer, credit union, savings association or other entity that is a member in good standing of the Securities Transfer Agents Medallion Program or any other "eligible guarantor institution," as defined in Rule 17Ad-15 of the Securities Exchange Act of 1934, as amended (each, an "Eligible Institution" and collectively "Eligible Institutions"), hereby guarantees the delivery to the Depositary, at one of its addresses set forth above, of the certificates evidencing all Shares tendered by this Notice of Guaranteed Delivery in proper form for transfer, or confirmation of the book-entry transfer of Shares into the Depositary's account at The Depository Trust Company, in either case together with delivery of a properly completed and duly executed Letter of Transmittal (or a facsimile thereof) with any required signature guarantee, or an Agent's Message (as defined in the Offer to Purchase), and any other documents required by the Letter of Transmittal, within three Nasdaq National Market trading days after the date of execution of this Notice of Guaranteed Delivery.

        The Eligible Institution that completes this form must communicate the guarantee to the Depositary and must deliver the Letter of Transmittal and Share Certificates to the Depositary within the time period indicated herein. Failure to do so may result in financial loss to such Eligible Institution.

	X
Name of Firm	Authorized Signature
Address	Name (Please Print)
Zip Code	Title

	Dated:	, 2005
(Area Code) Telephone Number

NOTE: DO NOT SEND SHARE CERTIFICATES WITH THIS NOTICE.
SHARE CERTIFICATES SHOULD BE SENT WITH YOUR LETTER OF TRANSMITTAL.

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QuickLinks

NOTICE OF GUARANTEED DELIVERY FOR TENDER OF SHARES OF COMMON STOCK OF Eon Labs, Inc. PURSUANT TO THE OFFER TO PURCHASE DATED MAY 23, 2005 BY Zodnas Acquisition Corp. an indirect wholly owned subsidiary OF Novartis AG (NOT TO BE USED FOR SIGNATURE GUARANTEES)
The Depositary for the Offer is
THE GUARANTEE ON THE REVERSE SIDE MUST BE COMPLETED.

EX-99.(A)(1)(D)

Exhibit (a)(1)(D)

OFFER TO PURCHASE FOR CASH
ANY AND ALL OUTSTANDING SHARES OF COMMON STOCK
OF
Eon Labs, Inc.
BY
Zodnas Acquisition Corp.
an indirect wholly owned subsidiary
OF
Novartis AG
AT
$31.00 NET PER SHARE

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

May 23, 2005

To Brokers, Dealers, Commercial Banks,
Trust Companies and Other Nominees:

        We have been appointed by Novartis Corporation ("Novartis US"), a New York corporation and an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, to act as Information Agent in connection with Zodnas Acquisition Corp.'s (an indirect wholly owned subsidiary of Novartis US) ("Purchaser") offer to purchase for cash any and all outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation (the "Company"), at a purchase price of $31.00 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated May 23, 2005 (the "Offer to Purchase"), and in the related Letter of Transmittal (which, together with the Offer to Purchase and any amendments or supplements to the Offer to Purchase or to the Letter of Transmittal, collectively constitute the "Offer") enclosed herewith. Holders of Shares whose certificates for such Shares (the "Share Certificates") are not immediately available or who cannot deliver their Share Certificates and all other required documents to the Depositary (as defined below) on or prior to the Expiration Date (as defined in the Offer to Purchase), or who cannot complete the procedure for book-entry transfer on a timely basis, must tender their Shares according to the guaranteed delivery procedures set forth in Section 4—"Procedure for Tendering Shares" of the Offer to Purchase.

        Please furnish copies of the enclosed materials to those of your clients for whose accounts you hold Shares registered in your name or in the name of your nominee.

        Enclosed herewith for your information and forwarding to your clients are copies of the following documents:

1.

The Offer to Purchase, dated May 23, 2005.



2.

The Letter of Transmittal to tender Shares for your use and for the information of your clients. Facsimile copies of the Letter of Transmittal may be used to tender Shares.



3.

The Notice of Guaranteed Delivery for Shares to be used to accept the Offer if Share Certificates are not immediately available or if such certificates and all other required documents cannot be delivered to ComputerShare Trust Company, Inc. (the "Depositary")

on or prior to the Expiration Date or if the procedure for book-entry transfer cannot be completed on or prior to the Expiration Date.

4.

The letter to stockholders of the Company from Bernhard Hampl, Ph.D., Chief Executive Officer of the Company, accompanied by the Company's Solicitation/Recommendation Statement on Schedule 14D-9 filed with the United States Securities and Exchange Commission.



5.

A printed form of letter which may be sent to your clients for whose accounts you hold Shares registered in your name or in the name of your nominee with space provided for obtaining such clients' instructions with regard to the Offer.



6.

Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9.



7.

A return envelope addressed to ComputerShare Trust Company, Inc., as Depositary.

        YOUR PROMPT ACTION IS REQUESTED. WE URGE YOU TO CONTACT YOUR CLIENTS AS PROMPTLY AS POSSIBLE. PLEASE NOTE THAT THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

        The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designees of the 60,000,000 Shares owned by Santo Holding (Deutschland) GmbH ("Santo"), representing approximately 67.5% of the outstanding equity interest in the Company, pursuant to the Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and among Novartis US, Santo, and for purposes of Section 12 thereof only, Novartis AG (the "Santo Agreement," and such stock purchase, the "Santo Purchase"); and (2) satisfaction of all applicable legal requirements for consummating the Offer. See Section 15—"Conditions to the Offer" of the Offer to Purchase. Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase is indirectly a condition to the Offer. See Subsection 12(c)—"the Santo Agreement" of the Offer to Purchase.

        The Offer is being made solely by the Offer to Purchase and the related Letter of Transmittal, and is being made to all holders of Shares subject to the terms and conditions set forth in the Offer to Purchase. Novartis US and Purchaser are not aware of any jurisdiction where the making of the Offer is prohibited by any administrative or judicial action pursuant to any valid state statute. If Novartis US and Purchaser become aware of any valid state statute prohibiting the making of the Offer or the acceptance of the Shares, Novartis US and Purchaser will make a good faith effort to comply with that state statute. If, after a good faith effort, Novartis US and Purchaser cannot comply with the state statute, Purchaser will not make the Offer to, nor will Purchaser accept tenders from or on behalf of, Company stockholders in that state.

Both the Company's Board of Directors and a special committee of the Company's Board of Directors (the "Special Committee") consisting of independent directors not affiliated with Santo have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement (as defined in the Offer to Purchase), including the Offer and the Merger (as defined in the Offer to Purchase), is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the Delaware General Corporation Law, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders and (iv) taken all other action within the Board of Directors' and the Special Committee's power to render Section 203 of the Delaware General Corporation Law, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger.

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        In order to take advantage of the Offer, (1) a duly executed and properly completed Letter of Transmittal (or facsimile thereof) and any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase) in connection with a book-entry delivery of Shares, and other required documents should be sent to the Depositary, and (2) either Share Certificates representing the tendered Shares should be delivered to the Depositary or such Shares should be tendered by book-entry transfer and a Book-Entry Confirmation (as defined in the Offer to Purchase) with respect to such Shares should be delivered to the Depositary, all in accordance with the instructions set forth in the Letter of Transmittal and the Offer to Purchase.

        Holders of Shares whose Share Certificates are not immediately available or who cannot deliver their Share Certificates and all other required documents to the Depositary on or prior to the expiration date of the Offer, or who cannot complete the procedure for delivery by book-entry transfer on a timely basis, must tender their Shares according to the guaranteed delivery procedures set forth in Section 4 of the Offer to Purchase.

        Purchaser will not pay any commissions or fees to any broker, dealer or other person (other than the Depositary, Goldman, Sachs & Co. as the Dealer Manager for the Offer (the "Dealer Manager") and Georgeson Shareholder Communications Inc. (the "Information Agent") (as described in the Offer to Purchase)) for soliciting tenders of Shares pursuant to the Offer. Purchaser will, however, upon request, reimburse you for customary clerical and mailing expenses incurred by you in forwarding any of the enclosed materials to your clients. Purchaser will pay or cause to be paid any stock transfer taxes payable on the transfer of Shares to it, except as otherwise provided in Instruction 6 of the Letter of Transmittal.

        Any inquiries you may have with respect to the Offer should be addressed to the Information Agent at its address and telephone numbers set forth on the back cover of the Offer to Purchase. Additional copies of the enclosed materials may be obtained from the Information Agent.

Very truly yours,

Georgeson Shareholder Communications Inc.

Nothing contained herein or in the enclosed documents shall make you or any other person the agent of Purchaser, Novartis US, Novartis AG, the Depositary, the Dealer Manager or the Information Agent, or any affiliate of any of them, or authorize you or any other person to make any statement or use any document on behalf of any of them in connection with the offer other than the enclosed documents and the statements contained therein.

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EX-99.(A)(1)(E)

Exhibit (a)(1)(E)

OFFER TO PURCHASE FOR CASH
ANY AND ALL OUTSTANDING SHARES OF COMMON STOCK
OF
Eon Labs, Inc.
BY
Zodnas Acquisition Corp.
an indirect wholly owned subsidiary
OF
Novartis AG
AT
$31.00 NET PER SHARE

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

To Our Clients:

        Enclosed for your consideration is an Offer to Purchase dated May 23, 2005 (the "Offer to Purchase"), and the related Letter of Transmittal, relating to an offer by Zodnas Acquisition Corp., a Delaware corporation ("Purchaser"), an indirect wholly owned subsidiary of Novartis Corporation ("Novartis US"), a New York corporation, an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, to purchase for cash any and all outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation (the "Company"), at a purchase price of $31.00 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase and in the related Letter of Transmittal (which, together with the Offer to Purchase and any amendments or supplements to the Offer to Purchase or to the Letter of Transmittal, collectively constitute the "Offer") enclosed herewith. Holders of Shares whose certificates for such Shares (the "Share Certificates") are not immediately available or who cannot deliver their Share Certificates and all other required documents to the Depositary (as defined in the Offer to Purchase) on or prior to the Expiration Date (as defined in the Offer to Purchase), or who cannot complete the procedure for book-entry transfer on a timely basis, must tender their Shares according to the guaranteed delivery procedures set forth in Section 4—"Procedure for Tendering Shares" of the Offer to Purchase.

We are the holder of record of Shares held by us for your account. A tender of such Shares can be made only by us as the holder of record and pursuant to your instructions. The Letter of Transmittal is furnished to you for your information only and cannot be used by you to tender Shares held by us for your account.

        We request instructions as to whether you wish to have us tender on your behalf any or all of such Shares held by us for your account, pursuant to the terms and subject to the conditions set forth in the Offer to Purchase.

        Your attention is directed to the following:

1.

The Offer price is $31.00 per Share, net to the seller in cash, without interest thereon.



2.

The Offer is made for any and all issued and outstanding Shares.



3.

The Offer is being made pursuant to an Agreement and Plan of Merger, dated as of February 20, 2005 (the "Merger Agreement"), by and among Novartis US, Purchaser, the Company and, for purposes of Section 10.12 thereof only, Novartis AG. The Merger

Agreement provides, among other things, if a majority of the Public Shares (as defined in the Offer to Purchase) are tendered into the Offer, upon the terms and subject to the conditions of the Merger Agreement, and in accordance with the Delaware General Corporation Law, Purchaser will be merged with and into the Company (the "Merger"). Following the effective time of the Merger, the Company will continue as the surviving corporation and be an indirect wholly owned subsidiary of Novartis US and the separate corporate existence of Purchaser will cease.

4.

Both the Company's Board of Directors and a special committee of the Company's Board of Directors (the "Special Committee") consisting of independent directors not affiliated with Santo Holding (Deutschland) GmbH ("Santo"), which owns approximately 67.5% of the outstanding Shares and has agreed by separate agreement to sell its Shares to an affiliate of Novartis US, have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase (as defined below), the Offer, the Merger and the Merger Agreement in accordance with the Delaware General Corporation Law, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company's stockholders and (iv) taken all other action within the Board of Directors' and the Special Committee's power to render Section 203 of the Delaware General Corporation Law, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger.

5.

The Offer and withdrawal rights will expire at 12:00 midnight, New York City time, on June 20, 2005 unless the Offer is extended.



6.

Tendering stockholders will not be obligated to pay brokerage fees or commissions or, except as set forth in Instruction 6 of the Letter of Transmittal, stock transfer taxes on the purchase of Shares pursuant to the Offer.



7.

The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designees of the 60,000,000 Shares owned by Santo, representing approximately 67.5% of the outstanding equity interest in the Company, pursuant to the Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and among Novartis US, Santo, and for purposes of Section 12 thereof only, Novartis AG (the "Santo Agreement," and such stock purchase, the "Santo Purchase"); and (2) satisfaction of all applicable legal requirements for consummating the Offer. See Section 15—"Conditions to the Offer" of the Offer to Purchase. Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase is indirectly a condition to the Offer. See Subsection 12(c)—"The Santo Agreement" of the Offer to Purchase.

        The Offer is being made solely by the Offer to Purchase and the related Letter of Transmittal, and is being made to all holders of Shares. Novartis US and Purchaser are not aware of any jurisdiction where the making of the Offer is prohibited by any administrative or judicial action pursuant to any valid state statute. If Novartis US and Purchaser become aware of any valid state statute prohibiting the making of the Offer or the acceptance of the Shares, Novartis US and Purchaser will make a good faith effort to comply with that state statute. If, after a good faith effort, Novartis US and Purchaser cannot comply with the state statute, Purchaser will not make the Offer to, nor will Purchaser accept tenders from or on behalf of, Company stockholders in that state. In those jurisdictions where the securities, blue sky or other laws require the Offer to be made by a licensed broker or dealer, the Offer will be deemed to be made on behalf of the Purchaser by

2

Goldman, Sachs & Co., the Dealer Manager for the Offer, or one or more registered brokers or dealers licensed under the laws of such jurisdiction.

If you wish to have us tender any or all of the Shares held by us for your account, please instruct us by completing, executing and returning to us the instruction form contained in this letter. If you authorize a tender of your Shares, all such Shares will be tendered unless otherwise specified in such instruction form. Your instructions should be forwarded to us in ample time to permit us to submit a tender on your behalf on or prior to the Expiration Date of the Offer.

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INSTRUCTIONS WITH RESPECT TO THE
OFFER TO PURCHASE FOR CASH
ANY AND ALL OUTSTANDING SHARES OF COMMON STOCK
OF
Eon Labs, Inc.
BY
Zodnas Acquisition Corp.
an indirect wholly owned subsidiary
OF
Novartis AG
AT
$31.00 NET PER SHARE

The undersigned acknowledge(s) receipt of your letter enclosing the Offer to Purchase dated May 23, 2005 (the "Offer to Purchase"), and the related Letter of Transmittal, pursuant to an offer by Zodnas Acquisition Corp., a Delaware corporation, an indirect wholly owned subsidiary of Novartis Corporation, a New York corporation, an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, to purchase for cash any and all outstanding shares of common stock, par value $0.01 per share (the "Shares"), of Eon Labs, Inc., a Delaware corporation, at a purchase price of $31.00 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase and the related Letter of Transmittal.

This will instruct you to tender the number of Shares indicated below (or, if no number is indicated below, all Shares) which are held by you for the account of the undersigned, upon the terms and subject to the conditions set forth in the Offer to Purchase and in the related Letter of Transmittal furnished to the undersigned.

Number of Shares to be Tendered1
Dated:	, 2005
SIGN HERE
Signature(s)
Please Print
Address
Area Code and Telephone
Tax Identification or Social Security Number(s)

¹

Unless otherwise indicated, it will be assumed that all of your Shares held by us for your account are to be tendered.

EX-99.(A)(1)(F)

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Exhibit (a)(1)(F)

GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
NUMBER ON SUBSTITUTE FORM W-9

Guidelines for Determining the Proper Identification Number for the Payee (You) to Give the Payer—Social Security numbers have nine digits separated by two hyphens: i.e., 000-00-0000. Employer identification numbers have nine digits separated by only one hyphen: i.e., 00-0000000. The table below will help determine the number to give the payer. All "Section" references are to the Internal Revenue Code of 1986, as amended. "IRS" is the Internal Revenue Service.

For this type of account:		Give the name and Social Security number of—
1.	Individual	The individual
2.	Two or more individuals (joint account)	The actual owner of the account or, if combined funds, the first individual on the account(1)
3.	Custodian account of a minor (Uniform Gift to Minors Act)	The minor(2)
4.	a. The usual revocable savings trust (grantor is also trustee)	The grantor-trustee(1)
	b. So-called trust account that is not a legal or valid trust under state law	The actual owner(1)
5.	Sole proprietorship or single-owner LLC	The owner(3)
For this type of account:		Give the name and Employer Identification number of—
6.	Sole proprietorship or single-member LLC	The owner(3)
7.	A valid trust, estate, or pension trust	The legal entity(4)
8.	Corporate or LLC electing corporate status on Form 8832	The corporation
9.	Association, club, religious, charitable, educational, or other tax-exempt organization	The organization
10.	Partnership or multi-member LLC	The partnership
11.	A broker or registered nominee	The broker or nominee
12.	Account with the Department of Agriculture in the name of a public entity (such as a state or local government, school district, or prison) that receives agricultural program payments	The public entity

(1)

List first and circle the name of the person whose number you furnish. If only one person on a joint account has a social security number, that person's number must be furnished.

(2)

Circle the minor's name and furnish the minor's social security number.

(3)

You must show your individual name, but you may also enter your business or "doing business as" name. You may use either your social security number or your employer identification number (if you have one).

(4)

List first and circle the name of the legal trust, estate, or pension trust. (Do not furnish the taxpayer identification number of the personal representative or trustee unless the legal entity itself is not designated in the account title.)

NOTE: If no name is circled when there is more than one name listed, the number will be considered to be that of the first name listed.

GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
NUMBER ON SUBSTITUTE FORM W-9

Page 2

Obtaining a Number

If you do not have a taxpayer identification number, apply for one immediately. To apply for a SSN, get Form SS-5, Application for a Social Security Card, from your local Social Security Administration office. Get Form W-7, Application for IRS Individual Taxpayer Identification Number, to apply for a TIN, or Form SS-4, Application for Employer Identification Number, to apply for an EIN. You can get Forms W-7 and SS-4 from the IRS by calling 1 (800) TAX-FORM, or from the IRS Web Site at www.irs.gov.

Payees Exempt From Backup Withholding

Payees specifically exempted from backup withholding include:

1.

An organization exempt from tax under Section 501(a), an individual retirement account (IRA), or a custodial account under Section 403(b)(7) if the account satisfies the requirements of Section 401(f)(2).

2.

The United States or any of its agencies or instrumentalities.

3.

A state, the District of Columbia, a possession of the United States, or any of their political subdivisions or instrumentalities.

4.

A foreign government or any of its political subdivisions, agencies or instrumentalities.

5.

An international organization or any of its agencies or instrumentalities.

Payees that may be exempt from backup withholding include:

6.

A corporation.

7.

A foreign central bank of issue.

8.

A dealer in securities or commodities required to register in the United States, the District of Columbia, or a possession of the United States.

9.

A futures commission merchant registered with the Commodity Futures Trading Commission.

10.

A real estate investment trust.

11.

An entity registered at all times during the tax year under the Investment Company Act of 1940.

12.

A common trust fund operated by a bank under Section 584(a).

13.

A financial institution.

14.

A middleman known in the investment community as a nominee or custodian.

15.

A trust exempt from tax under Section 664 or described in Section 4947.

        The chart below shows types of payments that may be exempt from backup withholding. The chart applies to the exempt recipients listed above, 1 through 15.

If the payment is for…	THEN the payment is exempt for…
Interest and dividend payments	All exempt recipients except for 9
Broker transactions	Exempt recipients 1 through 13. Also, a person registered under the Investment Advisers Act of 1940 who regularly acts as a broker

Exempt payees should complete a substitute Form W-9 to avoid possible erroneous backup withholding. Furnish your taxpayer identification number, check the appropriate box for your status, check the "Exempt from backup withholding" box, sign and date the form and return it to the payer. Foreign payees who are not subject to backup withholding should complete an appropriate Form W-8 and return it to the payer.

Privacy Act Notice.    Section 6109 requires you to provide your correct taxpayer identification number to payers who must file information returns with the IRS to report interest, dividends, and certain other income paid to you to the IRS. The IRS uses the numbers for identification purposes and to help verify the accuracy of your return and may also provide this information to various government agencies for tax enforcement or litigation purposes and to cities, states, and the District of Columbia to carry out their tax laws, and may also disclose this information to other countries under a tax treaty, or to Federal and state agencies to enforce Federal nontax criminal laws and to combat terrorism. Payers must be given the numbers whether or not recipients are required to file tax returns. Payers must generally withhold 28% of taxable interest, dividend, and certain other payments to a payee who does not furnish a taxpayer identification number to a payer. Certain penalties may also apply.

Penalties

(1)

Failure to Furnish Taxpayer Identification Number. If you fail to furnish your correct taxpayer identification number to a payer, you are subject to a penalty of $50 for each such failure unless your failure is due to reasonable cause and not to willful neglect.

(2)

Civil Penalty for False Information with Respect to Withholding. If you make a false statement with no reasonable basis that results in no backup withholding, you are subject to a $500 penalty.

(3)

Criminal Penalty for Falsifying Information. Willfully falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE INTERNAL REVENUE SERVICE.

QuickLinks

GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9
GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 Page 2

EX-99.(A)(5)(B)

Exhibit (a)(5)(B)

This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below). The Offer (as defined below) is made solely by the Offer to Purchase, dated May 23, 2005, and the related Letter of Transmittal, and any amendments thereto, and is being made to all holders of Shares. Purchaser (as defined below) is not aware of any state where the making of the Offer is prohibited by administrative or judicial action pursuant to any valid state statute. If Purchaser becomes aware of any valid state statute prohibiting the making of the Offer, Purchaser will make a good faith effort to comply with such statute. If, after such good faith effort, Purchaser cannot comply with such state statute, the Offer will not be made to nor will tenders be accepted from or on behalf of the holders of Shares in such state.

Notice of Offer to Purchase for Cash

Any and All Outstanding Shares of Common Stock

of

Eon Labs, Inc.

at

$31.00 Net Per Share in Cash

by

Zodnas Acquisition Corp.

an indirect wholly owned subsidiary of

Novartis AG

Zodnas Acquisition Corp. (“Purchaser”), a Delaware corporation and an indirect wholly owned subsidiary of Novartis Corporation (“Novartis US”), a New York corporation and an indirect wholly owned subsidiary of Novartis AG, a Swiss corporation, hereby offers to purchase any and all outstanding shares of common stock, par value $0.01 per share (the “Shares”), of Eon Labs, Inc. (the “Company”) for $31.00 per Share, net to the seller in cash, without interest (the “Offer Price”), upon the terms and subject to the conditions set forth in the Offer to Purchase dated May 23, 2005 (the “Offer to Purchase”), and in the related Letter of Transmittal (which, as each may be amended from time to time, together constitute the “Offer”). Tendering stockholders who have Shares registered in their names and who tender directly to ComputerShare Trust Company, Inc. (the “Depositary”) will not be charged brokerage fees or commissions or, subject to Instruction 6 of the Letter of Transmittal, transfer taxes on the purchase of Shares pursuant to the Offer. Stockholders who hold their Shares through a broker or bank should consult such institution as to whether it charges any such fees or commissions. Novartis US or Purchaser will pay all charges and expenses of the Depositary, Georgeson Shareholder Communications Inc., which is acting as Information Agent for the Offer (the “Information Agent”), and Goldman, Sachs & Co., which is acting as Dealer Manager for the Offer (the “Dealer Manager”), incurred in connection with the Offer.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON JUNE 20, 2005, UNLESS THE OFFER IS EXTENDED.

The Offer is conditioned upon (1) the contemporaneous or immediately subsequent purchase by Novartis US or its designees of the 60,000,000 Shares owned by Santo Holding (Deutschland) GmbH (“Santo”), representing approximately 67.5% of the outstanding equity interest in the Company, pursuant to the Agreement for Purchase and Sale of Stock, dated as of February 20, 2005, by and among Novartis US, Santo and, for purposes of Section 12 thereof only, Novartis AG (the “Santo Agreement,” and such stock purchase, the “Santo Purchase”); and (2) satisfaction of all applicable legal requirements for consummating the Offer (the “Tender Offer Conditions”). Although there are no conditions to the Offer other than those described above, because the Offer is conditioned upon the Santo Purchase, each of the conditions to the consummation of the Santo Purchase, including consummation of the transactions contemplated by the Hexal Agreement (described below), is indirectly a condition to the Offer.

Purchaser is making the Offer pursuant to the Agreement and Plan of Merger, dated as of February 20, 2005, by and among Novartis US, Purchaser, the Company and, for purposes of Section 10.12 thereof only, Novartis AG (the “Merger Agreement”). Pursuant to the Santo Agreement, Santo has agreed to sell, and Novartis US has agreed to acquire, all 60,000,000 Shares owned by Santo (the “Santo Shares”) for €1,300,000,000, plus interest from January 1, 2005 through the closing under the Santo Agreement at an annualized rate of 1% above the three-month Euro Interbank Offering Rate (EURIBOR). Pursuant to the Share and Partnership Interest Sale and Transfer Agreement (the “Hexal Agreement”), by and among Novartis (Deutschland) GmbH (“Novartis Deutschland”), Novartis AG (as guarantor) and certain members of the Strüngmann family, dated as of February 16-17, 2005, relating to the acquisition of shares in A+T Vermögensverwaltung GmbH as well as partnership interests in A+T Holding GmbH & Co. KG, Novartis Deutschland will acquire 137,122 Shares currently owned by Hexal AG ("Hexal"), a wholly owned subsidiary of A+T Vermögensverwaltung GmbH, which represents approximately 0.2% of the outstanding shares of Common Stock. Although Purchaser is offering to acquire any and all Shares, the Shares currently owned by Santo and Hexal will not be tendered into the Offer. Therefore, Purchaser is effectively offering pursuant to the Offer to acquire any and all Shares not owned by Santo or Hexal (all Shares other than the Santo Shares, the “Public Shares”).

                Following the consummation of the Offer and the satisfaction or waiver of certain conditions, if a majority of the Public Shares are tendered in the Offer, Novartis US is obligated to cause a merger between Purchaser and the Company, with the Company continuing as the surviving corporation (the “Merger”). If following consummation of the Offer, Purchaser and Novartis US own at least 90% of the Shares, the parties to the Merger Agreement will cause the Merger to occur without a vote of the Company’s stockholders pursuant to Section 253 of the Delaware General Corporation Law (“DGCL”). In the Merger, each outstanding Share that is not owned by the Company directly as treasury stock or by Novartis AG or any of its subsidiaries (other than in a representative or fiduciary capacity), and other than Shares held by Company stockholders that perfect their appraisal rights under the DGCL, will be cancelled and automatically converted into the right to receive the Offer Price in cash, without interest.

                If less than a majority of the Public Shares are tendered in the Offer (inclusive of any Shares tendered during any subsequent offering period, if one is offered), until the earlier of February 11, 2006 or until Novartis US and its subsidiaries own 90% of the Shares, Purchaser and Novartis US will not be permitted to effect a merger between Purchaser and the Company without the approval of a majority of the then-outstanding Public Shares. Following the Offer, Purchaser may buy Shares in the market or make another tender offer.

                Both the Company’s Board of Directors (the “Company Board”) and a special committee of the Company Board consisting of independent directors not affiliated with Santo (the “Special Committee”) have (i) determined by unanimous vote that each of the transactions contemplated by the Merger Agreement, including the Offer and the Merger, is fair to and in the best interests of the Company and its stockholders other than Santo, (ii) approved the Santo Purchase, the Offer, the Merger and the Merger Agreement in accordance with the DGCL, (iii) recommended acceptance and approval of the Offer and adoption of the Merger Agreement by the Company’s stockholders and (iv) taken all other action within the Company Board’s and the Special Committee’s power to render Section 203 of the DGCL, if applicable, inapplicable to the Santo Purchase, the Offer and the Merger.

Subject to the Merger Agreement and applicable rules and regulations, if any Tender Offer Condition is not satisfied, Purchaser and Novartis US may: (a) terminate the Offer and return all tendered Shares; (b) extend the Offer and, subject to certain conditions and to withdrawal rights as set forth in Section 5 of the Offer to Purchase, retain all Shares until the Expiration Date (as defined below) of the Offer as so extended; or (c) waive the unsatisfied condition (to the extent legally permissible) and accept for payment all Shares so tendered. Purchaser and Novartis US expressly reserve the right to waive (to the extent legally permissible) any of the conditions to the Offer. Purchaser and Novartis US may not, without the prior written consent of the Company by action of the Special Committee, decrease the Offer Price or change the form of consideration, decrease the number of Public Shares sought to be purchased in the Offer, impose additional conditions to the Offer or amend any other term of the Offer in any manner adverse to the holders of Public Shares, except as may be provided in the Merger Agreement.

                For purposes of the Offer, Purchaser will be deemed to have accepted for payment (and thereby purchased) Shares validly tendered and not properly withdrawn if and when Purchaser gives oral or written notice to the Depositary of Purchaser’s acceptance for payment of such Shares pursuant to the Offer. Upon the terms and subject to the conditions of the Offer, payment for Shares accepted for payment pursuant to the Offer will be made by deposit of the purchase price therefor with the Depositary, which will act as agent for tendering stockholders for the purpose of receiving payments from Purchaser and transmitting such payments to stockholders whose Shares have been accepted for payment. Under no circumstances will interest on the purchase price for Shares tendered in the Offer be paid by Purchaser, regardless of any extension of the Offer or any delay in making such payment. In all cases, payment for Shares tendered and accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of (1) certificates representing such Shares, or timely confirmation of a book-entry transfer of such Shares into the Depositary’s account at the Book-Entry Transfer Facility (as defined in the Offer to Purchase) pursuant to the procedures set forth in Section 4 of the Offer to Purchase, (2) the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent’s Message (as defined in the Offer to Purchase) in connection with a book-entry transfer, and (3) any other documents required by the Letter of Transmittal.

                Under the Merger Agreement, Purchaser and Novartis US are required to extend the Expiration Date if at the scheduled Expiration Date (as defined below) any of the Tender Offer Conditions have not been satisfied or waived. Pursuant to the Merger Agreement, each such extension will not exceed the number of days that Purchaser or Novartis US reasonably believes is necessary to cause the Tender Offer Conditions to be satisfied and will not, in any event, exceed 30 Business Days unless the parties to the Merger Agreement (with action by the Company requiring the approval of the Special Committee) otherwise agree. In addition, Purchaser and Novartis US further reserve the right to extend the Offer for a period of time not to exceed ten Business Days (i) on one occasion in order to obtain the tender of a majority of the Public Shares, provided that at the time of extension at least 40% of the Public Shares have been tendered and not withdrawn, and (ii) on one occasion in order to obtain 90% of the total outstanding Shares, provided that at the time of extension the number of Public Shares that have been tendered and not withdrawn is sufficient, together with other Shares owned by us, or to be acquired under the Santo Agreement, to constitute at least 80% of the total outstanding Shares. “Business Day” means any day that is not a Saturday, a Sunday or other day on which Banks are required or authorized by Law to be closed in The City of New York. Purchaser and Novartis US also have the right to extend the Offer for any period required by applicable law.

                In accordance with Rule 14d-11 of the General Rules and Regulations under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), Purchaser and Novartis US may, subject to certain conditions, provide a subsequent offering period of between three and twenty business days (as such term is defined under Exchange Act Rule 14d-1(g)(3)) following the Expiration Date. If included, a subsequent offering period would be an additional period of time, following the expiration of the Offer and the purchase of Shares in the Offer, during which stockholders may tender any Shares not tendered in the Offer. A subsequent offering period, if one is included, is not an extension of the Offer, which already would have been completed.

                Any extension, delay, termination, waiver or amendment of the Offer will be followed as promptly as practicable by public announcement, in the case of an extension of the Offer to be made no later than 9:00 a.m., New York City time, on the next business day (as such term is defined under Exchange Act Rule 14d-1(g)(3)) after the previously scheduled Expiration Date, in accordance with the public announcement requirements of the Exchange Act Rule 14e-1(d). If the Expiration Date is extended, during such extension, all Shares previously tendered and not withdrawn will remain subject to the Offer and subject to withdrawal rights. Company stockholders may withdraw their Shares previously tendered at any time prior to the Expiration Date as it may be extended from time to time. “Expiration Date” means 12:00 Midnight, New York City time, on June 20, 2005 unless the period of time for which the initial offering period of the Offer is open is extended, in which case “Expiration Date” will mean the latest time and date on which the Offer, as so extended, will expire.

                Other than during a subsequent offering period, if one is provided, tendering shareholders may withdraw tenders of Shares made pursuant to the Offer at any time prior to the Expiration Date. Thereafter, such tenders are irrevocable, except that they may be withdrawn after July 21, 2005 unless such Shares have been accepted for payment as provided in this Offer to Purchase. If Novartis US and Purchaser extend the period of time during which the Offer is open, are delayed in accepting for payment or paying for Shares pursuant to the Offer for any reason or are unable to accept Shares for payment pursuant to the Offer for any reason, then, without prejudice to the rights of Novartis US and Purchaser under the Offer, the Depositary may, on Novartis US and Purchaser’s behalf, retain all Shares tendered, and such Shares may not be withdrawn except as otherwise provided in the Offer to Purchase.

                To withdraw tendered Shares, a written or facsimile transmission notice of withdrawal with respect to the Shares must be timely received by the Depositary at one of its addresses set forth on the back cover of the Offer to Purchase, and the notice of withdrawal must specify the name of the person who tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the registered holder of Shares, if different from that of the person who tendered such Shares. If the Shares to be withdrawn have been delivered to the Depositary, a signed notice of withdrawal with (except in the case of Shares tendered by an Eligible Institution) signatures guaranteed by an Eligible Institution must be submitted prior to the release of such Shares. In addition, such notice must specify, in the case of Shares tendered by delivery of certificates, the name of the registered holder (if different from that of the tendering stockholder) and the serial numbers shown on the particular certificates evidencing the Shares to be withdrawn or, in the case of Shares tendered by book-entry transfer, the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Shares. Withdrawals may not be rescinded, and Shares withdrawn will thereafter be deemed not validly tendered for purposes of the Offer. However, withdrawn Shares may be re-tendered by again following one of the procedures described in Section 4 of the Offer to Purchase, at any time prior to the Expiration Date. Novartis US and Purchaser will determine, in their sole discretion, all questions as to the form and validity (including time of receipt) of any notice of withdrawal, and their determination will be final and binding. None of Novartis AG, Novartis US, Purchaser, the Depositary, the Dealer Manager, the Information Agent or any other person will be under any duty to give notification of any defect or irregularity in any notice of withdrawal or waiver of any such defect or irregularity or incur any liability for failure to give any such notification.

                The information required to be disclosed by Exchange Act Rule 14d-6(d)(1) is contained in the Offer to Purchase and is incorporated herein by reference.

                The Company has provided Purchaser with the Company’s stockholder list and security position listing for the purpose of disseminating the Offer to holders of Shares. The Offer to Purchase and the related Letter of Transmittal and, if required, other relevant materials, will be mailed by Purchaser to record holders of Shares and furnished to brokers, dealers, commercial banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the stockholder list or, if applicable, who are listed as participants in a clearing agency’s security position listing, for subsequent transmittal to beneficial owners of Shares.

The Offer to Purchase and the related Letter of Transmittal contain important information which should be read carefully before any decision is made with respect to the Offer.

Any questions and requests for assistance may be directed to the Information Agent as set forth below. Requests for copies of the Offer to Purchase and the related Letter of Transmittal and all other tender offer materials may be directed to the Information Agent or the Dealer Manager at their respective addresses and telephone numbers set forth below and copies will be furnished promptly at Purchaser’s expense. Purchaser will not pay any fees or commissions to any broker or dealer or any other person (other than the Information Agent, the Dealer Manager and the Depositary) for soliciting tenders of Shares pursuant to the Offer.

The Information Agent for the Offer is:

17 State Street, 10th Floor

New York, New York 10004

Stockholders Call Toll Free: (877) 278-4774

Banks and Brokerage Firms Call: (212) 440-9800

The Dealer Manager for the Offer is:

Goldman, Sachs & Co.

85 Broad Street

New York, New York 10004

Call Collect: (212) 902-1000

Call Toll Free: (800) 323-5678

May 23, 2005

EX-99.(A)(6)(A)

Exhibit (a)(6)(A)

EFiled: Feb 22 2005 11:34AM EST

Filing ID 5187912

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

		x
ELLEN WIEHL,		:
		:	C A. No.
	Plaintiff,	:
		:
vs.		:
		:
EON LABS, INC., NOVARTIS AG,		:
THOMAS STRUNGMANN, BERNHARD		:
HAMPL, MARK R. PATTERSON,		:
FRANK F. BEELITZ, and		:
DOUGLAS M. KARP,		:
		:
	Defendants.	:
		:
		x

CLASS ACTION COMPLAINT

Plaintiff, by her attorneys, alleges upon information and belief, except as to the allegations that pertain to plaintiff, which are alleged upon personal knowledge, as follows:

SUMMARY OF THE ACTION

1.This is a stockholders’ class action on behalf of the public stockholders of Eon Labs, Inc. common stock (“Eon” or the “Company”) to enjoin the proposed acquisition of the publicly owned shares of Eon’s common stock by Novartis AG (“Novartis”) as detailed herein (the “Proposed Transaction”)

PARTIES

2.Plaintiff Ellen Wiehl has been the owner of common stock of the Company since prior to the announcement of transaction herein complained of, and at all times continuously to date.

3.Eon is a corporation duly organized and existing under the laws of the State of Delaware with its principal place of business at 1999 Marcus Avenue, Lake Success, New York, 11042. Eon is one of the largest suppliers of generic pharmaceuticals manufacturers in the United States employing approximately 500 people. Eon produces a broad range of pharmaceuticals in a wide variety of therapeutic categories. In 2004, Eon reported record sales of $ 431 million, an increase of 31% from 2003.

4.Headquartered in Basel, Switzerland, Defendant Novartis is Europe’s fourth largest pharmaceutical company. In 2004, Novartis had achieved sales of $ 28.2 billion and a net income of $ 5.8 billion. Novartis companies employ about 81,400 people and operate in over 140 countries around the world. Novartis through its proposed purchase of privately owned Hexal AG will own approximately 67.7% of the equity of Eon.

5.Defendant Thomas Strungmann (“Strungmann”) is and was at all relevant times the Company’s Chairman of the Board.  Defendant Strungmann and his twin brother, Andreas Strungmann, also co-founded Hexal AG (“Hexal”), a German corporation founded in 1986 which manufactures and sells pharmaceutical products in Germany, and has served as its Co-Chief Executive Officer and Co-President since then. Hexal owns approximately 67.7% of Eon.

6.Defendant Bernhard Hampl (“Hampl”) is and was at all relevant times a director of the Company, as well as the Company’s President and Chief Executive Officer (“CEO”). From May 1995 to October 1995, Dr. Hampl was employed by Hexal to evaluate the possibility of establishing a U.S. subsidiary.

7.Defendants Mark R. Patterson (“Patterson”), Frank F. Beelitz (“Beelitz”), and Douglas M. Karp (“Karp”) are and were at all relevant times a directors of the Company.

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8.The defendants named in paragraphs 5 through 7, collectively referred to as the “Individual Defendants,” as officers and/or directors of the Company, are in a fiduciary relationship with plaintiff and the other public shareholders of Eon, and owe them the highest obligations of good faith and fair dealing.

9.Defendant Novartis, through its proposed acquisition of Hexal will have a 67.7% ownership interest in Eon. As the Company’s controlling stockholder, Novartis will be in a fiduciary relationship with plaintiff and the other public shareholders of Eon and as such will owe them the highest fiduciary duties of good faith, fair dealing, and full and candid disclosure.

CLASS ACTION ALLEGATIONS

10.Plaintiff brings this action pursuant to Court of Chancery Rule 23, individually and as a class action on behalf of all other stockholders of the Company (except defendants herein and any persons, firm, trust, corporation, or other entity related to or affiliated with them and their successors in interest), who are or will be threatened with injury arising from defendants’ wrongful actions, as more fully described herein (the “Class”).

11.This action is properly maintainable as a class action for the following reasons:

(a)The Class is so numerous that joinder of all members is impracticable. As of November 8, 2004, there were 88,823,124 shares of the Company’s stock outstanding. There are likely hundreds, if not thousands, of record and beneficial holders of Eon common stock.

(b)There are questions of law and fact which are common to the Class, including, inter alia, the following:

(i)whether defendants have breached their fiduciary duties of undivided loyalty and good faith and fair dealing with respect to plaintiff and the other members of the Class in connection with the transaction;

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(ii)whether the Individual Defendants and Novartis, in connection with the transaction, are pursuing a course of conduct designed to eliminate the public shareholders of Eon in violation of their fiduciary obligations;

(iii)whether Eon’s directors are able to negotiate at arm’s length and in good faith on behalf of Eon’s minority public shareholders;

(iv)whether Novartis, as the controlling shareholder of Eon, has breached and is breaching its fiduciary duties to the Eon shareholders by making an unfair and inadequate offer to take the Company private;

(v)whether defendants have breached any of their other fiduciary duties to plaintiff and the other members of the Class in connection with the transaction, including the duties of candor, good faith, honesty and fair dealing; and

(vi)whether plaintiff and the other members of the Class would suffer irreparable injury were the transaction complained of herein consummated.

(c)Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff’s claims are typical of the claims of the other members of the Class and the Plaintiff has the same interests as the other members of the Class.  Accordingly, Plaintiff is an adequate representative of the Class and will fairly and adequately protect the interests of the Class.

(d)The prosecution of separate actions by individual members of the Class would create the risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the Class which would as a practical matter be dispositive of the

4

interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interests.

(e)Defendants have acted, or refused to act, on grounds generally applicable to, and causing injury to, the Class and, therefore, preliminary and final injunctive relief on behalf of the Class as a whole is entirely appropriate.

BACKGROUND

12.Headquartered in Holzkirchen, Germany, Hexal is a privately-held pharmaceutical company which develops, produces, markets and distributes modern generic drugs and medicinal products. Hexal was founded in 1986 by Strungman and his twin brother Andreas Strungmann. Hexal ranks as the second largest manufacturer in the German generics market and the fourth largest generic manufacturer worldwide, employing approximately 7,000 people in over 40 countries. Hexal achieved sales of $ 1.65 billion in 2004.

13.In 1995, Hexal bought 50% of the publicly traded shares of Eon. Over time Hexal has increased its stake. Presently, defendant Strungmann and his twin brother Andreas and their families hold a 67.7% stake in Eon Labs through a holding company.(1)

14.Hexal, controlled by Defendant Strungman, does significant business with Eon. In 2003, the Company had net sales of $0.9 million of products to subsidiaries of Hexal. The Company purchased products and supplies from Hexal and its subsidiaries in the aggregate of $1.0 million in

(1)The holding company, Santo Holding (Deutschland) AG, (“Santo”) is a privately held entity that owns 60,000,000 shares of Eon common stock, representing approximately 67.6% of the company’s outstanding common stock. Defendant Strüngmann, the Chairman of the Company’s Board of Directors and the Co-Chief Executive Officer and Co-President of Hexal AG, is an indirect significant stockholder and director of Santo. Defendant Strüngmann is an indirect significant stockholder and member of the board of directors of Hexal AG, a privately held entity, which owns 137,122 shares of common stock, representing ownership of approximately 0.15% of the Company’s outstanding common stock.  As a result, Defendant Dr. Strüngmann is the beneficial owner of 60,137,122 shares of common stock, representing ownership of approximately 67.8% of the Company’s outstanding common stock.

5

2003. The Company has an agreement with Hexal regarding the drug Cyclosporine. Pursuant to that agreement, the Company has been granted an exclusive and perpetual license to use patented technology from Hexal and pay Hexal a royalty on its sales of Cyclosporine, which was developed using that licensed technology. Pursuant to that agreement’s royalty arrangement, the Company expensed $3.2 million in 2003. In March 2003, the Company memorialized its agreement with Hexal regarding the sale of Cyclosporine products to a third party. Pursuant to that agreement the Company has been granted an exclusive license to use patented technology from Hexal to sell Cyclosporine to the third party outside of the United States. The Company makes royalty payments to Hexal on such sales as described above. The Company also sells the active pharmaceutical ingredient cyclosporine to the third party and retains an administrative fee from such sales, forwarding the remainder to Hexal. Pursuant to this agreement, the Company was obligated to forward $2.7 million to Hexal in connection with such sales made in 2003. In March 2002, the Company entered into a five-year technology agreement with Hexal. Pursuant to that agreement, Hexal cooperates with the Company with respect to the development, manufacture and sale in the United States of, and the sharing of certain information relating to, certain generic pharmaceutical products that Hexal develops. The Company has entered into several underlying product agreements for the rights to several products. The Company expensed $1.3 million in 2003 as provided in the underlying agreements. During 2003, Hexal incurred certain miscellaneous expenses on behalf of the Company totaling $0.1 million, which was reimbursed by the Company.

15.On February 21, 2005, in an attempt to boost its own lagging generic drug business, Novartis announced that it had entered into a definitive merger agreement to acquire 100% of Hexal and Hexal’s 67.7% stake (65.4% fully diluted) in Eon for a total of EUR 5.65 billion in cash or approximately $8.3 billion.

6

16.In addition, Novartis will launch a tender offer to acquire the remaining 31.9 million fully diluted shares (34.6%) in Eon Labs for $ 31.00 per share.

17.To facilitate the acquisition of Hexal and control of Eon Labs, Novartis will undertake a series of transactions. Initially, two separate definitive agreements to pay a total of EUR 5.65 (or approximately $ 7.4 billion) billion in cash to acquire 100% of privately-held Hexal, and to acquire 60 million shares of Eon Labs (67.7% of Eon Labs’s share capital and 65.4% on a fully-diluted basis) from Santo.

18.The second step involves a definitive agreement by which Novartis will offer to acquire the remaining approximately 31.9 million fully diluted public shares (treasury method) of Eon for $ 31.00 per share in cash.

19.The transaction has been interpreted as a means to boost sales at Novartis’ Sandoz Generic drug unit, Novartis’ slowest growing division in 2004. For example, Dieter Winet, a portfolio manager at Swisscanto Asset Management has stated “The generics area was a problem for Novartis and with this acquisition they have resolved that problem with a quantum leap.”

20.Both Eon and Hexal will be merged with Novartis’ Sandoz Unit, creating the world’s largest maker of generic pharmaceuticals and medicines based on global revenues. The combined company, which will operate under the Sandoz name will have a combined pro forma 2004 sales of approximately $5.1 billion and a portfolio of more than 600 drugs.

21.Following the consummation of the transaction, Defendant Hampl will serve as Sandoz’s CEO.

22.Contrary to the Company’s portrayal, the transaction actually represents a substantial discount to Eon’s minority public shareholders based on the intrinsic value of the Company and its

7

future growth outlook, and is designed to take advantage of Eon’s current trading price without payment of any reasonable premium for the actual value of its assets or its future business prospects.

23.According to estimates, Novartis is paying about 3.8 times Hexal’s and Eon’s combined sales. By comparison, in a similar transaction by Teva Pharmaceuticals (“Teva”) in January 2004, Teva paid approximately 6 times revenue in its purchase of Sicor Inc.

24.Defendant Novartis’ tender offer for the minority shares of Eon is only approximately 11 percent more than Friday’s closing price of Eon shares.

25.Accordingly, the consideration in the transaction is not an industry standard premium at all, nor is it in the best interests of Eon’s minority public stockholders. To the contrary, the consideration in the transaction is woefully inadequate, unfair, and clearly does not represent the true value of the Company.

26.Novartis is intent on paying the lowest possible price to Class members, even though the Individual Defendants and Novartis, as the majority shareholder of Eon, are duty-bound to maximize shareholder value.

27.Novartis has timed the transaction to freeze out Eon’s minority shareholders in order to capture for itself  Eon’s future potential without paying an adequate or fair price to the Company’s minority shareholders, to place an artificial lid on the market price of Eon stock so that the market would not reflect the Company’s potential, thereby purporting to justify an unreasonably low price.  In fact Novartis notes in the merger announcement on February 21, 2005, that:

Over the past three years alone, Eon Labs has produced 15 first-to-market launches and has positioned itself as the market share leader for nearly half of the products in its portfolio, which includes 67 molecules in 147 dosage strengths.  Eon Labs currently has 27 ANDAs (Abbreviated New Drug Applications) pending before the US Food and Drug Administration (FDA) covering approximately USD 14.3 billion in annual branded prescription drug sales.  The combined pipeline covers nearly all of the major

8

molecules predicted to lose patent protection during the next few years, representing an estimated USD 69 billion in US product sales between 2005 and 2009.

28.As noted above, Eon has seen remarkable growth in recent years, which has continued into the present fiscal year, which is not properly valued in the Proposed Transaction. For example, Eon on Oct. 21, 2004 Eon reported net income of $28.1 million for the third quarter ended September 30, 2004, compared to $17.8 million in the comparable quarter in 2003, an increase of 57.6%.  For the nine months ended September 30, 2004, net income was $89.2 million, compared to $51.0 million in the comparable period in 2003, an increase of 75.0%.  On July 22, 2004, Eon reported net income of $28.8 million for the second quarter ended June 30, 2004, compared to $18.0 million in the comparable quarter in 2003, an increase of 59.6%.  For the six months ended June 30, 2004, net income was $61.1 million, compared to $33.1 million in the comparable period in 2003, an increase of 84.4%. Moreover, on April 22, 2004, Eon reported record net income of $32.3 million for the first quarter ended March 31, 2004, compared to $15.1 million in the comparable quarter in 2003, an increase of 113.9%.

29.Furthermore, in conjunction with the merger announcement on February 21, 2005, Eon announced preliminary financial results for the fourth quarter and year end December 31, 2004 of approximately $30.2 million (net income) for the fourth quarter ended December 31, 2004. This represents an increase of 57.3% compared to the comparable quarter in 2003 of approximately $19.2 million. Diluted earnings per share if expected to be $0.33 for the forth quarter ended December 31, 2004, compared to $0.21 for the comparable quarter in 2003, representing an increase of 57.1%.  Moreover, Eon expects net income for the year ended December 31, 2004 to be $119.4 million, compared to $70.1 million in the comparable period in 2003, an increase of 70.2%.

9

30.In contrast, Novartis’ net income in the fourth quarter rose 1%, the slowest profit growth for Novartis in five quarters.

31.The consideration to be paid to Class members in the transaction is unfair and grossly inadequate because, among other things, the intrinsic value of Eon’s common stock is materially in excess of the amount offered for those securities in the proposed acquisition given the stock’s current trading price and the Company’s prospects for future growth and earnings.

32.Novartis timed its offer to take advantage of the decline in the market price of Eon’s stock.  The offer has the effect of capping the market for Eon’s stock to facilitate Novartis’ plan to obtain the public interest in Eon as cheaply as possible.

33.Under the circumstances, the Individual Defendants are obligated to explore all alternatives to maximize shareholder value.

34.The defendants have breached their duty of loyalty to Eon stockholders by using their control of Eon to force plaintiff and the Class to sell their equity interest in Eon at an unfair price, and deprive Eon’s public shareholders of maximum value to which they are entitled. The Individual Defendants have also breached the duties of loyalty and due care by not taking adequate measures to ensure that the interests of Eon’s public shareholders are properly protected from overreaching. Eon has breached its fiduciary duties, which arise from its control of Eon, by using its control for its own benefit.

35.The terms of the transaction are grossly unfair to the Class, and the unfairness is compounded by the gross disparity between the knowledge and information possessed by defendants by virtue of their positions of control of Eon and that possessed by Eon’s public shareholders. Defendants’ scheme and intent is to take advantage of this disparity and to induce the Class to

10

relinquish their shares in the acquisition at an unfair price on the basis of incomplete or inadequate information.

36.Unless enjoined by this Court, the defendants will continue to breach their fiduciary duties owed to plaintiff and the Class and will consummate the Proposed Transaction to the irreparable harm of plaintiff and the Class.

37.Plaintiff and the other members of the Class have no adequate remedy at law.

PRAYER FOR RELIEF

WHEREFORE, plaintiff demands judgment and preliminary and permanent relief, including injunctive relief, in her favor and in favor of the Class and against defendants as follows:

A.Declaring that this action is properly maintainable as a class action;

B.Enjoining defendants, their agents, counsel, employees and all persons acting in concert with them from consummating the Proposed Acquisition;

C.To the extent the Proposed Acquisition is consummated, rescinding it or awarding rescissory damages to the Class;

D.Directing defendants to account to the plaintiff and the Class for all damages suffered by them as a result of defendants’ wrongful conduct;

E.Awarding plaintiff the costs and disbursements of this action, including reasonable attorneys’ and experts’ fees; and

11

F.Granting such other and further relief as this Court may deem just and proper.

Dated: February 22, 2005

ROSENTHAL, MONHAIT, GROSS & GODDESS, P.A.
By:	/s/ Carmella P. Keener
Carmella P. Keener (DSBA No. 2810) 919 North Market Street, Suite 1401 P.O. Box 1070 Wilmington, Delaware 19899 (302) 656-4433
Attorneys for Plaintiff

OF COUNSEL:

FARUQI & FARUQI, LLP

320 East 39th Street

New York, New York 10016

(212) 983-9330

12

EX-99.(A)(6)(B)

Exhibit (a)(6)(B)

EFiled: Feb 22 2005 11:43AM EST

Filing ID 5187976

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

		x
		:
PAULENA PARTNERS LLC on behalf of
itself and all others similarly situated,		:
	Plaintiff,	:	C.A. No.
		:
	v.
		:
EON LABS INC., THOMAS STRUNGMANN,		:
BERNHARD HAMPL, MARK R. PATTERSON,
FRANK F. BEELITZ, DOUGLAS M. KARP,		:
NOVARTIS A/G, NOVARTIS CORPORATION
and ZODNAS ACQUISITION CORPORATION		:
	Defendants.	:
		x

CLASS ACTION COMPLAINT

Plaintiff, as and for its class action complaint, alleges upon personal knowledge as to itself and its own acts, and upon information and belief as to all other matters, as follows:

NATURE OF THE ACTION

1.This is a stockholder class action brought by plaintiff on behalf of the public shareholders of Eon Labs, Inc. (“Eon” or the “Company”) common stock against the Company and its directors and others to enjoin defendants from causing the Company to be acquired by Novartis A/G (“Novartis”), Novartis Corporation (“Novartis US”) and Zodnas Acquisition Group (“Zodnas” or “MergerSub”) at an inadequate consideration.

PARTIES

2.Plaintiff Paulena Partners, LLC has been the beneficial owner of the Company common stock at all relevant times and continues to be the beneficial owner of such shares.

3.Eon is a Delaware corporation with its principal place of business at 227-15 North Conduit Avenue, Laurelton, New York, 11413.  The Company is a generic pharmaceutical company engaged in developing, licensing, manufacturing, selling and distributing a broad range of prescription pharmaceutical products primarily in the United States.  For the year ended December 31, 2003, the Company generated sales and operating income of approximately $329.5 million and $115.3 million, respectively, and had total assets of approximately $441.5 million.

4.Defendant Thomas Strüngmann, Ph.D. (Strüngmann) has served as the Company’s Chairman of the Board since September 1995.  In addition, Dr. Strüngmann co-founded Hexal AG in 1986 and has served as its Co-Chief Executive Officer and Co-President since then.

5.Defendant Bernhard Hampl, Ph.D. (Hampl) has served as the Company’s Chief Executive Officer since October 1995 and a Director since September 1995.  In January 1996, Dr. Hampl became the Company’s President. From May 1995 to October 1995, Dr. Hampl was employed by Hexal AG to evaluate the possibility of establishing a U.S. subsidiary.

6.Defendant Mark R. Patterson (Patterson) has served as a Director of the Company since October 2002.

2

7.Defendant Frank F. Beelitz (Beelitz) has served as a Director of the Company since February 2002.

8.Defendant Douglas M. Karp (Karp) has been a Director since October 2002.

9.Defendant Novartis, headquartered in Basel, Switzerland, was created in 1996 from the merger of the Swiss companies, Ciba-Geigy and Sandoz.  Novartis is a world leader in the research and development of products to protect and improve health and well-being.  Its core businesses are in pharmaceuticals, consumer health, generics, eye-care, and animal health. In 2003, Novartis’s businesses achieved sales of USD 24.9 billion and a net income of USD 5.0 billion.

10.Defendant Novartis US is the North American headquarters of Novartis with its principal place of business located at 608 5th Ave. New York, New York 10020.

11.Defendant Zodnas is a Delaware corporation and an indirect wholly owned subsidiary of Novartis US.

12.The defendants identified in paragraphs 4 through 8 collectively constitute the entirety of The Company’s board of directors. These 5 individuals are hereinafter referred to collectively as the “Individual Defendants.”

13.As of April 27, 2004, defendant Strungmann, through Santo Holding GmbH (“Santo”), a German company, owned approximately 67.7% of Eon’s outstanding common stock and is therefore Eon’s majority stockholder.

14.The Individual Defendants, by virtue of their positions as officers and/or directors of the Company, and/or as the Company’s majority stockholder, stand in a

3

fiduciary relationship to the Company’s public stockholders and owe them the highest duties of good faith, fair dealing, due care, loyalty, and full and fair disclosures.

CLASS ACTION ALLEGATIONS

15.Plaintiff, a shareholder of the Company, brings this action as a class action pursuant to Delaware Rule of Chancery 23 on behalf of itself and all public common stock holders of the Company. Excluded from the Class are defendants, members of the immediate families of the defendants, their heirs and assigns, and those in privity with them.

16.The members of the Class are so numerous that joinder of all of them would be impracticable.  As of November 8, 2004 the Company had over 88 million shares of common stock outstanding.

17.Plaintiff’s claims are typical of the claims of the Class, since plaintiff and the other members of the Class have and will sustain damages arising out of defendants’ breaches of their fiduciary duties. Plaintiff does not have any interests that are adverse or antagonistic to those of the Class.  Plaintiff will fairly and adequately protect the interests of the Class.  Plaintiff is committed to the vigorous prosecution of this action and has retained counsel competent and experienced in this type of litigation.

18.There are questions of law and fact common to the members of the Class including, inter alia, whether:

(a)the defendants have and are breaching their fiduciary duties to the detriment of the Company’s shareholders;

(b)the Class has been damaged and the extent to which members of the Class have sustained damages, and what is the proper measure of those damages.

4

19.The prosecution of separate actions by individual members of the Class would create the risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the Class which would as a practical matter be dispositive of the interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interests.

20.Defendants have acted, or refused to act, on grounds generally applicable to, and causing injury to, the Class and, therefore, preliminary and final injunctive relief on behalf of the Class as a whole is appropriate.

SUBSTANTIVE ALLEGATIONS

21.On February 20, 2005, Eon, Novartis US, Zodnas and Novartis entered into an Agreement (the “Santo Agreement”) pursuant to which Novartis US agreed to purchase, and Santo agreed to sell, all of the 60 million shares of common stock (the “Santo Shares”) of the Company owned by Santo, representing approximately 67.5% of the outstanding shares of Company common stock. Under the terms of the Agreement, Zodnas will commence a tender offer (the “Offer”) for all of the outstanding shares of Company Common Stock other than the Santo Shares, at a price equal to $31.00 per share. The Offer is not conditioned upon any minimum number of shares being lendered, but is contingent upon the contemporaneous (or immediately subsequent) closing of the Santo Agreement.  The closing of the Santo Agreement is further conditioned on the closing another agreement that Novartis AG entered into with Hexal AG (“Hexal”), a German company controlled by Defendant Strüngmann.

5

22.Following the completion of the Offer and the purchase of the Santo Shares, if a majority of the public shares are purchased in the Offer, any remaining shares of Company Common Stock will be acquired by Novartis US in a merger (the “Merger”) in which such remaining public shares will be converted into the right to receive $31.00 per share in cash.

23.Following the consummation of the Offer, Defendant Hampl will serve as Chief Executive Officer of Sandoz U.S., Novartis’ United States generic pharmaceutical business

24.This offer arrives on the heels of the Company’s announcement that it expected fourth-quarter 2004 net profit of $30.2 million, up 57.3 percent from the year-earlier period, and that diluted earnings per share were expected to be 33 cents compared with 21 cents in the year-earlier quarter.

25.Recognizing the Company’s strong performance and potential for even greater growth, Novartis, Novartis US, Strungman and Hampl have determined to deny the Company’s public shareholders the opportunity to obtain fair value for their equity interest by proposing a transaction at an inadequate premium, thereby denying the Company’s public shareholders the opportunity to obtain fair value for their equity interest.

26.The consideration of $31.00 each per share to be paid to Class members is unfair and inadequate consideration because, among other things: (1) the intrinsic value of the Company’s stock is materially in excess of $31.00 per share, giving due consideration to the Company’s prospects for growth and profitability in light of its business, earnings power, present and future; (b) the $31.00 each per share price is not

6

the result of arm’s length negotiations but was fixed arbitrarily by the Company’s majority shareholders to “cap” the market price of the Company and obtain its assets and businesses at the lowest possible price.

27.The Offer is an attempt by Novartis, Novartis US, Strungman and Hampl to aggrandize themselves at the expense of the Company’s public stockholders.  The proposed acquisition will, for inadequate consideration, deny plaintiff and the other members of the Class the opportunity to share proportionately in the future success of the Company and its valuable assets, while permitting the defendants to benefit wrongfully from the transaction.

28.Given Strüngmann’s stock ownership of the Company and its representation on the Board of Directors, it is able to dominate and control the other directors. Under the circumstances, none of the directors can be expected to protect the Company’s public shareholders in a transaction which benefits Strüngmann at the expense of the Company’s public shareholders.

29.Because of the stock ownership of the Company by Strüngmann, no third party, as a practical matter, can attempt any competing bid for the Company as the success of any such bid would require the consent and cooperation of Strüngmann.

30.Plaintiff and the other members of the Class will suffer irreparable injury unless defendants are enjoined from breaching their fiduciary duties to the Company’s public shareholders in a proposed transaction which will benefit Novartis, Novartis US, Strungman and Hampl at the expense of the public shareholders.

31.Plaintiff and other members of the class have no adequate remedy at law.

7

WHEREFORE, plaintiff demands judgment against defendants, jointly and severally, as follows:

(1)Certifying this action as a class action and plaintiff as the Class representative and plaintiff’s counsel as Class counsel;

(2)Enjoining the Santo Agreement and the Offer preliminarily and permanently;

(3)To the extent the Santo Agreement and the Offer are consummated prior to the entry of this Court’s final judgment, rescinding it or granting the Class rescissory damages;

(4)Awarding plaintiff and the Class compensation for all damages they sustain as a result of defendants’ unlawful contact;

(5)Directing that the defendants account to plaintiff and the other members of the Class for all profits and any special benefits obtained as a result of their unlawful conduct.

(6)Awarding plaintiff the costs and disbursements of this action, including a reasonable allowance of attorneys’ fees and expenses; and

8

(7)Granting such other relief as the Court may find just and proper.

Dated: February 22, 2005		ROSENTHAL, MONHAIT, GROSS & GODDESS, P.A.
	By:	/s/ Carmella P. Keener
		Carmella P. Keener (DSBA No. 2810) 919 Market Street, Suite 1401 P.O. Box 1070 Wilmington, Delaware 19899
		ATTORNEYS FOR PLAINTIFF

THE BRUALDI LAW FIRM

29 Broadway

Twenty Fourth Floor

New York, New York 10006

Telephone (212) 952-0602

Facsimile (212) 952-0608

OF COUNSEL

9

EX-99.(A)(6)(C)

Exhibit (a)(6)(C)

EFiled: Feb 22  2005 5:12PM EST

Filing ID 5196326

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

ROBERT KEMP, IRRA for the benefit of Robert			:
Kemp, on behalf of himself			:
and all others similarly situated,			:
			:
		Plaintiff,	:	C. A. No.
			:
	v.		:
			:
EON LABS, INC., THOMAS STRÜNGMANN,			:
BERNHARD HAMPL, MARK. R.			:
PATTERSON, FRANK F. BEELITZ, DOUGLAS M.			:
KARP, and NOVARTIS AG
			:
		Defendants.	:

CLASS ACTION COMPLAINT

Plaintiff alleges upon information and belief, except as to paragraph 2 hereof, which is alleged upon knowledge, as follows:

1.Plaintiff brings this action pursuant to Rule 23 of the Rules of the Court of Chancery on his own behalf and as a class action on behalf of all persons, other than defendants and those in privity with defendants, who own the common stock of Eon Labs, Inc. (“Eon” or the “Company”).

2.Plaintiff has been the owner of the common stock of Eon since prior to the transaction herein complained of and continuously to date.

3.Eon is a corporation duly organized and existing under the laws of the Stale of Delaware 227-15 North Conduit Avenue, Laurelton, NY 11413. Eon is a generic pharmaceutical company engaged in developing, licensing, manufacturing, selling and distributing a range of

prescription pharmaceutical products primarily in the United States. The Company focuses primarily on drugs in a broad range of solid oral dosage forms, utilizing both immediate and sustained release delivery, in tablet, multiple layer tablet, film-coated tablet and capsule forms. Eon Labs obtains new generic pharmaceutical products primarily through internal product development and from strategic licensing or co-development arrangements with Hexal AG, as well as with other complies. Eon is controlled by the Strungmann family who own approximately 68.1% of Eon’s common shares. The privately-held Hexal AG is wholly owned by the Strüngmanns, As of November 8, 2004, the Company had over 88 million shares of its common stock outstanding.

4.Defendant Thomas Strüngmann, Ph.D. (“Strüngmann”) has served as the Company’s Chairman of the Board since September 1995. Strüngmann co-founded Hexal AG in 1986 and has served as its Co-Chief Executive Officer and Co-President since then.

5.Defendant Bernhard Hampl, Ph.D. (“Hampl”) has served as the Company’s Chief Executive Officer since October 1995 and a Director since September 1995.  In January 1996, Hampl became the Company’s President, From May 1995 to October 1995, Hampl was employed by Hexal AG to evaluate the possibility of establishing a U.S. subsidiary.

6.Defendant Mark R. Patterson (“Patterson”) has been a Director since October 2002.

7.Defendant Frank F. Beelitz (“Beelitz”) has been a Director since February 2002.

8.Defendant Douglas M. Karp (“Karp”) has been a Director since October 2002.

9.The individual defendants constitute the Board of Directors of Eon and, by reason of their corporate directorships and executive positions, stand in a fiduciary position relative to the Company’s public shareholders. Their fiduciary duties, at all times relevant herein, required

2

them to exercise their best judgment, and to act in a prudent manner, and in the best interest of the Company’s minority shareholders. Said defendants owe the public shareholders of Eon the highest duty of good faith, fair dealing, due care, loyalty, and full candid and adequate disclosure.

10.Defendant Novartis Corporation (“Novartis”), based in Basel, Switzerland, is a global pharmaceutical company.

CLASS ACTION ALLEGATIONS

11.Plaintiff brings this action on his own behalf and as a class action, pursuant to Rule 23 of the Rules of the Court of Chancery, on behalf of all security holders of the Company (except the defendants herein and any person, firm, trust, corporation, or other entity related to or affiliated with any of the defendants) or their successors in interest, who are or will be threatened with injury arising from defendants’ actions as more fully described herein.

12.This action is properly maintainable as a class action.

13.The class is so numerous that joinder of all members is impracticable. As of November 8, 2004, there were approximately 88 million shares of Eon common stock outstanding.

14.There are questions of law and fact which are common to the class including, inter alia, the following: (a) whether defendants have breached their fiduciary and other common law duties owed them to plaintiff and the members of the class; (b) whether defendants are pursuing a scheme and course of business designed to eliminate the public shareholders of Eon in violation of the laws of the State of Delaware in order to enrich Novartis at the expense and to the detriment of the plaintiff and the other public stockholders who are members of the class; (c) whether the proposed acquisition, hereinafter described, constitutes a breach of the duty of fair dealing with respect to the plaintiff and the other members of the class; and (d) whether the class is entitled to injunctive relief or damages as a result of defendants’ wrongful conduct.

3

15.Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. The claims of plaintiff are typical of the claims of the other members of the class and plaintiff has the same interests as the other members of the class. Plaintiff will fairly and adequately represent of the class.

16.The prosecution of separate actions by individual members of the class would create the risk of inconsistent or varying adjudications with respect to individual members of the class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the class which would as a practical matter be dispositive of the interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interests.

17.Defendants have acted in a manner which affects plaintiff and all members of the class, thereby making appropriate injunctive relief and/or corresponding declaratory relief with respect to the class as a whole.

CLAIM FOR RELIEF

18.On February 21, 2005, Novartis announced that it has agreed to pay $7.37 billion, in cash to buy 100% of Hexal AG of Germany and 68% of Eon Labs.  According to the release, Novartis will launch a tender offer to acquire for nearly $1 billion the remaining 31.9% of Eon that is publicly traded.

19.Novartis will undertake a series of transactions to acquire Hexal AG and control of Eon Labs. Novartis will buy Hexal and the two thirds of Eon that it does not already own for approximately $7.3 billion. In addition, Novartis has entered into a definitive agreement with the Company by which Novartis will offer to acquire the remaining approximately 31.9 million fully diluted shares of Eon $31.00 per share in cash. The agreement, which has been unanimously

4

approved by the Eon Labs Board of Directors and by a Special Committee consisting of directors not affiliated with the Strüngmanns, provides that an affiliate of Novartis will commence a tender offer and will, subject to legal requirements, purchase any and all shares tendered, but only iif the acquisition of the Strüngmann stake in Eon is consummated.

20.Accordingly, pursuant to the agreement, Novartis will own approximately 67.1% of Eon’s outstanding common shares.

21.The price of $31.00 per share to be paid to the class members is unfair and grossly inadequate consideration because, among other things: (a) the intrinsic value of the stock of Eon is materially in excess of $31.00 per share, giving due consideration to the possibilities of growth and profitability of Eon in light of its business, earnings and earnings power, present and future; (b) the $31.00 per share price is inadequate and offers an inadequate premium to the public stockholders of Eon; and (c) the $31.00 per share price is not the result of arm’s length negotiations but was fixed arbitrarily by Novartis to “cap” the market price of Eon stock, as part of a plan for defendants to obtain complete ownership of Eon assets and business at the lowest possible price.

22.The proposed transaction serves no legitimate business purpose of Eon but rather is an attempt by defendants to enable Novartis to benefit unfairly from the transaction at the expense of Eon’s public shareholders. The proposed plan will, for grossly inadequate consideration, deny plaintiff and the other members of the class their right to share proportionately in the future success of Eon and its valuable assets, while permitting Novartis to reap huge benefits from the transaction.

23.By reason of the foregoing acts, practices and course of conduct, Novartis has breached and will breach its duty as controlling stockholder of Eon by engaging in improper overreaching in attempting to carry out the proposed transaction on terms that are unfair to the Class.

5

24.By reason of the foregoing, the individual defendants have violated their fiduciary duties to Eon and the remaining stockholders of Eon in the event that they fail to oppose the transaction on the terms presently proposed.

25.Plaintiff and the class have suffered and will suffer irreparable injury unless defendants are enjoined from breaching their fiduciary duties and from carrying out the aforesaid plan and scheme.

26.Plaintiff and the other members of the class have no adequate remedy at law.

WHEREFORE, plaintiff demands judgment against the defendants jointly and severally, as follows:

A.declaring this action to be a class action and certifying plaintiff as a class representative;

B.enjoining, preliminarily and permanently, Novartis’s offer for acquisition of the Eon stock owned by plaintiff and the other members of the class under the terms presently proposed;

C.to the extent, if any, that the transaction or transactions complained of are consummated prior to the entry of this Court’s final judgment, rescinding such transaction or transactions, or granting, inter alia, rescissory damages;

D.directing that defendants account to plaintiff and the other members of the class for all damages caused to them and for all profits and any special benefits obtained by defendants as a result of their unlawful conduct;

E.awarding, the plaintiff the costs and disbursements of this action, including a reasonable allowance for the fees and expenses of plaintiff’s attorneys and experts; and

6

F.granting plaintiff and the other members of the class such other and further relief as may be just and proper.

ROSENTHAL, MONHAIT, GROSS & GODDESS, P.A.
By:	/s/ Carmella P. Keener
	Carmella P. Keener (DSBA No. 2810) 919 North Market Street, Suite 1401 P.O. Box 1070 Citizens Bank Center Wilmington, Delaware 19801 (302) 656-4433
	Attorneys for Plaintiff

OF COUNSEL:

BULL & LIFSHITZ, LLP
18 East 41^st Street
New York, NY10017

7

EX-99.(A)(6)(D)

Exhibit (a)(6)(D)

EFiled: Feb 23 2005 6:13 PM EST

Filing ID 5202529

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

	X
PETER J. CALCAGNO,	:
	:
Plaintiff,	:
	:	C. A. NO. 1125-N
vs.	:
	:
EON LABS, INC., NOVARTIS AG, THOMAS	:
STRUNGMANN, BERNHARD HAMPL, MARK R.	:
PATTERSON, FRANK F. BEELITZ, and	:
DOUGLAS M. KARP,	:
	:
Defendants.	X

SHAREHOLDER’S CLASS ACTION COMPLAINT

Plaintiff, through counsel, for his complaint against defendants, alleges upon personal knowledge with respect to paragraph 2 and upon information and belief based, inter alia, upon the investigation of counsel, as to all other allegations herein, as follows:

NATURE OF THE ACTION

1.This is a stockholder’s class action on behalf of the public stockholders of defendant Eon Labs, Inc. (“Eon” or the “Company”), against certain of its officers and directors and others to enjoin the proposed acquisition of the outstanding shares of Eon common stock by defendant Novartis AG (“Novartis”).  As set forth below, Novartis has entered into two definitive agreements, the first of which involves the acquisition of Hexal AG (“Hexal”), a privately owned German pharmaceutical company that holds approximately 67.7% of Eon through a subsidiary company, and the second of which is a merger agreement with Eon pursuant to which a wholly-owned subsidiary of Novartis will commence a cash tender offer to acquire all Eon shares not held by the Hexal subsidiary (the “Proposed Transaction”). Novartis then intends

to effect a merger to acquire all remaining Eon shares at the offer price of $31.00 per share (the “Merger”).

THE PARTIES

2.Plaintiff Peter J. Calcagno is and at all relevant times has been an owner of Eon common stock.

3.Defendant Eon is a Delaware corporation with its principal executive offices located at 227-15 North Conduit Ave., Laurelton NY 11413. Eon is one of the largest suppliers of generic pharmaceuticals in the United States. Eon produces a broad range of pharmaceuticals in a wide variety of therapeutic categories. Eon maintains a diverse product line consisting of more than 200 products representing various dosage strengths for over 60 drugs. As of November 8, 2004, Eon had over 88 million shares of common stock outstanding, held by hundreds if not thousands of shareholders of record. Eon common stock is listed and traded on NASDAQ NM under the ticker symbol ELAB.

4.Defendant Novartis is Europe’s fourth largest pharmaceutical company and is based in Basel, Switzerland. Novartis operates through 360 independent affiliates in 140 countries and offers its products and services through its Pharmaceutical and Consumer Health divisions. Upon its proposed acquisition of Hexal, Novartis will own approximately 67.7% of Eon. As such, Novartis will effectively control and dominate Eon’s affairs. Novartis, therefore, will be a controlling shareholder and owe fiduciary obligations of good faith, candor, loyalty and fair dealing to the public shareholders of Eon.

5.At all relevant times, defendants Thomas Strungmann (“Strungmann”), Bernhard Hampl (“Hampl”), Mark R. Patterson (“Patterson”), Frank F. Beelitz (“Beelitz”), and Douglas M. Karp (“Karp”) have served as the directors of Eon (collectively, the “Individual Defendants”).

2

6.In addition, at all relevant times, defendant Strungmann has served as Eon’s Chairman of the Board and defendant Hampl has served as Eon’s President and Chief Executive Officer. Furthermore, in 1986, defendant Strungmann co-founded Hexal with his twin brother and has served as Co-CEO and Co-President of Hexal since its inception. From May 1995 to October 1995, defendant Hempl was employed by Hexal to evaluate opportunities for Hexal to establish a U.S. subsidiary.

7.By virtue of their positions as directors and/or officers of Eon and/or their exercise of control and dominant ownership over the business and corporate affairs of Eon, each and every of the Individual Defendants and Novartis have, and at all relevant times had, the power to control and influence, and did control and influence and cause Eon to engage in the practices complained of herein. Each Individual Defendant and Novartis owed and owes Eon and its stockholders fiduciary obligations and were and are required to: use their ability to control and manage Eon in a fair, just and equitable manner; act in furtherance of the best interests of Eon and its stockholders; govern Eon in such a manner as to heed the expressed views of its public shareholders; refrain from abusing their positions of control; and not to favor their own interests at the expense of Eon and its stockholders.

8.As discussed in detail below, Novartis, in concert with the Individual Defendants, as well as the Individual Defendants, who together control the actions of Eon, have breached their fiduciary duties to Eon’s public stockholders by acting to cause or facilitate Novartis’ acquisition of the publicly-held minority shares of Eon for unfair and inadequate consideration, and colluding in Novartis’ coercive tactics in accompanying such buyout.

9.Each defendant herein is sued individually as a conspirator and aider and abettor, as well as in the case of the Individual Defendants, in their capacity as directors and/or officers

3

of Eon and the liability of each arises from the fact that they have engaged in all or part of the unlawful acts, plans, schemes, or transactions complained of herein.

CLASS ACTION ALLEGATIONS

10.Plaintiff brings this action pursuant to Rule 23 of the Rules of this Court, on behalf of itself and all other shareholders of the Company except the defendants herein and any persons, firm, trust, corporation, or other entity related to or affiliated with them and their successors in interest, who are or will be threatened with injury arising from defendants’ actions, as more fully described herein (the “Class”).

11.This action is properly maintainable as a class action for the following reasons:

(a)The Class is so numerous that joinder of all members is impracticable. There are millions of shares of Eon common stock which are outstanding, held by hundreds, if not thousands, of stockholders who are members of the Class.

(b)Members of the Class are scattered throughout the United States and are so numerous that it is impracticable to bring them all before this Court.

(c)There are questions of law and fact that are common to the Class and that predominate over any questions affecting individual class members. The common questions include, inter alia, the following:

(i)Whether defendants have engaged in and are continuing to engage in conduct which unfairly benefits Novartis at the expense of the members of the Class;

(ii)Whether the Individual Defendants, as officers and/or directors of the Company, and Novartis, the controlling stockholder of Eon are violating their fiduciary duties to plaintiff and the other members of the Class;

(iii)Whether plaintiff and the other members of the Class would be irreparably damaged were defendants not enjoined from the conduct described herein;

4

(iv)Whether defendants have initiated and/or timed their buyout of Eon shares to unfairly benefit Novartis at the expense of Eon’s public shareholders.

(d)The claims of plaintiff are typical of the claims of the other members of the Class in that all members of the Class will be damaged by defendants’ actions.

(e)Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff is an adequate representative of the Class.

(f)Plaintiff anticipates that there will not be any difficulty in the management of this litigation as a class action.

12.The class action is superior to any other method available for the fair and efficient adjudication of this controversy since it would be impractical and undesirable for each of the members of the Class who has suffered or will suffer damages to bring separate actions in various parts of the country.

SUBSTANTIVE ALLEGATIONS

13.On February 21, 2005, Novartis announced that it had entered into two definitive agreements. First, Novartis agreed to acquire 100% of Hexal, a privately-held company that held a 67.7% stake (65.4% fully diluted) in Eon through a subsidiary, namely Santo Holding (Deutschland) AG (“Santo”). Second, Novartis announced a definitive merger agreement with Eon pursuant to which an affiliate of Novartis will commence a tender offer to acquire all outstanding publicly held shares of Eon not held by Santo at a price of $31.00 per share in cash.

14.Also on February 21, 2005, Eon announced that its board of directors, and a purportedly independent special committee thereof (the “Special Committee”) had determined that the Proposed Transaction and Merger were fair to Eon’s public shareholders and recommended that the public shareholders accept the $31.00 per share tender offer.  Eon further

5

announced that both Hexal and Novartis would be merged into Novartis’ Sandoz unit, and that following the transactions defendant Hampl would become CEO of Sandoz U.S., Novartis’ generic pharmaceutical unit based in the United States.  It has also been reported that following the transactions Strungmann and his twin brother will take executive positions within Sandoz.

15.Both the Novartis and Eon press releases touted the outstanding recent financial performance of Eon. Novartis’ announcement noted that “over the past three years alone, Eon labs has produced 15 first-to-market launches and has positioned itself as the market share leader for nearly half of the products in its portfolio.” Eon released its preliminary financial results in the same news release announcing the Proposed Transaction and noted, among other things, that net income for the fourth quarter ended December 31, 2004 would increase by 57.3% while diluted earnings per share would increase by 57.1%. Eon also announced its expectation that net income for the year ended December 31, 2004 would increase by 70.2% and that “diluted earnings per share is expected to be a record $1.32 compared to $0.77 per share for the year 2003, an increase of 71.4%.” Eon also stated that “net sales were a record $431.0 million for the year ended December 31, 2004, compared to $329.5 million for the year 2003, an increase of 30.8%” and that “at December 31, 2004, Eon had $195.8 million of cash and short-term investments and no outstanding debt.”

16.In its press release of February 21, 2005, Novartis also noted that Eon “has a strategic partnership with Hexal AG” and that defendant Strungmann, along with his brother and their families “hold a 67.7% stake in Eon Labs through a holding company.” Given defendant Strungmann’s influence as an officer of Hexal and a director of Eon, the two companies do significant business together, including business related to the drug Cyclosporine, and have entered into various licensing and product agreements.

6

17.By virtue of its acquisition of Hexal, Novartis is a majority owner of Eon and is, therefore, well aware of the status of Eon’s development and success. In making its inadequate offer to acquire the remaining stock of Eon, Novartis has tried to take advantage of the fact that the market price of Eon stock does not fully reflect the progress and future value of the Company.

18.The value of $31.00 per share to be paid to the class members is unconscionable, unfair and grossly inadequate and constitutes unfair dealing because, among other things, (a) the Intrinsic value of the stock of Eon is materially in excess of the S31.00 value, giving due consideration to the possibilities of growth and profitability of Eon in light of its business, earnings and earnings power, present and future; (b) the $31.00 value is inadequate and offers only a 5.7% premium over Eon’s 52-week average to the public stockholders of Eon; and (c) the $31.00 value is not the result of arm’s-length negotiations, but was fixed arbitrarily by Novartis to “cap” the market price of Eon stock, as part of a plan for Novartis to obtain complete ownership of Eon at the lowest possible price. The intrinsic unfairness in defendants’ actions is also the product of the currently undervalued price of the shares in the marketplace.

19.Because Novartis is in possession of proprietary corporate information concerning Eon’s future financial prospects, the degree of knowledge and economic power between Novartis and the class members is unequal, making it grossly and inherently unfair for Novartis to obtain the remaining Eon shares at the unfair and inadequate price that it has proposed.

20.By offering grossly inadequate value for Eon’s shares and threatening or planning to use its coercive means of control to force the consummation of the transaction, Novartis is violating its duties as a majority shareholder.

21.Any buyout of Eon public shareholders by Novartis on the terms recently offered will deny class members their right to share proportionately and equitably in the true value of

7

Eon’s valuable and profitable business, and future growth in profits and earnings, at a time when the Company is poised to increase its profitability.

22.Defendants’ fiduciary obligations require them to:

(a)act independently so that the interests of Eon’s public stockholders will be protected;

(b)adequately ensure that no conflicts of interest exist between defendants’ own interests and their fiduciary obligation of entire fairness or, if such conflicts exist, to ensure that all the conflicts are resolved in the best interests of Eon’s public stockholders; and

(c)provide Eon’s stockholders with genuinely independent representation in any negotiations with Novartis.

23.Because Novartis controls Eon, no auction or market check can be effected to establish Eon’s worth. Thus, Novartis has the power and is exercising its power to acquire Eon’s minority shares and dictate terms which are in Novartis’ best interest, without competing bids and regardless of the wishes or best interests of class members or the intrinsic value of Eon’s stock.

24.By reason of the foregoing, defendants have breached and will continue to breach their duties to the minority public shareholders of Eon and are engaging in improper, unfair dealing and wrongful and coercive conduct.

25.Plaintiff and the Class will suffer irreparable harm unless defendants are enjoined from breaching their fiduciary duties and from carrying out the aforesaid plan and scheme.

26.By reason of the foregoing, defendants have violated the fiduciary duties which each of them owes to plaintiff and the other members of the Class.

27.Each of the defendants has colluded in and rendered substantial assistance in the accomplishment of the wrongdoing complained of herein. In taking the actions, as particularized

8

herein, to aid and abet and substantially assist the wrongs complained of, all defendants acted with an awareness of the primary wrongdoing and realized that their conduct would substantially assist the accomplishment of that wrongdoing and were aware of their overall contribution to the conspiracy, common scheme and course of wrongful conduct.

28.Unless enjoined by this Court, defendants will continue to breach their fiduciary duties owed to plaintiff and the other members of the Class, and are prepared to consummate a buyout on unfair and inadequate terms which will exclude the Class from its fair proportionate share of Eon’s valuable assets and businesses, all to the irreparable harm of the Class, as aforesaid.

29.Plaintiff and the other class members are immediately threatened by the acts and transactions complained of herein, and lack an adequate remedy at law.

WHEREFORE, plaintiff demands judgment and preliminary and permanent relief, including injunctive relief, in its favor and in favor of the Class and against defendants as follows:

A.Declaring that this action is properly maintainable as a class action, and certifying plaintiff as a class representative;

B.Declaring that the defendants and each of them have committed or participated in a gross abuse of trust and have breached their fiduciary duties to plaintiff and other members of the Class or aided and abetted such breaches;

C.Enjoining the Proposed Transaction and, if the transaction is consummated, rescinding the transaction;

D.Awarding plaintiff and the Class compensatory damages and/or rescissory damages;

9

E.Awarding plaintiff the costs and disbursements of this action, including allowance for plaintiff’s attorneys’ and experts’ fees;

F.Granting such other, and further relief as this Court may deem to be just and proper.

DATED:  February 23, 2005
	MILBERG WEISS BERSHAD & SCHULMAN LLP
	By:	/s/ Seth D. Rigrodsky
	Seth D. Rigrodsky (#3l47)
	Ralph N. Sianni (#4151)
	919 N. Market Street, Suite 411
	Wilmington, DE 19801
	Tel: (302) 984-0597
	Fax: (302) 984-0870
	-and-
	One Pennsylvania Plaza
	New York, NY 10119-0165
	Tel: (212) 594-5300
	Fax: (2l2) 868-1229
	Bruce G. Murphy, Esq.
	Law Offices of Bruce G. Murphy
	265 Llwyds Lane
	Vero Beach, FL 32963
	Tel: (772) 231-4202
	Fax: (772) 234-6608
	Attorneys for Plaintiff

10

EX-99.(A)(6)(E)

Exhibit (a)(6)(E)

SUPREME COURT OF THE STATE OF NEW YORK COUNTY OF NEW YORK		NEW YORK COUNTY CLERK'S OFFICE
		FEB 23 2005
CHRISTOPHER PIZZO, individually and on behalf of all others similarly situated,	: :
	:	NOT COMPARED
Plaintiff,	:	WITH COPY FILED
v.	:	No.
	:
NOVARTIS AG, NOVARTIS CORPORATION, EON LABS INC., FRANK F. BEELITZ, BERNHARD HAMPL, DOUGLAS M. KARP, MARK R. PATTERSON, and THOMAS STRÜNGMANN,	: : : : : :	CLASS ACTION COMPLAINT
	:
Defendants.	:

Plaintiff alleges upon information and belief, except for paragraph 5 hereof, which is alleged upon personal knowledge, as follows:

SUMMARY OF ACTION

1.Plaintiff brings this case as a class action on behalf of himself and all other shareholders of Eon Labs, Inc. (“Eon” or the “Company”) who are similarly situated for injunctive and other appropriate relief in connection with the proposed acquisition of Eon by Novartis AG (“Novartis AG”), Eon’s majority shareholder.

2.Under the terms of the proposed merger, the merger consideration which Eon’s minority public shareholders will receive is inadequate and unfair.

JURISDICTION AND VENUE

3.This Court has personal Jurisdiction over the Defendant pursuant to §§ 301 and 302 of the New York Civil Practice Law and Rules (“CPLR”) in that Defendants reside in this States, are incorporated in this State and/or transact business in this State.

4.Venue is proper in this County pursuant to CPLR § 503 in that, on information and belief, Defendant Mark R. Patterson and Douglas M. Karp reside in this County.

THE PARTIES

5.Plaintiff Christopher Pizzo owns 200 shares of Eon common stock and has owned such shares at all material times.

6.Defendant Novartis AG (“Novartis AG”) is a company incorporated in Switzerland and maintains corporate headquarters at Lichtstrasse 35, 4056 Basel, Switzerland. Novartis is a world leader in pharmaceuticals and consumer health. It is a public company with American Depositary Shares (“ADS”) trading on the New York Stock Exchange.

7.Defendant Novartis Corporation (“Novartis Corp.”) is a New York Corporation located at 180 Park Avenue, Florham Park, NJ 07932. Novartis Corp. is a wholly owned subsidiary of Novartis AG.

8.Defendant Eon Labs Inc. (“Eon” or the “Company”) is incorporated under the laws of Delaware and maintains corporate headquarters at 1999 Marcus Avenue, Lake Success, NY 11042. Eon is a generic pharmaceutical company engaged in developing, licensing, manufacturing, selling and distributing a broad range of prescription pharmaceutical products primarily in the United States. As of November 8, 2004, there were 88,823,124 shares of common stock (“Common Stock”) outstanding. The Common Stock has one vote per share.

9.Frank F. Beelitz (“Beelitz”) has been a Director since February 2002. Beelitz has been the General Partner of Beelitz &Cie., an investment banking advisory firm, since July 2000. Mr. Beelitz was a Managing Director of Lehman Brothers Inc. and was a member of the management board and co-head of Lehman Brothers Bankhaus AG from July 1993 to July 2000. Prior to joining

2

Lehman Brothers Inc., Mr. Beelitz was a Managing Director with Salomon Brothers Inc. and a member of the management board and co-head of Salomon Brothers AG for seven years. Mr. Beelitz received a degree in banking from Bethmann Schule and received a Certificat d’Etudes Francaises from the Université de Grenoble, France.

10.Bernhard Hampl, Ph.D. (“Hampl”) has served as Eon’s Chief Executive Officer since October 1995 and a Director since September 1995. In January 1996, Dr. Hampl became President. From May 1995 to October 1995, Hampl was employed by Hexal AG to evaluate the possibility of establishing a U.S. subsidiary. From April 1980 until May 1995, Hampl held various positions with both Cyanamid GmbH and its business unit Durachemie GmbH, including Department Head of Research and Development, where he was responsible for research and development activities in Germany for the medical, agricultural and veterinary business of Cyanamid GmbH; Technical Director, where he was responsible for quality, manufacturing, logistics, research and development; and Plant Director. Hampl was significantly involved in an internal task force formed to restructure the European operations of Cyanamid GmbH. Hampl received his Bachelor’s Degree in Pharmaceutical Sciences and a Ph.D. in Pharmaceutical Chemistry from Ludwig Maximillian University of Munich.

11.Douglas M. Karp (“Karp”) is a Director of Eon and currently the Managing Partner at Pacific Partners, LLC, a private equity and advisory firm focused on communications, media and technology companies. Prior to joining Pacific Partners, Mr. Karp was a Managing Director and member of the Operating Committee at E.M. Warburg Pincus & Co., LLC where he was responsible for a private equity portfolio of approximately $14 billion focused on Communications, Media and Restructuring. Prior to this position, he served as a Managing Director of Mergers and Acquisitions

3

at Salomon Brothers Inc. In addition to Eon Labs, Mr. Karp serves on the Board of City Parks Foundation of New York andHorizons National Education Program. Mr. Karp holds degrees from Yale University and Harvard Law School.

12.Mark R. Patterson (“Patterson”) is a Director of Eon and currently the Chairman of MatlinPatterson Asset Management LLC, which manages MatlinPatterson Global Opportunities Partners, L.P., a $2.2 billion merchant banking distressed fund. Previously, Mr. Patterson was a Managing Director of Credit Suisse First Boston Corporation, as well as Vice Chairman with an emphasis on Leveraged Finance businesses. Mr. Patterson also served as Vice Chairman of Credit Suisse First Boston Corporation and served on its Global Operating Committee. In addition to Eon Labs, Mr. Patterson is an Advisory Board member of K Capital Partners LLC, a Boston-based hedge fund. Mr. Patterson holds degrees in law and economics from South Africa’s Stellenbosch University and an MBA from New York University’s Stern School of Business.

13.Thomas Strüngmann, Ph.D. (“Strüngmann”) has served as Chairman of the Board of Directors since September 1995. Strüngmann co-founded Hexal AG in 1986 and has served as its Co-Chief Executive Officer and Co-President since then. Strüngmann served as Chief Executive Officer of Durachemie GmbH. Strüngmann received a B.S. degree in economics from the University of Munich and a Ph.D. from the University of Augsburg, Germany. Chairman of the Board of Directors.

14.Defendants Beelitz, Hampl, Karp, Patterson, and Strüngmann, constitute the entirety of Eon’s Board of Directors These defendants are hereinafter referred to collectively as the “Individual Defendants.”

15.By virtue of the Individual Defendants’ positions as officers and/or directors of Eon,

4

each of them is in a fiduciary relationship with plaintiff and the other public shareholders of Eon and owesplaintiff and the other public shareholders the highest obligations of good faith, fair dealing, loyalty and due care.

CLASS ACTION ALLEGATIONS

16.Plaintiff brings this action on his own behalf and as a class action pursuant to Article 9 of the CPLR on behalf of the holders of Eon Common Stock (the “Class”). Excluded from the Class are defendants herein and any person, firm, trust, corporation, or other entity related to or affiliated with any of the defendants.

17.18.This action is properly maintainable as a class action because:

(a)The class is so numerous that joinder of all members is impracticable. There are about 88 million shares of Eon common stock outstanding beneficially owned by thousands of shareholders.

(b)There are questions of law and fact which are common to the Class including the following:

1.whether the individual Defendants have breached their fiduciary and other common law duties owed by them to plaintiff and the other members of the Class;

2.whether defendants are imposing an unfair transaction on the Company’s public shareholders; and

3.whether the Class is entitled to injunctive relief for damages as a result of Defendants’ wrongful conduct.

(c)Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff’s claims are typical of the claims of other

5

members of the Class and plaintiff has the same interests as the other members of the Class.

(d)Defendants have acted in a manner which affects plaintiff and all other members of the Class alike, thereby making appropriate injunctive relief and/or corresponding declaratory relief with respect to the Class as a whole.

(e)The prosecution of separate actions by individual members of the Class would create the risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the Class which would as a practical matter be dispositive of the interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interests.

SUBSTANTIVE ALLEGAT1ONS

18.On Monday, February 21, 2005, Eon announced it had signed a definitive merger agreement pursuant to which Novartis AG will acquire Eon. Novartis AG will buy all of Hexal AG (“Hexal”) and the two-thirds of Eon shares that Hexel owns, in addition to Novartis Corp. buying the remaining one-third of Eon’s publicly held shares for $31.00 per share in cash. Novartis AG would then merge Hexal and Eon into its Sandoz unit.

19.The $31.00 per share offered for Eon’s common stock is inadequate and unfair.

The Merger

20.The detailed terms of the merger agreement are as follows.

21.Novartis AG entered into an agreement with Santo Holding (Deutschland) GmbH (“Santo”) (Eon and Hexal’s controlling stockholder) to acquire all of the 60 million shares of Eon’s common stock held by Santo for EUR 1.3 billion in cash (approximately $1.7 billion).

6

22.Novartis AG also agreed with Santo to purchase all of privately held Hexal, one of the largest generic pharmaceutical companies in Germany, including Eon shares Hexel holds directly (and indirectly by Defendant Strüngmann and an indirect significant shareholder of Santo), for an estimated EUR 4.35 billion in cash (approximately $3.95 billion).

23.Novartis Corp., a wholly-owned subsidiary of Novartis AG, will then commence a cash tender offer to acquire all the remaining outstanding publicly held shares of Eon common stock not held by Santo at a price of $31.00 per share (approximately $1 billion).

24.Both Eon and Hexal will be merged with Novartis AG’ Sandoz unit, creating the world’s leading generics company based on global revenues.

25.The transactions are expected to close in the second half of 2005. The combined company, which will operate under the Sandoz name, will have combined pro forma 2004 sales of approximately $5.1 billion, a portfolio consisting of more than 600 drugs and employ over 20,000 people worldwide.

26.Following the consummation of the transactions, Defendant Hampl will serve as CEO of Sandoz U.S., Novartis AG’s generic pharmaceutical business based in the United States.

27.Eon further announced that the Board of Directors of Eon and a Special Committee of independent members of Eon’s Board of Directors determined that the terms of the tender offer and merger are fair to, and in the best interests of, Eon and its stockholders not affiliated with Santo, and have recommended that the public stockholders accept the offer.

The Value of Eon’s Common Stock

28.On Friday, February 18, 2005, the trading day prior to the merger’s announcement, Eon’s shares closed at $27.92. The merger terms thus represent a premium of only $3.08 (or 10%)

7

for Eon’s roughly 31.9 million publicly held shares not held by Santo or Hexal.

29.That 10% premium being offered is inadequate and unfair given Eon’s strong financial condition.

30.For example, on the same day of the merger announcement, Eon announced that it expects net income of $30.2 million for the fourth quarter ended December 31, 2004, compared to $19.2 million in the comparable quarter in 2003, an increase of 57.3%.

31.Diluted earnings per share is expected to be $0.33 for the fourth quarter ended December 31, 2004, compared to $0.21 for the comparable quarter in 2003, an increase of 57.1%.

32.Analyst coverage concluded similarly.

33.For example, Credit Suisse First Boston (“CSFB”) in a report issued on February 9, 2005, just days before the merger announcement, stated a price target of $36.00 for Eon. In fact, CSFB based that price target on expected earnings per share of $0.29, which was below Eon’s announced earnings per share of $0.33.

34.Similarly, Lazard Freres & Co. LLC (“Lazard”) in a report issued on February 10, 2005, set a target price for Eon at $37.00.

35.In both cases, it is clear that the small premium offered for Eon’s common stock was well below its true and fair value.

BREACH OF FIDUCIARY DUTY

36.Plaintiff repeats the preceding paragraphs as if fully set forth herein.

37.By reason of their position and/or majority ownership of Eon common stock, the Defendants owe fiduciary duties to Plaintiff and the Class members.

38.By reason of the foregoing, Novartis AG and Novartis Corp. have breached, are

8

breaching and are aiding and abetting in a breach of their fiduciary duties to Plaintiff and the members of the Class and to the detriment and at the expense of Plaintiff and the Class members.

39.By reason of the foregoing, EON and the Individual Defendants have breached and are breaching their fiduciary duties to Plaintiff and the members of the Class and to the detriment and at the expense of Plaintiff and the Class members.

40.Plaintiff has no adequate remedy at law.

9

RELIEF REQUESTED

WHEREFORE, plaintiff prays for judgment and relief as follows:

A.Ordering that this action may be maintained as a class action and certifying plaintiff as the Class representative;

B.Preliminarily and permanently enjoining defendants and all persons acting in concert with them, from proceeding with, consummating or closing the proposed merger;

C.In the event the proposed merger is consummated, rescinding it and setting it aside or awarding rescissory damages to the Class;

D.Directing defendants to account to Class members for their damages sustained as a result of the wrongs complained of herein;

E.Awarding plaintiff the costs of this action, including a reasonable allowance for plaintiff’s attorneys’ and experts’ fees;

Dated:	February 23, 2005
	New York, New York
		SARRAF GENTILE LLP
		/s/ Ronen Sarraf
		Ronen Sarraf
		Joseph Gentile
		111 John Street, 8th Floor
		New York, NY 10038
		T: 212-433-1312
		F: 212-406-3677
		VIANALE & VIANALE LLP
		Kenneth J. Vianale
		The Plaza - Suite 801
		5355 Town Center Road
		Boca Raton, Florida 33486
		T: 561-391-4900
		LAW OFFICES OF BRUCE G. MURPHY
		Bruce G. Murphy
		265 Llwyds Lane,
		Vero Beach, Florida 32963,
		T: 772-231-4202

10

EX-99.(A)(6)(F)

Exhibit (a)(6)(F)

EFiled: Mar 1 2005 11:36 AM EST

Filing ID 5241128

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE
IN AND FOR NEW CASTLE COUNTY

	X
ERSTE SPARINVEST	:
KAPITALANLAGEGESELLSCHAFT MBH	:
	:
Plaintiff,	:
	:	C.A. No.
vs.	:
	:
EON LABS, INC., NOVARTIS AG, THOMAS	:
STRUNGMANN, BERNHARD HAMPL, MARK R.	:
PATTERSON, FRANK F. BEELITZ, and	:
DOUGLAS M. KARP,	:
	:
Defendants.	X

SHAREHOLDER’S CLASS ACTION COMPLAINT

Plaintiff, through counsel, for its complaint against defendants, alleges upon personal knowledge with respect to paragraph 2 and upon information and belief based, inter alia, upon the investigation of counsel, as to all other allegations herein, as follows:

NATURE OF THE ACTION

1.This is a stockholder’s class action on behalf of the public stockholders of defendant Eon Labs, Inc. (“Eon” or the “Company”), against certain of its officers and directors and others to enjoin the proposed acquisition of the outstanding shares of Eon common stock by defendant Novartis AG (“Novartis”).  As set forth below, Novartis has entered into two definitive agreements, the first of which involves the acquisition of Hexal AG (“Hexal”), a privately owned German pharmaceutical company that holds approximately 67.7% of Eon through a subsidiary company, and the second of which is a merger agreement with Eon pursuant to which a wholly-owned subsidiary of Novartis will commence a cash tender offer to acquire all

Eon shares not held by the Hexal subsidiary (the “Proposed Transaction”). Novartis then intends to effect a merger to acquire all remaining Eon shares at the offer price of $31.00 per share (the “Merger”).

THE PARTIES

2.Plaintiff Erste Sparinvest Kapitalanlagegesellschaft MBH is and at all relevant times has been an owner of Eon common stock.

3.Defendant Eon is a Delaware corporation with its principal executive offices located at 227-15 North Conduit Ave., Laurelton NY 11413. Eon is one of the largest suppliers of generic pharmaceuticals in the United States. Eon produces a broad range of pharmaceuticals in a wide variety of therapeutic categories. Eon maintains a diverse product line consisting of more than 200 products representing various dosage strengths for over 60 drugs. As of November 8, 2004, Eon had over 88 million shares of common stock outstanding, held by hundreds if not thousands of shareholders of record. Eon common stock is listed and traded on NASDAQ NM under the ticker symbol ELAB.

4.Defendant Novartis is Europe’s fourth largest pharmaceutical company and is based in Basel, Switzerland. Novartis operates through 360 independent affiliates in 140 countries and offers its products and services through its Pharmaceutical and Consumer Health divisions. Upon its proposed acquisition of Hexal, Novartis will own approximately 67.7% of Eon. As such, Novartis will effectively control and dominate Eon’s affairs. Novartis, therefore, will be a controlling shareholder and owe fiduciary obligations of good faith, candor, loyalty and fair dealing to the public shareholders of Eon.

5.At all relevant times, defendants Thomas Strungmann (“Strungmann”), Bernhard Hampl (“Hampl”), Mark R. Patterson (“Patterson”), Frank F. Beelitz (“Beelitz”), and Douglas

2

M. Karp (“Karp”) have served as the directors of Eon (collectively, the “Individual Defendants”).

6.In addition, at all relevant times, defendant Strungmann has served as Eon’s Chairman of the Board and defendant Hampl has served as Eon’s President and Chief Executive Officer. Furthermore, in 1986, defendant Strungmann co-founded Hexal with his twin brother and has served as Co-CEO and Co-President of Hexal since its inception. From May 1995 to October 1995, defendant Hempl was employed by Hexal to evaluate opportunities for Hexal to establish a U.S. subsidiary.

7.By virtue of their positions as directors and/or officers of Eon and/or their exercise of control and dominant ownership over the business and corporate affairs of Eon, each and every of the Individual Defendants and Novartis have, and at all relevant times had, the power to control and influence, and did control and influence and cause Eon to engage in the practices complained of herein. Each Individual Defendant and Novartis owed and owes Eon and its stockholders fiduciary obligations and were and are required to: use their ability to control and manage Eon in a fair, just and equitable manner; act in furtherance of the best interests of Eon and its stockholders; govern Eon in such a manner as to heed the expressed views of its public shareholders; refrain from abusing their positions of control; and not to favor their own interests at the expense of Eon and its stockholders.

8.As discussed in detail below, Novartis, in concert with the Individual Defendants, as well as the Individual Defendants, who together control the actions of Eon, have breached their fiduciary duties to Eon’s public stockholders by acting to cause or facilitate Novartis’ acquisition of the publicly-held minority shares of Eon for unfair and inadequate consideration, and colluding in Novartis’ coercive tactics in accompanying such buyout.

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9.Each defendant herein is sued individually as a conspirator and aider and abettor, as well as in the case of the Individual Defendants, in their capacity as directors and/or officers of Eon and the liability of each arises from the fact that they have engaged in all or part of the unlawful acts, plans, schemes, or transactions complained of herein.

CLASS ACTION ALLEGATIONS

10.Plaintiff brings this action pursuant to Rule 23 of the Rules of this Court, on behalf of itself and all other shareholders of the Company except the defendants herein and any persons, firm, trust, corporation, or other entity related to or affiliated with them and their successors in interest, who are or will be threatened with injury arising from defendants’ actions, as more fully described herein (the “Class”).

11.This action is properly maintainable as a class action for the following reasons:

(a)The Class is so numerous that joinder of all members is impracticable. There are millions of shares of Eon common stock which are outstanding, held by hundreds, if not thousands, of stockholders who are members of the Class.

(b)Members of the Class are scattered throughout the United States and are so numerous that it is impracticable to bring them all before this Court.

(c)There are questions of law and fact that are common to the Class and that predominate over any questions affecting individual class members. The common questions include, inter alia, the following:

(i)Whether defendants have engaged in and are continuing to engage in conduct which unfairly benefits Novartis at the expense of the members of the Class;

(ii)Whether the Individual Defendants, as officers and/or directors of the Company, and Novartis, the controlling stockholder of Eon are violating their fiduciary duties to plaintiff and the other members of the Class;

4

(iii)Whether plaintiff and the other members of the Class would be irreparably damaged were defendants not enjoined from the conduct described herein;

(iv)Whether defendants have initiated and/or timed their buyout of Eon shares to unfairly benefit Novartis at the expense of Eon’s public shareholders.

(d)The claims of plaintiff are typical of the claims of the other members of the Class in that all members of the Class will be damaged by defendants’ actions.

(e)Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff is an adequate representative of the Class.

(f)Plaintiff anticipates that there will not be any difficulty in the management of this litigation as a class action.

12.The class action is superior to any other method available for the fair and efficient adjudication of this controversy since it would be impractical and undesirable for each of the members of the Class who has suffered or will suffer damages to bring separate actions in various parts of the country.

SUBSTANTIVE ALLEGATIONS

13.On February 21, 2005, Novartis announced that it had entered into two definitive agreements. First, Novartis agreed to acquire 100% of Hexal, a privately-held company that held a 67.7% stake (65.4% fully diluted) in Eon through a subsidiary, namely Santo Holding (Deutschland) AG (“Santo”). Second, Novartis announced a definitive merger agreement with Eon pursuant to which an affiliate of Novartis will commence a tender offer to acquire all outstanding publicly held shares of Eon not held by Santo at a price of $31.00 per share in cash.

14.Also on February 21, 2005, Eon announced that its board of directors, and a purportedly independent special committee thereof (the “Special Committee”) had determined

5

that the Proposed Transaction and Merger were fair to Eon’s public shareholders and recommended that the public shareholders accept the $31.00 per share tender offer.  Eon further announced that both Hexal and Novartis would be merged into Novartis’ Sandoz unit, and that following the transactions defendant Hampl would become CEO of Sandoz U.S., Novartis’ generic pharmaceutical unit based in the United States.  It has also been reported that following the transactions Strungmann and his twin brother will take executive positions within Sandoz.

15.Both the Novartis and Eon press releases touted the outstanding recent financial performance of Eon. Novartis’ announcement noted that “over the past three years alone, Eon labs has produced 15 first-to-market launches and has positioned itself as the market share leader for nearly half of the products in its portfolio.” Eon released its preliminary financial results in the same news release announcing the Proposed Transaction and noted, among other things, that net income for the fourth quarter ended December 31, 2004 would increase by 57.3% while diluted earnings per share would increase by 57.1%. Eon also announced its expectation that net income for the year ended December 31, 2004 would increase by 70.2% and that “diluted earnings per share is expected to be a record $1.32 compared to $0.77 per share for the year 2003, an increase of 71.4%.” Eon also stated that “net sales were a record $431.0 million for the year ended December 31, 2004, compared to $329.5 million for the year 2003, an increase of 30.8%” and that “at December 31, 2004, Eon had $195.8 million of cash and short-term investments and no outstanding debt.”

16.In its press release of February 21, 2005, Novartis also noted that Eon “has a strategic partnership with Hexal AG” and that defendant Strungmann, along with his brother and their families “hold a 67.7% stake in Eon Labs through a holding company.” Given defendant Strungmann’s influence as an officer of Hexal and a director of Eon, the two companies do

6

significant business together, including business related to the drug Cyclosporine, and have entered into various licensing and product agreements.

17.By virtue of its acquisition of Hexal, Novartis is a majority owner of Eon and is, therefore, well aware of the status of Eon’s development and success. In making its inadequate offer to acquire the remaining stock of Eon, Novartis has tried to take advantage of the fact that the market price of Eon stock does not fully reflect the progress and future value of the Company.

18.The value of $31.00 per share to be paid to the class members is unconscionable, unfair and grossly inadequate and constitutes unfair dealing because, among other things, (a) the intrinsic value of the stock of Eon is materially in excess of the $31.00 value, giving due consideration to the possibilities of growth and profitability of Eon in light of its business, earnings and earnings power, present and future; (b) the $31.00 value is inadequate and offers only a 5.7% premium over Eon’s 52-week average to the public stockholders of Eon; and (c) the $31.00 value is not the result of arm’s-length negotiations, but was fixed arbitrarily by Novartis to “cap” the market price of Eon stock, as part of a plan for Novartis to obtain complete ownership of Eon at the lowest possible price. The intrinsic unfairness in defendants’ actions is also the product of the currently undervalued price of the shares in the marketplace.

19.Because Novartis is in possession of proprietary corporate information concerning Eon’s future financial prospects, the degree of knowledge and economic power between Novartis and the class members is unequal, making it grossly and inherently unfair for Novartis to obtain the remaining Eon shares at the unfair and inadequate price that it has proposed.

20.By offering grossly inadequate value for Eon’s shares and threatening or planning to use its coercive means of control to force the consummation of the transaction, Novartis is violating its duties as a majority shareholder.

7

21.Any buyout of Eon public shareholders by Novartis on the terms recently offered will deny class members their right to share proportionately and equitably in the true value of Eon’s valuable and profitable business, and future growth in profits and earnings, at a time when the Company is poised to increase its profitability.

22.Defendants’ fiduciary obligations require them to:

(a)act independently so that the interests of Eon’s public stockholders will be protected;

(b)adequately ensure that no conflicts of interest exist between defendants’ own interests and their fiduciary obligation of entire fairness or, if such conflicts exist, to ensure that all the conflicts are resolved in the best interests of Eon’s public stockholders; and

(c)provide Eon’s stockholders with genuinely independent representation in any negotiations with Novartis.

23.Because Novartis controls Eon, no auction or market check can be effected to establish Eon’s worth. Thus, Novartis has the power and is exercising its power to acquire Eon’s minority shares and dictate terms which are in Novartis’ best interest, without competing bids and regardless of the wishes or best interests of class members or the intrinsic value of Eon’s stock.

24.By reason of the foregoing, defendants have breached and will continue to breach their duties to the minority public shareholders of Eon and are engaging in improper, unfair dealing and wrongful and coercive conduct.

25.Plaintiff and the Class will suffer irreparable harm unless defendants are enjoined from breaching their fiduciary duties and from carrying out the aforesaid plan and scheme.

26.By reason of the foregoing, defendants have violated the fiduciary duties which each of them owes to plaintiff and the other members of the Class.

8

27.Each of the defendants has colluded in and rendered substantial assistance in the accomplishment of the wrongdoing complained of herein. In taking the actions, as particularized herein, to aid and abet and substantially assist the wrongs complained of, all defendants acted with an awareness of the primary wrongdoing and realized that their conduct would substantially assist the accomplishment of that wrongdoing and were aware of their overall contribution to the conspiracy, common scheme and course of wrongful conduct.

28.Unless enjoined by this Court, defendants will continue to breach their fiduciary duties owed to plaintiff and the other members of the Class, and are prepared to consummate a buyout on unfair and inadequate terms which will exclude the Class from its fair proportionate share of Eon’s valuable assets and businesses, all to the irreparable harm of the Class, as aforesaid.

29.Plaintiff and the other class members are immediately threatened by the acts and transactions complained of herein, and lack an adequate remedy at law.

WHEREFORE, plaintiff demands judgment and preliminary and permanent relief, including injunctive relief, in its favor and in favor of the Class and against defendants as follows:

A.Declaring that this action is properly maintainable as a class action, and certifying plaintiff as a class representative;

B.Declaring that the defendants and each of them have committed or participated in a gross abuse of trust and have breached their fiduciary duties to plaintiff and other members of the Class or aided and abetted such breaches;

C.Enjoining the Proposed Transaction and, if the transaction is consummated, rescinding the transaction;

9

D.Awarding plaintiff and the Class compensatory damages and/or rescissory damages;

E.Awarding plaintiff the costs and disbursements of this action, including allowance for plaintiff’s attorneys’ and experts’ fees;

F.Granting such other, and further relief as this Court may deem to be just and proper.

DATED:   March 1, 2005
	MILBERG WEISS BERSHAD & SCHULMAN LLP
	By:	/s/ Seth D. Rigrodsky
	Seth D. Rigrodsky (#3l47)
	Ralph N. Sianni (#4l51)
	919 N. Market Street, Suite 411
	Wilmington, DE 19801
	Tel: (302) 984-0597
	Fax: (302) 984-0870
	-and-
	Deborah M. Sturman
	One Pennsylvania Plaza
	New York, NY 10119-0165
	Tel: (212) 594-5300
	Fax: (2l2) 868-1229
	Attorneys for Plaintiff

10

EX-99.(A)(6)(G)

Exhibit (a)(6)(G)

EFiled: Mar 1 2005 5:23 PM EST

Filing ID 5246722

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

MERL HUNTSINGER,	:
	:
Plaintiff,	:
	:	C.A. No.
v.	:
	:
EON LABS, INC, DR. THOMAS STRÜNGMANN, BERNHARD HAMPL, MARK R. PATTERSON, FRANK F. BEELITZ, DOUGLAS M. KARP, SANTO HOLDING (DEUTSCHLAND) GmbH, NOVARTIS CORPORATION, and ZODNAS ACQUISITION CORP.,	: : : : : : :
	:
Defendants.	:

COMPLAINT

Plaintiff, Merl Huntsinger, a holder of 1000 shares of common stock of Eon Labs, Inc. (“Eon” or the “Company”), brings this action individually and as a class action on behalf of the Company’s shareholders, except defendants and their affiliates, to remedy breaches of fiduciary duty by the individual defendants and to enjoin a self-dealing plan through which Novartis Corporation (“Novartis”) and its wholly owned subsidiary have agreed to acquire Hexal AG, Eon’s strategic partner, and to acquire the controlling shares of Eon and then to buy out the Eon public shareholders through a coercive tender offer (the “Tender Offer”) and a squeeze-out merger (the “Merger”). In the Tender Offer and Merger, Novartis proposes to purchase Eon’s outstanding public shares for $31.00 per share, only 11% more than the discounted minority market price for the public shares on the last trading day before the transactions were announced.

THE PARTIES

1.Plaintiff is an owner of common stock of Eon Labs, Inc. (“Eon”) and has been the owner of such shares continuously since prior to the wrongs complained of herein.

2.Defendant Eon is a corporation duly existing and organized under the laws of the State of Delaware, with principal executive offices in Lake Success, New York. The Company is a generic pharmaceutical company engaged in developing, licensing, manufacturing, selling and distributing a range of prescription pharmaceutical products primarily in the United States. Eon is one of the largest suppliers of generic pharmaceuticals in the United States. It reported record 2004 sales of $431 million, a 31% increase over 2003. Eon is and at all times relevant hereto was listed and traded on NASDAQ National Market. As of February 20, 2005, Eon had approximately 88.8 million common shares outstanding, and as of March 8, 2004, had approximately 17 holders of record of the Company’s common stock.

3.Defendant Dr. Thomas Strüngmann (“Strüngmann”) is and at all times relevant hereto has been Chairman of the Board of Eon. Strüngmann is a co-founder, Co-Chief Executive Officer and Co-President, together with his twin brother, Andreas Strüngmann, of Hexal AG (“Hexal”). Hexal, which has a strategic partnership with Eon, is wholly owned by the Strüngmann brothers and their families. Hexal is a manufacturer of generic pharmaceuticals and holds the Number 2 position in generics in Germany, the second largest generics market. Hexal had sales of $1.65 billion in 2004.

4.Defendant Santo Holding (Deutschland) GmbH (“Santo”) is the holder of 60 million shares of Eon common stock, representing approximately 67% of the issued and outstanding capital stock of Eon (the “Santo Shares” or “Controlling Shares”). Santo is owned by the Strüngmann brothers and their families.

5.Defendant Bernhard Hampl (“Hampl”) is and at all times relevant hereto has been Chief Executive Officer and a director of the Company. Hampl was employed by Hexal for a period of time during 1995 to evaluate the possibility of establishing a subsidiary in the United

2

States.

6.Defendant Mark R. Patterson is and at all times relevant hereto has been a director of Eon. Patterson has been a director of the Company since October 2002. His term as a Class III director expires at the Annual Meeting of Stockholders to be held in 2005. Patterson is Chairman of MatlinPatterson Global Advisers LLC, which manages distressed investment funds. He also serves on the board of Oxford Automotive, Inc. and NRG Energy, Inc. Patterson was one of two Eon directors who served on a Special Committee of the Board that approved the Tender Offer and Merger as fair to the Eon public stockholders (the “Special Committee”).

7.Defendant Frank F. Beelitz is and at all times relevant hereto has been a director of Eon. Beelitz has been a director of the Company since February 2002. His term as a Class I director expires at the Annual Meeting of Stockholders to be held in 2006. Beelitz is the General Partner of Beelitz &Cie, an investment banking advisory firm.

8.Defendant Douglas M. Karp is and at all times relevant hereto has been a director of Eon. Karp has been a director of the Company since October 2002. His term as a Class I director expires at the Annual Meeting of Stockholders to be held in 2006. Karp is the Managing Partner and Co-Chief Executive Officer of Tailwind Capital Partners, an investment management firm. Karp was the second member of the Special Committee.

9.The defendants referred to in paragraphs 3 and 5 through 8 are collectively referred to herein as the “Individual Defendants.”

10.Defendant Novartis Corporation (“Novartis”) is a New York corporation. It is a subsidiary of Novartis AG, a world leader in pharmaceuticals and consumer health products, which had sales of $28.2 billion in 2004.  Novartis has formed a wholly-owned subsidiary, defendant Zodnas Acquisition Corp., a Delaware corporation (“Zodnas”), to effectuate the

3

proposed transactions. Novartis and Zodnas, through their agreement, arrangement and understanding with Santo to purchase the Controlling Shares, are the beneficial owners of approximately 67.7% of the equity of Eon, and, therefore, are controlling shareholders of Eon.

11.By reason of the Individual Defendants’ positions with the Company as officers and/or directors, they owe fiduciary duties to plaintiff and the other public stockholders of Eon,including the highest obligations of good faith, due care, loyalty and full and candid disclosure.

12.By reason of Santo’s position as a controlling shareholder of Eon, Santo is in a fiduciary relationship with plaintiff and the other public stockholders of Eon, and owes plaintiff and the other members of the class the highest obligations of good faith, due care, loyalty and full and candid disclosure. By reason of their agreement, arrangement and understanding to acquire the Controlling Shares, Novartis and Zodnas are controlling shareholders of Eon and owe a fiduciary duly to plaintiff and the other members of the Class.

JURISDICTIONAL ALLEGATIONS

13.This Court has jurisdiction over Novartis pursuant to 10 Del. C. §3104. Novartis formed and incorporated its wholly owned subsidiary Zodnas in Delaware for the sole purpose of effecting the transactions challenged herein.  The Merger Agreement, to which Novartis is a party, is governed by Delaware law, and Novartis has consented to the exclusive jurisdiction of the State and federal courts of Delaware “in any suit, action or proceeding . . . based on any matter arising out of or in connection with, [the Merger] Agreement or the transactions contemplated [t]hereby.” The February 11, 2005 Confidentiality Agreement between Eon and Novartis described below is also governed by Delaware law and contains a Delaware forum selection clause. By virtue of its agreement, arrangement and understanding with Santos to purchase the Controlling Shares, Novartis is a controlling shareholder of Eon, a Delaware

4

corporation.

CLASS ACTION ALLEGATIONS

14.Plaintiff brings this action individually and as a class action, pursuant to Court of Chancery Rule 23, on behalf of all common stockholders of the Company (the “Class”). Excluded from the Class are the defendants herein and any person, firm, trust, corporation or other entity related to or affiliated with any of the defendants.

15.This action is properly maintainable as a class action.

16.The Class is so numerous that joinder of all members is impracticable.  As of February 20, 2005, there were approximately 88.8 million shares of Eon common stock outstanding, over 20 million of which are publicly held by thousands of beneficial owners.

17.There are questions of law and fact which are common to the Class and which predominate over questions affecting individual Class members, including whether the defendants have breached their fiduciary duties to the members of the Class.

18.Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff’s claims are typical of the claims of the other members of the Class and plaintiff has the same interests as the other members of the Class. Plaintiff is an adequate representative of the Class and will fairly and adequately protect the interests of the Class.

19.The prosecution of separate actions by individual members of the Class would create the risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the Class which would as a practical matter be dispositive of the interests of the other members not parties to the adjudications or substantially impair or

5

impede their ability to protect their interests.

20.Defendants have acted, or refused to act, on grounds generally applicable to, and causing injury to, the Class and, therefore, preliminary and final injunctive relief and corresponding declaratory relief on behalf of the Class as a whole is appropriate.

EON’S STATUS AS A FAST-GROWING GENERICS COMPANY

21.Eon is a premier generics company which is one of the fastest-growing generics pharmaceutical companies. Eon specializes in first-to-market generics. In the last three years, Eon has produced 15 first-to-market generic products and is the market share leader for nearly half the products in its portfolio.  It currently has 29 Abbreviated New Drug Applications (“ANDAs”) pending before the U.S. Food and Drug Administration (“FDA”) covering products with annual branded prescription drug sales of $14.6 billion. It has a strong position in the U.S. for “difficult to make” generics. Eon sells generic versions of drugs such as the antidepressant Wellbutrin and the diabetes medication Glucophage.

22.The generic pharmaceuticals industry is growing dramatically, particularly in the U.S. Between 2002 and 2007, pharmaceutical companies including GlaxoSmithKline Plc and AstraZeneca Plc will have lost patent protection worth an annual $82 billion in sales. Double digit growth is expected through 2010, when the generics business will be a $100 billion industry.

23.Eon’s diluted earnings per share for 2004 were $1.32, up 71.4% from the prior year. Its diluted earnings exceeded its prior guidance. Net sales for 2004 were $431 million, a 30.8% annual increase. At December 31, 2004, Eon had $545 million in assets and only $102 million in liabilities, including only $8.3 million of long term debt. As of year end 2004, Eon had nearly $420 million in current assets, including $59.5 million in cash, $136.3 million in short-term investments and $224.2 million in other current assets.

6

THE CONFIDENTIALITY AGREEMENT

24.On February 11, 2005, Novartis entered into a “Confidentiality Agreement” with Eon.  The Confidentiality Agreement was signed on behalf of Eon by Defendant Hampl as president and Chief Executive Officer.  The Agreement provides for Eon to furnish Novartis with “Evaluation Material” in order to allow Novartis “to evaluate a possible negotiated (except as permitted by this letter agreement) transaction” with Eon.

25.The Confidentiality Agreement contains standstill provisions for a 12 month “Restricted Period” from the date of the Confidentiality Agreement. Novartis agrees it will not, without the prior approval of a majority of the members of the Eon Special Committee and the Eon Board of Directors, acquire or seek to acquire in any manner beneficial ownership of any Eon stock other than the Santo Shares or as permitted or required by the agreement. The Confidentiality Agreement also restricts Novartis from the proxy solicitation unless it has purchased a sufficient amount of the Santo shares to constitute a majority of the outstanding Eon common stock. Novartis is also restricted from making publicly announced proposals except in connection with a purchase of a control block of the Santo Shares or in connection with a transaction approved by a majority of the Eon Board and the Special Committee “following [Novartis] entering into any agreement with respect to the acquisition of a Control Block and including, for the avoidance of doubt, an option agreement with respect thereto” or as otherwise permitted by the Confidentiality Agreement.

26.The Confidentiality Agreement also provides that if Novartis acquires a “Control Block” during the Restricted Period, it will “prior to the expiration of the Restricted Period, propose and use reasonable efforts to take all legally permissible actions to consummate a tender offer” to acquire the publicly held shares of Eon at a price per share “equal to the dollar equivalent value of the amount of Euro paid per Santo Share calculated as of the date of the

7

agreement to acquire the Santo Shares.” The Agreement further provides that if a majority of the Public Shares are tendered into the tender offer, Novartis will propose and use reasonable best efforts to consummate a merger in which all remaining Eon shares would be acquired at the tender office price.  The Confidentiality Agreement provides that it is governed by and to be construed in accordance with Delaware law and the parties thereto consent to the exclusive jurisdiction of the Delaware courts.

THE EMPLOYMENT AGREEMENTS

27.On February 11, 2005, the same date Eon entered into the Confidentiality Agreement, Eon entered into employment agreements with ten (10) Eon officers, including defendant Hampl. All the employment agreements contain change-in-control provisions which entitle the officers to substantial payments if they are terminated following a change in control. Of course, at the time Eon entered into these agreements, it knew that it was about to engage in a change-in-control transaction with Novartis. Indeed, Novartis has stated that it expects to achieve $200 million worth of cost savings following its acquisition of Hexal and Eon. On information and belief, part of the cost savings will be the result of terminating Eon officers, including some of those with change-in-control agreements.

THE HEXAL PURCHASE AGREEMENT

28.Novartis has entered into a Share and Partnership Interest Sale and Transfer Agreement (Notarial Deed of February 16/17, 2005) (the “Hexal Purchase Agreement”) for the purchase of all of the outstanding shares of Hexal, including shares held directly and indirectly by Dr. Strüngmann, his brother and their family members, for approximately $5.75 billion.

29.Novartis has entered into an Agreement for Purchase and Sale of Stock (the “Control Agreement”) “dated as of February 20, 2005,” with Santo to acquire all of Santo’s 60 million shares of Eon’s common stock for approximately $1.7 billion in cash, plus interest from

8

January 1, 2005. In the Control Agreement, Santo agrees in Section 6.1(b) to use its best efforts to “cause the Company to fulfill its covenants and obligations under the Company Merger Agreement.” In Section 6.1(c), Santo covenants that it will cause defendant Strüngmann to remain in his current position as an Eon officer through the closing of the stock sale.

THE MERGER AGREEMENT

30.On February 21, 2005, Novartis announced that it had entered into definitive agreements to acquire Hexal and Eon. Under the terms of the Eon Merger Agreement dated February 20, 2005, Zodnas will commence within 10 business days of the date of the agreement (i.e.,on or before March 4, 2005) a cash tender offer to acquire all outstanding publicly held shares of Eon common stock not held by Santo, Eon’s controlling stockholder, at a price of $31.00 per share in cash. The Tender Offer is not conditioned on a majority of the minority shares, or any minimum number of shares being tendered.

31.The Tender Offer will remain open for twenty Business Days. Section 1.1(b) of the Merger Agreement provides, however, that Zodnas may extend the Tender Offer for up to thirty Business Days if the conditions of the offer are not satisfied or waived. If at least 40% of the Public Shares have been tendered, the Merger Agreement allows Zodnas to extend the Tender Offer for up to ten additional Business Days after all of the offer’s conditions have been satisfied or waived in order to obtain the “Requisite Tender Amount,” which is defined as “a majority of the Public Shares” of Eon (i.e. “the outstanding shares of Company Common Stock other than the Santo Shares”).

32.If the shares tendered would raise Novartis’s ownership to at least 80%, Section 1.l(b) of the Merger Agreement allows yet another ten Business Day extension to try to achieve the 90%ownership contemplated by Section 3.5 of the Merger Agreement for a short-form

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merger under 8 Del. C.  §253.

33.           Once the tendered shares are accepted, Section 1.1(b) of the Merger Agreement requires that the Confidentiality Agreement be amended to permit Novartis and Zodnas to acquire Public Shares through “voluntary” transactions including tender offers and open market purchases.  Prior to February 11, 2006, the Confidentiality Agreement will not permit a merger which would cancel the remaining Public Shares prior to February 11, 2006 unless (i) a majority of the outstanding Public Shares vote in favor of the merger, or (ii) Novartis and its subsidiaries own at least 90% of Eon’s outstanding common stock and can effect a short-form merger. Significantly, while Section 1.1(b)(ii) provides that the consideration in a short form merger must be at least equal to the Tender Offer price, it contains no such requirement with respect to additional shares acquired through tender offers, open market purchases or other purportedly voluntary transactions, any merger pursuant to Section 1.1(b)(i) or any merger after February 11, 2006.

34.           Section 8.1(a) of the Merger Agreement makes it a condition of the obligation of Novartis, Zodnas and Eon to complete the Merger that “a majority of the Public Shares having been purchased in the Offer (the ‘Requisite Tender Amount’).” Because the definition of Public Shares includes all shares other than those owned by Santo, Eon shares owned by the defendants and other Eon insiders and by Hexal and its affiliates are considered public shares. This condition is “waivable only with the approval of the Special Committee.” Under Section 8.1(a), Novartis and Zodnas will not be required to proceed with the Merger if a majority of the public shareholders reject the Tender Offer.

THE TRANSACTIONS ARE NOT IN THE BEST INTERESTS
OF THE EON STOCKHOLDERS

35.           In the February 21, 2005 press release, defendant Strüngmann stated that the

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purpose of the transactions was to “secure the future of Hexal and its employees.” He said all options were reviewed “in the interests of the employees and the families.”

36.Novartis expects to realize $200 million of cost synergies within three years of the closing, including $100 million within 18 months.

37.While Eon’s public stockholders will not share in the future growth of Eon’s business, defendant Strüngmann will continue to head that business.  Defendant Hampl will manage the U.S. operations and report to Strüngmann.

38.Although the Individual Defendants have represented that the $31.00 per share offer is fair to the Eon public shareholders, in fact, the consideration to be paid to Class members is unconscionable, unfair and grossly inadequate.

39.The transaction actually represents a substantial discount to Eon’s minority public shareholders based on the intrinsic value of the Company. On March 1, 2005, Eon announced its financial results for the fourth quarter and year ended December 31, 2004. The Company announced net income of $30.2 million for the fourth quarter, compared to $19.2 million for the same quarter in 2003, an increase of 57.3%. Diluted earnings per share increased approximately 57%, to $0.33 for the fourth quarter ended December 31, 2004, compared to $0.21 for the same quarter in 2003. Eon’s net income for the year ended December 31, 2004 was $119.4 million, an increase of 70.2% over net income for 2003. At December 31, 2004, Eon had $195.8 million in cash and short-term investments and no outstanding debt.

THE OPTION AWARDS

40.In breach of their duties of loyalty, care and good faith, the Individual Defendants, and in particular Karp and Patterson, on February 16, 2005, just four days before executing the Merger Agreement, embarked on an option-granting spree of 485,000 Eon stock options to themselves and management (the “February 2005 Option Grants”). Rather than setting the

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exercise price at the ultimate Tender Offer/Merger price, the Individual Defendants, and in particular Karp and Patterson, locked in the exercise price at the then-closing market price, knowing that they and their insider friends would obtain an immediate benefit from (a) the Merger Agreement that they would be executing in a matter of days and (b) the impending announcement of the Company’s positive fourth quarter financial results.

41.           The Eon board’s Compensation Committee is responsible for, inter alia, recommending the awarding of stock options under the Company’s 2001 Stock Option Plan and the 2003 Stock Incentive Plan (the “Stock Option Plans”).  Defendants Hampl, Strüngmann, Karp and Patterson comprise the Compensation Committee.

42.           The Option Committee of the Compensation Committee is empowered to administer the Company’s Stock Option Plans and to grant options under the Stock Option Plans.  Defendants Karp and Patterson comprise the Option Committee.  Karp and Patterson also comprise the Special Committee.  According to the Company’s annual proxy statement filed with the Securities and Exchange Commission (the “SEC”) on April 27, 2004:  “In the event of a change in control, the Option Committee, in its discretion, may provide that all outstanding options granted will immediately vest.”

43.           In each of 2003 and 2004, Eon’s outside directors were awarded options to purchase Eon common stock.  According to Form 4s filed with the SEC in 2003 and 2004, each of defendants Patterson, Karp and Beelitz, were awarded options on March 4, 2003 and March 4, 2004.

44.           According to Form 4s filed with the SEC on February 17, 2005, each of defendants Patterson, Karp and Beelitz were awarded options to purchase 20,000 shares of Eon common stock on February 16, 2005, at an exercise price of $28.75 per share (the “2005

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Options”).  Unlike the options awarded on March 4, 2003 and March 4, 2004, the 2005 Options vested immediately.  Thus, just four days before entering into the Merger Agreement, Karp and Patterson granted to themselves and Beelitz fully vested options to purchase Eon common stock, and made the grants two-and-a-half weeks earlier than outside director options had been traditionally awarded to Eon’s outside directors.

45.           In addition to awarding fully vested options to themselves and Beelitz, Karp and Patterson also rewarded management with more than 400,000 options on February 16, 2005, at the same $28.75 exercise price.  According to Form 4s filed with the SEC on February 17, 2005, the employee recipients and amounts awarded are as follows:

Recipient	Title	Options Awarded
Frank J. Della Fera	VP Sales & Marketing	40,000
Jeffrey S. Bauer	VP Business Development	50,000
Shashank Upadhye	VP and Counsel	15,000
Rathnam Kumar	VP Manufacturing	20,000
Dr. Leon Shargel	VP Biopharmaceutics	4,000
David H. Gransee	Controller & Asst. Secretary	6,000
William F. Holt	VP Finance, Secretary, Treasurer, CFO	60,000
William B. Eversgerd	VP Plant Facilities	20,000
Dr. Pranab Bhattacharyya	VP Quality Management	20,000
Dr. Bernard Hampl	President & CEO	150,000
Sadie Ciganek	VP Regulatory Affairs	40,000
	Total	425,000

46.           In February 2004, Eon granted employee stock options approximately one week

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after publicly reporting its fourth quarter and year-end financial results.

47.           Pursuant to Section 3.l(d) of the Merger Agreement, upon the Merger becoming effective:

each outstanding option to purchase shares of [Eon] Common Stock under any employee stock option or compensation plan or arrangement of the Company (a “Company Option”), whether or not exercisable or vested, shall by virtue of the Merger . . . be cancelled and the holder thereof will receive . . . a cash payment with respect thereto equal to the product of (a) the excess, if any, of the Merger Consideration over the exercise price per share of such Company Option and (b) the number of shares of Company Common Stock issuable upon exercise of such Company Option (the “Option Cash Payment”).

Thus, under the terms of the Merger Agreement, the February Option Grants alone will result in $1,091,250 in cash payments to the outside directors and management.  The February Option Grants constitute wrongful self-dealing and a breach of the Individual Defendants’ duties of loyalty, care and good faith.

48.           The extraordinary option grants followed closely on the heals of new employment agreements for 10 of the 11 employees identified in paragraph 36 above.  On February 11, 2005, Eon entered into amended and restated employment agreements with Messrs. Hampl, Bauer, Eversgerd, Gransee, Bhattacharyya and Ms. Ciganek.  Eon also entered into employment agreements with Messrs. Della Fera, Kumar and Upadhye, providing for, inter alia, change of control severance provisions and lump sum payouts and vesting of stock options in the event they are terminated without cause prior to or after a change of control.

ABROGATION OF THE EON CERTIFICATE

49.           Article Seventh of the Eon Restated Certificate of Incorporation (the “Eon Certificate”) provides:

From and after the date (the “Written Consent Prohibition Trigger Date”) that Santo Holding (Deutschland) GmbH and its Affiliates (collectively “Santo”) own less than 40% of the then outstanding shares of Common Stock (and regardless of whether Santo, at any time after the Written Consent Prohibition Trigger Date,

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owns 40% or more of the then outstanding Common Stock), (i) no action required to be taken or that may be taken at any meeting of holders of Common Stock may be taken without a meeting and (ii) the power of holders of Common Stock to consent in writing, without a meeting, to the taking of any action is specifically denied.

Thus, by virtue of the transfer of the Controlling Shares from Santo to Novartis, Eon stockholders, including Novartis, are precluded from acting by written consent.  This includes any action purporting to remove any director.

50.           Pursuant to Article Fifth, Section D of the Eon Certificate, a “director of the Corporation may be removed only for cause.” “Cause” is defined as “(a) a final conviction of a felony involving moral turpitude or (b) willful misconduct that is materially or demonstrably injurious economically to the Corporation.”

51.           Article Fifth of the Eon Certificate provides for a classified board of three classes of directors, with each director’s term to expire at the third succeeding annual meeting of stockholders following his or her election.

52.           Article Eleventh of the Eon Certificate provides, inter alia, that “the affirmative vote of the holders of not less than 66 2/3 percent of the outstanding shares of the Corporation then entitled to vote upon the election of directors, voting together as a single class, shall be required to amend, repeal, or to adopt any provision inconsistent with, Article Fifth, . . . Seventh . . . or this Article Eleventh of this Certificate.”

53.           In blatant disregard of their duties to the public stockholders, the defendants have contractually agreed to install Novartis’s designees on the Eon board even before Novartis is capable of effecting, or required to effect, a Merger.  Section 1.3 provides, in pertinent part:

from and after the Acceptance Date, Novartis shall be entitled to designate each member of the Company’s Board of Directors, and the Company shall promptly take all actions necessary to cause Novartis’ designees to be so elected, including, if necessary, seeking the resignations of one or more existing directors and prior

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to the Acceptance Date removing any potential restrictions on the ability of any Novartis designees to serve on the Company’s Board of Directors . . . . (Emphasis added)

The “Acceptance Date” is defined in the Merger Agreement as the date that Zodnas “shall be obligated to accept for payment any and all Public Shares validly tendered and not validly withdrawn pursuant to the [Tender] Offer” (Emphasis added)

54.           Section 1.3 further provides that

if Novartis and the Company shall have purchased in the Offer . . . the Requisite Tender Amount [i.e., at least a majority of the outstanding shares of Company common stock other than the Santo Shares], then until the Effective Time, Novartis and [Zodnas] shall allow the members of the Special Committee or their designees’ who shall be deemed the “Special Committee” for all purposes of this Agreement, to remain on the Company’s Board of Directors provided, that if both of the members of the Special Committee shall be unable or unwilling to remain on the Company’s Board of Directors and neither shall have designated a replacement, Novartis shall be permitted to replace such members with other independent directors who shall be deemed the “Special Committee” for all purposes of this Agreement . . .

55.           Section 1.3 contractually abrogates the so-called protections provided by Eon’s classified board structure, and the prohibitions against action by stockholder written consent and the removal of directors for any reason other than for cause.  Section 1.3 effectively allows Novartis to install its designees on the Eon board before it effectuates a freeze-out merger.  In fact, it provides Novartis the power to install its director designees even before Novartis actually buys any Eon shares in the Tender Offer.

56.           Section 1.3 reduces the protections of the public stockholders’ rights and constitutes inequitable conduct and a breach of the defendants’ duties of care, loyalty and good faith.  Section 1.3 of the Merger Agreement is designed to eliminate the stockholders’ contractual protections under the Eon Certificate, including a classified board, the prohibition against action by stockholder written consent and the prohibition against removal of directors for any reason

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other than for cause.  The primary purpose Section 1.3 is to impede the effective exercise of the stockholder franchise by replacing the stockholders’ duly elected directors with Novartis designees.  Such inequitable conduct constitutes a breach of the Individual Defendants’ duties of loyalty and good faith.

THE COERCIVE TENDER OFFER

57.           The Tender Offer is not conditioned on a minimum number of shares being tendered Section 1.l(b) of the Merger Agreement states, in pertinent part:

Subject to the terms of the Offer and this Agreement and satisfaction of all the Tender Offer Conditions as of any Expiration Date, Novartis will cause [Zodnas] to accept for payment and pay for any and all Public Shares validly tendered and not validly withdrawn pursuant to the Offer at the earliest time after such Expiration Date, regardless of the number of Public Shares tendered in the Offer (such date as [Zodnas] shall be obligated to accept for payment any and all Public Shares validly tendered and not validly withdrawn pursuant to the Offer, the “Acceptance Date”).

58.           Section 1.1(b) of the Merger Agreement further provides:

On the Acceptance Date, the Confidentiality Agreement, dated as of February 11, 2005, by and between Novartis and the Company (the “Confidentiality Agreement”) shall be amended such that . . . Novartis and [Zodnas] [shall be permitted] to make acquisitions of Public Shares that are voluntary to the holders of Public Shares (such as by means of legally permissible open market purchases or tender offers), but shall not permit Novartis to cause a merger transaction (or other business combination) to be effected which would cancel Public Shares unless (i) a majority of the outstanding Public Shares vote in favor of such a transaction or (ii) Novartis and its Subsidiaries shall, at that time, own at least 90% of the outstanding [Eon] Common Stock . . . .

59.           Thus, even if Novartis does not acquire a total of 90% of Eon’s outstanding common stock in the Tender Offer, it will be permitted to acquire a sufficient number of shares in the market and then effect a short-form merger pursuant to 8 Del. C. §253 at $31.00 per share.

60.           Section 7.10 of the Merger Agreement provides that Novartis and Zodnas:

shall use their reasonable best efforts, following the Acceptance Date and until the earlier of (i) the Effective Time and (ii) February 11, 2006, to keep the Company’s Common Stock quoted for trading on the NASDAQ National Market, as long as

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the Company is required to be registered under the Exchange Act and satisfies the NASDAQ National Market listing standards (other than standards entirely within the Company’s control).

61.           This provision is illusory.  According to Eon’s SEC filings, the Company had approximately 17 holders of record of the Company’s common stock as of March 8, 2004.  Under Rule 12g5-l of the Exchange Act, Eon is eligible to deregister the common stock because it has fewer than 300 holders of record.  Thus, non-tendering stockholders are left with the prospect of holding shares in an illiquid stock with the likely prospect of being cashed out for $31.00 per share when Novartis is able to acquire a sufficient number of shares on the market to make it eligible to effect a freeze-out merger under 8 Del. C. §253.

THE MERGER IS UNFAIR

62.           Recognizing the Company’s strong performance and potential for continued growth, Defendants have determined to deny the Company’s public shareholders the opportunity to obtain fair value for their equity interest in Eon.  Novartis is paying the lowest possible price to Class members, even though the Individual Defendants, and Novartis as controlling shareholder, have a duty to maximize shareholder value.

63.           The Individual Defendants were and are under a duty:

a.to fully inform themselves of Eon’s market value before taking, or agreeing to refrain from taking, action;

b.to act in the interests of the equity owners;

c.to maximize shareholder value;

d.to obtain the best financial and other terms when the Company’s independent existence will be materially altered by a transaction;

e.to act in accordance with their fundamental duties of due care and loyalty.

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64.           By the acts, transactions and courses of conduct alleged herein, defendants, individually and as part of a common plan and scheme or in breach of their fiduciary duties to plaintiff and the other members of the Class, are attempting unfairly to deprive plaintiff and other members of the Class of the true value of their investment in Eon.

65.           Strüngmann, through his stock ownership in the Company and his position as Chairman of the Board of the Company, is able to dominate and control the other Individual Defendants.  Accordingly, none of the Individual Defendants can be expected to protect the Company’s public shareholders in the Tender Offer and Merger which are structured to benefit Strüngmann at the expense of Plaintiff and the Class.

66.           Also as a result of Strüngmann’s stock ownership and position of control, no third party will make a competing bid for the Company, since the success of any such bid would require the consent and cooperation of Strüngmann.

67.           Novartis knowingly aided and abetted the Individual Defendants’ foregoing breaches of fiduciary duties by structuring the transaction to include buyouts of the Controlling Shares and Hexal from the Strüngmann brothers and their families.

68.           Eon shareholders will, if the transaction is consummated, be deprived of the opportunity for substantial gains which the Company may realize.

69.           By reason of the foregoing acts, practices and course of conduct, defendants have failed to exercise ordinary care and diligence in the exercise of their fiduciary obligations toward plaintiff and the other Eon public stockholders.

70.           As a result of the actions of defendants, plaintiff and the other members of the Class have been and will be damaged in that they have not and will not receive their fair proportion of the value of Eon’s assets and businesses and will be prevented from obtaining

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appropriate consideration for their shares of Eon common stock.

71.           Unless enjoined by this Court, the defendants will continue to breach their fiduciary duties owed to plaintiff and the other members of the Class, and may consummate the proposed transaction which will exclude the Class from its fair proportionate share of Eon’s valuable assets and businesses, and/or benefit them in the unfair manner complained of herein, all to the irreparable harm of the Class, as aforesaid.

COUNT I

Breach of Fiduciary Duty
(The Tender Offer)

72.           Plaintiff repeats and realleges the preceding paragraphs as if fully set forth herein.

73.           The Individual Defendants owe fiduciary duties to plaintiff and the other public stockholders of Eon, including the highest obligations of good faith, due care, loyalty and full and candid disclosure.

74.           By reason of Santo’s position as a controlling shareholder of Eon, Santo and Strüngmann are in a fiduciary relationship with plaintiff and the other public stockholders of Eon, and owes plaintiff and the other members of the class the highest obligations of good faith, due care, loyalty and full and candid disclosure.

75.           By virtue of its agreement, arrangement and understanding to acquire the Controlling Shares, Novartis and Zodnas arc controlling stockholders of Eon.

76.           As controlling stockholders of Eon, Novartis and Zodnas owe fiduciary duties to plaintiff and the Class.  Santo and Strüngmann, as controlling stockholders of Eon owe fiduciary duties to plaintiff and the Class

77.           The Tender Offer is coercive and threatens to force Eon’s minority stockholders to accept an unfair transaction.  As a result of receiving the Evaluation Material pursuant to the

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Confidentiality Agreement, Novartis and Zodnas have used inside information belonging to Eon to foist an inadequate Tender Offer on Eon’s public shareholders.  Eon’s self-interested directors, including insiders such as Strüngmann and Hampl and option recipients such as Special Committee members Karp and Patterson, have failed to protect the minority’s interests.

78.           The Individual Defendants and Santo have breached their fiduciary duties to plaintiff by agreeing to an unfair and wrongfully coercive Tender Offer and Merger, which furthers their personal interest.  The Tender Offer is a breach of fiduciary duty because it is coercive.  First, the Tender Offer is not conditioned on a majority of the public shares tendering into the Tender Offer.  Indeed, there is no minimum tender requirement at all.  Thus, the minority stockholders are powerless to defeat the Tender Offer.  Zodnas can simply buy whatever shares are tendered.  Moreover, the Tender Offer can be extended for various reasons in order to wear down the resistance of the minority stockholders and convince them that Novartis and Zodnas will sooner or later get their shares at $31.00 or less.

79.           Second, there is no assurance that non-tendering stockholders will receive the same consideration in a second-step merger.  The Merger Agreement actually contains a reverse majority of the minority condition.  Rather than conditioning Zodnas’s right to buy shares in the Tender Offer on the tender of a majority of the minority shares, the Merger Agreement conditions Zodnas’s obligation to effect the second-step Merger on a majority of the Public Shares having been purchased in the Tender Offer.  Thus, if a majority of the non-Santo Shares are not tendered, the non-tendering shareholders run the risk there will be no merger.  Moreover, Novartis and Zodnas can propose a merger at a lower price subject to a vote of a majority of the Public Shares.  They can also simply wait out the one year Restricted Period and then propose a merger at a price below $31.00 per share.  In short, non-tendering stockholders would face

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substantial risks that they may end up with an even less attractive transaction than the $31.00 Tender Offer.

80.           Third, the terms of the Merger Agreement permit Novartis and Zodnas to acquire shares at lower prices through open-market purchases, subsequent tender offers or other means.  This subjects non-tendering holders to the risk they may end up receiving less for their shares than $31.00 per share.  Moreover, Novartis and Zodnas may “pick off” enough shares on the cheap so as to enable them to obtain 90% of the outstanding common stock and to effect a short-form merger under 8 Del. C. §253.

81.           Fourth, Novartis is not required to maintain the registration of Eon’s common stock.  Indeed, Novartis’s ability to engage in open market purchases and other transactions in Eon stock following the Tender Offer carries with it the opportunity to render Eon unable to meet registration and listing requirements.

82.           The Tender Offer is not truly voluntary because the public stockholders are being induced to tender their shares for reasons unrelated to the merits of the transaction.  If they choose not to tender into the Tender Offer, public stockholders face the prospect of holding an illiquid stock, subject to Novartis’s option to cash them out at a time and price and in a manner largely of Novartis’s choosing.

83.           Because the Tender Offer is coercive, Novartis and Zodnas are required to demonstrate that the Tender Offer is entirely fair to plaintiff and the Class.  As explained herein, the Tender Offer and Merger and not entirely fair, both as to process and price.

84.           Plaintiff has no adequate remedy at law.

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COUNT II

Breach of Fiduciary Duty
(February 2005 Option Grants and Employment Agreements)

85.           Plaintiff repeats and realleges the preceding paragraphs as if fully set forth herein.

86.           Defendants Karp and Patterson comprise both the Options Committee and the Special Committee.  At the time Karp and Patterson approved the February 2005 Option Grants, they were aware of Eon’s fourth quarter 2004 and year-end financial results.  At the time Karp and Patterson approved the February 2005 Option Grants, they knew that Zodnas and Novartis would be entering into agreements to purchase the Controlling Shares and to acquire the outstanding public shares of Eon at a price higher than the closing market price of Eon common stock.

87.           The Individual Defendants knew that the impending announcement of the Tender Offer would cap the market price for Eon’s public shares, thus reducing and most likely eliminating any spread between the market price of Eon common stock and the Tender Offer price.

88.           The Individual Defendants, and in particular Karp and Patterson, purposefully and intentionally timed the awarding of the February Option Grants to themselves and Eon executives and employees to take advantage of their inside knowledge of Eon’s positive financial results and the impending announcement of the Merger Agreement and Tender Offer.  The Individual Defendants purposefully and intentionally deviated from past practice by awarding stock options to themselves and other insiders prior to the announcement of Eon’s fourth quarter and year-end earnings.  By virtue of this wrongful conduct, and in violation of their fiduciary duties of loyalty, care and good faith, the Individual Defendants transferred value from Eon’s public stockholders to themselves and management.

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89.           At the time the Individual Defendants caused Eon to enter into employment agreements and amended and restated employment agreements with Messrs. Della Fera, Kumar Upadhye, Hampl, Bauer, Eversgerd, Gransee, Bhattacharyya and Ms. Ciganek on February 11, 2005, they knew of the impending agreement of Novartis to acquire the Controlling Shares and that the Company and Novartis would be entering into the Merger Agreement.  In breach of their duties of loyalty, care and good faith, the Individual Defendants entered into the employment agreements with management, providing each of them with lucrative change of control severance provisions.  As a result of these agreements, the Individual Defendants caused a transfer of value that belongs to Eon’s public stockholders.

90.           Plaintiff has no adequate remedy at law.

COUNT III

Breach of Fiduciary Duty and Breach of Contract
(Improper Disenfranchisement and Violation of the Certificate)

91.           Plaintiff repeats and realleges the preceding paragraphs as if fully set forth herein.

92.           Articles Fifth, Seventh and Eleventh have appeared in the Eon Certificate since the time that Eon began publicly trading on the NASDAQ National Market in May 2002.

93.           Eon represented in an Form S I/A filed with the SEC on May 16, 2002, that the provisions in the Eon Certificate were intended to, inter alia, “enhance the likelihood of continuity and stability to the composition of our board of directors.”

94.           The Eon Certificate is a contract between Eon and its stockholders.

95.            The Defendants, in breach of their fiduciary duties and the terms of the Eon Certificate, have inequitably disenfranchised the Eon stockholders by contractually abrogating Articles Fifth and Seventh of the Eon Certificate through the provisions of Section 1.3 of the Merger Agreement.  Section 1.3 of the Merger Agreement contractually obligates the Company

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to replace Eon’s directors with Novartis’s designees.  This includes directors whose terms are not scheduled to expire until 2006.  Rather than fulfilling their fiduciary obligations to the Company and the Class, the Defendants have simply agreed to hand over the reins to Novartis and its designees even before Novartis actually purchases any public shares in the Tender Offer and before Novartis consummates a second-step merger.

96.           Rather than “enhance the likelihood of continuity and stability” of the board, the Individual Defendants have abrogated the certificate provisions intended to have that effect.  This conduct is purposefully designed to impede and disenfranchise the Eon public stockholders.  Defendants do not possess a compelling justification for their actions.

97            Plaintiff has no adequate remedy at law.

COUNT IV

Breach of Fiduciary Duty
(Novartis and Zodnas)

98.            Plaintiff repeats and realleges the preceding paragraphs as if fully set forth herein.

99.            No later than the closing of the purchase of the Santo Shares, Novartis and Zodnas will owe a fiduciary duty, including an obligation of entire fairness, with respect to their further acquisitions of publicly held Eon stock.  Novartis and Zodnas will breach their duty by effecting purchases of such stock through an unfair process and at an unfair price.

COUNT V

Aiding and Abetting

(Novartis, Zodnas and Santo)

100.         Plaintiff repeats and realleges the preceding paragraphs as if fully set forth herein.

101.         Each of the actions constituting inequitable conduct by the Individual Defendants complained of herein was known by Novartis, Zodnas and Santo at the time such conduct occurred to constitute a breach of fiduciary duty.

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102.         Novartis and Zodnas, with the encouragement and/or acquiescence of Santo, knowingly participated in and demanded that the Individual Defendants take such foregoing actions to allow Novartis and Zodnas to acquire complete and unimpeded dominion and control of Eon to the detriment of plaintiff and the Class.

103.         Each of the foregoing breaches of fiduciary duty have caused damage to plaintiffs and the Class.

104.         Plaintiff and the Class have no adequate remedy at law.

WHEREFORE, plaintiff demands judgment and preliminary and permanent relief, including injunctive relief, in his favor and in favor of the Class and against defendants as follows:

A.            Declaring that this action is properly maintainable as a class action;

B.            Declaring and decreeing that the Merger Agreement was entered into in breach of the fiduciary duties of the Individual Defendants and is therefore unlawful and unenforceable;

C.            Enjoining defendants from proceeding with the Tender Offer and Merger;

D.            To the extent the transaction is consummated, rescinding it or awarding rescissory damages to the Class;

E.             Rescinding and invalidating the February 2005 Option Grants and the amended employment agreements and requiring defendants to disgorge any profits received therefrom;

F.             Directing defendants to account to the plaintiff and the Class for all damages suffered by them as a result of defendants, wrongful conduct;

G.            Awarding plaintiff the costs and disbursements of this action, including reasonable attorneys’ and experts, fees;

H.            Granting such other and further relief as this Court may deem just and proper.

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		PRICKETT, JONES & ELLIOTT, P.A.
	By:	/s/ Paul Fioravanti
		Michael Hanrahan (DE Bar No. 941)
		Gary F. Traynor (DE Bar No. 2131)
		Paul Fioravanti (DE Bar No. 3808)
		1310 King Street
		Wilmington, Delaware 19801
OF COUNSEL:		(302) 888-6500
		Attorneys for Plaintiff
Marc A. Topaz
Sandra G. Smith
SCHIFFRIN & BARROWAY, LLP
280 Kind of Prussia Road
Radnor, Pennsylvania 19807
(610) 667-7706
Dated: March 1, 2005

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EX-99.(A)(6)(H)

Exhibit (a)(6)(H)

EFiled: Mar 3 2005 12:12PM EST

Filing ID 5261088

[SEAL]

IN THE COURT OF CHANCERY OF THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

	X
JASON HUNG,	:
	:	C.A. No. 1139-N
Plaintiff,	:
v.	:
	:
EON LABS, INC., NOVARTIS AG,	:
THOMAS STRUNGMANN, BERNHARD	:
HAMPL, MARK R. PATTERSON,	:
FRANK F. BEELITZ, and	:
DOUGLAS M. KARP,	:
	:
Defendants.	:
	X

CLASS ACTION COMPLAINT

Plaintiff, by his attorneys, alleges upon information and belief, except as to the allegations that pertain to plaintiff, which are alleged upon personal knowledge, as follows:

SUMMARY OF THE ACTION

1.This is a stockholders’ class action on behalf of the public stockholders of Eon Labs, Inc. common stock (“Eon” or the “Company”) to enjoin the proposed acquisition of the publicly owned shares of Eon’s common stock by Novartis AG (“Novartis”) as detailed herein (the “Proposed Transaction”).

PARTIES

2Plaintiff has been the owner of common stock of the Company since prior to the announcement of transaction herein complained of, and at all times continuously to date. As of the date of the filing of this action, plaintiff owned 38,000 shares of Eon common stock.

3.Eon is a corporation duly organized and existing under the laws of the State of Delaware with its principal place of business at 1999 Marcus Avenue, Lake Success, New York, 11042. Eon is one of the largest suppliers of generic pharmaceuticals manufacturers in the United States employing approximately 500 people. Eon produces a broad range of pharmaceuticals in a wide variety of therapeutic categories. In 2004, Eon reported record sales of $ 431 million, an increase of 31% from 2003.

4.Headquartered in Basel, Switzerland, Defendant Novartis is Europe’s fourth largest pharmaceutical company. In 2004, Novartis had achieved sales of $ 28.2 billion and a net income of $ 5.8 billion. Novartis companies employ about 81,400 people and operate in over 140 countries around the world. Novartis through its proposed purchase of privately owned Hexal AG will own approximately 67.7% of the equity of Eon.

5Defendant Thomas Strungmann (“Strungmann”) is and was at all relevant times the Company’s Chairman of the Board.  Defendant Strungmann and his twin brother, Andreas Strungmann, also co-founded Hexal AG (“Hexal”), a German corporation founded in 1986 which manufactures and sells pharmaceutical products in Germany, and has served as its Co-Chief Executive Officer and Co-President since then. Hexal owns approximately 67.7% of Eon.

6.Defendant Bernhard Hampl (“Hampl”) is and was at all relevant times a director of the Company, as well as the Company’s President and Chief Executive Officer (“CEO”). From May 1995 to October 1995, Dr. Hampl was employed by Hexal to evaluate the possibility of establishing a U.S. subsidiary.

7.Defendants Mark R. Patterson (“Patterson”), Frank F.  Beelitz (“Beelitz”), and Douglas M. Karp (“Karp”) are and were at all relevant times a directors of the Company.

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8.The defendants named in paragraphs 5 through 7, collectively referred to as the “Individual Defendants,” as officers and/or directors of the Company, are in a fiduciary relationship with plaintiff and the other public shareholders of Eon, and owe them the highest obligations of good faith and fair dealing.

9.Defendant Novartis, through its proposed acquisition of Hexal will have a 67.7% ownership interest in Eon. As the Company’s controlling stockholder, Novartis will be in a fiduciary relationship with plaintiff and the other public shareholders of Eon and as such will owe them the highest fiduciary duties of good faith, fair dealing, and full and candid disclosure.

CLASS ACTION ALLEGATIONS

10.Plaintiff brings this action pursuant to Court of Chancery Rule 23, individually and as a class action on behalf of all other stockholders of the Company (except defendants herein and any persons, firm, trust, corporation, or other entity related to or affiliated with them and their successors in interest), who are or will be threatened with injury arising from defendants’ wrongful actions, as more fully described herein (the “Class”).

11.This action is properly maintainable as a class action for the following reasons:

(a)The Class is so numerous that joinder of all members is impracticable.  As of November 8, 2004, there were 88,823,124 shares of the Company’s stock outstanding. There are likely hundreds, if not thousands, of record and beneficial holders of Eon common stock.

(b)There are questions of law and fact which are common to the Class, including, inter alia, the following:

(i)whether defendants have breached their fiduciary duties of undivided loyalty and good faith and fair dealing with respect to plaintiff and the other members of the Class in connection with the transaction;

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(ii)whether the Individual Defendants and Novartis, in connection with the transaction, are pursuing a course of conduct designed to eliminate the public shareholders of Eon in violation of their fiduciary obligations;

(iii)whether Eon’s directors are able to negotiate at arm’s length and in good faith on behalf of Eon’s minority public shareholders;

(iv)whether Novartis, as the controlling shareholder of Eon, has breached and is breaching its fiduciary duties to the Eon shareholders by making an unfair and inadequate offer to take the Company private;

(v)whether defendants have breached any of their other fiduciary duties to plaintiff and the other members of the Class in connection with the transaction, including the duties of candor, good faith, honesty and fair dealing; and

(vi)whether plaintiff and the other members of the Class would suffer irreparable injury were the transaction complained of herein consummated.

(c)Plaintiff is committed to prosecuting this action and has retained competent counsel experienced in litigation of this nature. Plaintiff’s claims are typical of the claims of the other members of the Class and the Plaintiff has the same interests as the other members of the Class. Accordingly, Plaintiff is an adequate representative of the Class and will fairly and adequately protect the interests of the Class.

(d)The prosecution of separate actions by individual members of the Class would create the risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for defendants, or adjudications with respect to individual members of the Class which would as a practical matter be dispositive of the

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interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interests.

(e)Defendants have acted, or refused to act, on grounds generally applicable to, and causing injury to, the Class and, therefore, preliminary and final injunctive relief on behalf of the Class as a whole is entirely appropriate.

BACKGROUND

12.Headquartered in Holzkirchen, Germany, Hexal is a privately-held pharmaceutical company which develops, produces, markets and distributes modern generic drugs and medicinal products.  Hexal was founded in 1986 by Strungman and his twin brother Andreas Strungmann. Hexal ranks as the second largest manufacturer in the German generics market and the fourth largest generic manufacturer worldwide, employing approximately 7,000 people over 40 countries. Hexal achieved sales of $ 1.65 billion in 2004.

13.In 1995, Hexal bought 50% of the publicly traded shares of Eon. Over time Hexal has increased its stake. Presently, defendant Strungmann and his twin brother Andreas and their families hold a 67.7% stake in Eon Labs through a holding company.(1)

14.Hexal, controlled by Defendant Strungmann, does significant business with Eon. In 2003, the Company had net sales of $0.9 million of products to subsidiaries of Hexal. The Company purchased products and supplies from Hexal and its subsidiaries in the aggregate of $1.0 million in

(1)The holding company, Santo Holding (Deutschland) AG, (“Santo”) is a privately held entity that owns 60,000,000 shares of Eon common stock, representing approximately 67.6% of the company’s outstanding common stock. Defendant Strüngmann, the Chairman of the Company’s Board of Directors and the Co-Chief Executive Officer and Co-President of Hexal AG, is an indirect significant stockholder and director of Santo. Defendant Strüngmann is an indirect significant stockholder and member of the board of directors of Hexal AG, a privately held entity, which owns 137,122 shares of common stock, representing ownership of approximately 0.15%of the Company’s outstanding common stock. As a result, Defendant Dr. Strungmann is the beneficial owner of 60,137,122 shares of common stock, representing ownership of approximately 67.8% of the Company’s outstanding common stock.

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2003. The Company has an agreement with Hexal regarding the drug Cyclosporine. Pursuant to that agreement, the Company has been granted an exclusive and perpetual license to use patented technology from Hexal and pay Hexal a royalty on its sales of Cyclosporine, which was developed using that licensed technology. Pursuant to that agreement’s royalty arrangement, the Company expensed $3.2 million in 2003. In March 2003, the Company memorialized its agreement with Hexal regarding the sale of Cyclosporine products to a third party. Pursuant to that agreement the Company has been granted an exclusive license to use patented technology from Hexal to sell Cyclosporine to the third party outside of the United States. The Company makes royalty payments to Hexal on such sales as described above. The Company also sells the active pharmaceutical ingredient cyclosporine to the third party and retains an administrative fee from such sales, forwarding the remainder to Hexal. Pursuant to this agreement, the Company was obligated to forward $2.7 million to Hexal in connection with such sales made in 2003. In March 2002, the Company entered into a five-year technology agreement with Hexal. Pursuant to that agreement, Hexal cooperates with the Company with respect to the development, manufacture and sale in the United States of, and the sharing of certain information relating to, certain generic pharmaceutical products that Hexal develops. The Company has entered into several underlying product agreements for the rights to several products. The Company expensed $1.3 million in 2003 as provided in the underlying agreements. During 2003, Hexal incurred certain miscellaneous expenses on behalf of the Company totaling $0.1 million, which was reimbursed by the Company.

15.On February 21, 2005, in an attempt to boost its own lagging generic drug business, Novartis announced that it had entered into a definitive merger agreement to acquire 100% ofHexal and Hexal’s 67.7% stake (65.4% fully diluted) in Eon for a total of EUR 5.65 billion in cash or approximately $8.3 billion.

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16.In addition, Novartis will launch a tender offer to acquire the remaining 31.9 million fully diluted shares (34.6%) in Eon Labs for $ 31.00 per share.

17.To facilitate the acquisition of Hexal and control of Eon Labs, Novartis will undertake a series of transactions. Initially, two separate definitive agreements to pay a total of EUR 5.65 (or approximately $ 7.4 billion) billion in cash to acquire 100% of privately-held Hexal, and to acquire 60 million shares of Eon Labs (67.7% of Eon Labs’s share capital and 65.4% on a fully-diluted basis) from Santo.

18.The second step involves a definitive agreement by which Novartis will offer to acquire the remaining approximately 31.9 million fully diluted public shares (treasury method) of Eon for $ 31.00 per share in cash.

19.The transaction has been interpreted as a means to boost sales at Novartis’ Sandoz Generic drug unit, Novartis’ slowest growing division in 2004. For example, Dieter Winet, a portfolio manager at Swisscanto Asset Management has stated “The generics area was a problem for Novartis and with this acquisition they have resolved that problem with a quantum leap.”

20.Both Eon and Hexal will be merged with Novartis’ Sandoz Unit, creating the world’s largest maker of generic pharmaceuticals and medicines based on global revenues. The combined company, which will operate under the Sandoz name will have a combined pro forma 2004 sales of approximately $5.1 billion and a portfolio of more than 600 drugs.

21.Following the consummation of the transaction, Defendant Hampl will serve as Sandoz’s CEO.

22.Contrary to the Company’s portrayal, the transaction actually represents a substantial discount to Eon’s minority public shareholders based on the intrinsic value of the Company and its

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future growth outlook, and is designed to take advantage of Eon’s current trading price without payment of any reasonable premium for the actual value of its assets or its future business prospects.

23.According to estimates, Novartis is paying about 3.8 times Hexal’s and Eon’s combined sales. By comparison, in a similar transaction by Teva Pharmaceuticals (“Teva”) in January 2004, Teva paid approximately 6 times revenue in its purchase of Sicor Inc.

24.Defendant Novartis’ tender offer for the minority shares of Eon is only approximately 11 percent more than Friday’s closing price of Eon shares.

25.Accordingly, the consideration in the transaction is not an industry standard premium at all, nor is it to the best interests of Eon’s minority public stockholders. To the contrary, the consideration in the transaction is woefully inadequate, unfair, and clearly does not represent the true value of the Company.

26.Novartis is intent on paying the lowest possible price to Class members, even though the Individual Defendants and Novartis, as the majority shareholder of Eon, are duty-bound to maximize shareholder value.

27.Novartis has timed the transaction to freeze out Eon’s minority shareholders in order to capture for itself Eon’s future potential without paying an adequate or fair price to the Company’s minority shareholders, to place an artificial lid on the market price of Eon stock so that the market would not reflect the Company’s potential, thereby purporting to justify an unreasonably low price. In fact Novartis notes in the merger announcement on February 21, 2005, that:

Over the past three years alone, Eon Labs has produced 15 first-to-market launches and has positioned itself as the market share leader for nearly half of the products in its portfolio, which includes67 molecules in 147 dosage strengths. Eon Labs currently has 27 ANDAs (Abbreviated New Drug Applications) pending before the US Food and Drug Administration (FDA) covering approximately USD 14.3 billion in annual branded prescription drug sales. The combined pipeline covers nearly all of the major

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molecules predicted to lose patent protection during the next few years, representing an estimated USD 69 billion in US product sales between 2005 and 2009.

28.As noted above, Eon has seen remarkable growth in recent years, which has continued into the present fiscal year, which is not properly valued in the Proposed Transaction. For example, Eon on Oct. 21, 2004 Eon reported net income of $28.1 million for the third quarter ended September 30, 2004, compared to $17.8 million in the comparable quarter in 2003, an increase of 57.6%. For the nine months ended September 30, 2004, net income was $89.2 million, compared to $51.0 million in the comparable period in 2003, an increase of 75.0%. On July 22, 2004, Eon reported net income of $28.8 million for the second quarter ended June 30, 2004, compared to $18.0 million in the comparable quarter in 2003, an increase of 59.6%. For the six months ended June 30, 2004, net income was $61.1 million, compared to $33.1 million in the comparable period in 2003, an increase of 84.4%. Moreover, on April 22, 2004, Eon reported record net income of $32.3 million for the first quarter ended March 31, 2004, compared to $15.1 million in the comparable quarter in 2003, an increase of 113.9%.

29.Furthermore, in conjunction with the merger announcement on February 21, 2005, Eon announced preliminary financial results for the fourth quarter and year end December 31, 2004 of approximately $30.2 million (net income) for the fourth quarter ended December 31, 2004. This represents an increase of 57.3% compared to the comparable quarter in 2003 of approximately $19.2 million. Diluted earnings per share if expected to be $0.33 for the fourth quarter ended December 31, 2004, compared to $0.21 for the comparable quarter in 2003, representing an increase of 57.1%. Moreover, Eon expects net income for the year ended December 31, 2004 to be $119.4 million, compared to $70.1 million in the comparable period in 2003, an increase of 70.2%.

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30.In contrast, Novartis’ net income in the fourth quarter rose 1%, the slowest profit growth for Novartis in five quarters.

31.The consideration to be paid to Class members in the transaction is unfair and grossly inadequate because, among other things, the intrinsic value of Eon’s common stock is materially in excess of the amount offered for those securities in the proposed acquisition given the stock’s current trading price and the Company’s prospects for future growth and earnings.

32.Novartis timed its offer to take advantage of the decline in the market price of Eon’s stock. The offer has the effect of capping the market for Eon’s stock to facilitate Novartis’ plan to obtain the public interest in Eon as cheaply as possible.

33.Under the circumstances, the Individual Defendants are obligated to explore all alternatives to maximize shareholder value.

34.The defendants have breached their duty of loyalty to Eon stockholders by using their control of Eon to force plaintiff and the Class to sell their equity interest in Eon at an unfair price, and deprive Eon’s public shareholders of maximum value to which they are entitled. The Individual Defendants have also breached the duties of loyalty and due care by not taking adequate measures to ensure that the interests of Eon’s public shareholders are properly protected from overreaching. Eon has breached its fiduciary duties, which arise from its control of Eon, by using its control for its own benefit.

35.The terms of the transaction are grossly unfair to the Class, and the unfairness is compounded by the gross disparity between the knowledge and information possessed by defendants by virtue of their positions of control of Eon and that possessed by Eon’s public shareholders. Defendants’ scheme and intent is to take advantage of this disparity and to induce the Class to

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relinquish their shares in the acquisition at an unfair price on the basis of incomplete or inadequate information.

36.Unless enjoined by this Court, the defendants will continue to breach their fiduciary duties owed to plaintiff and the Class and will consummate the Proposed Transaction to the irreparable harm of plaintiff and the Class.

37.Plaintiff and the other members of the Class have no adequate remedy at law.

PRAYER FOR RELIEF

WHEREFORE, plaintiff demands judgment and preliminary and permanent relief, including injunctive relief, in his favor and in favor of the Class and against defendants as follows:

A.Declaring that this action is properly maintainable as a class action;

B.Enjoining defendants, their agents, counsel, employees and all persons acting in concert with them from consummating the Proposed Acquisition;

C.To the extent the Proposed Acquisition is consummated, rescinding it or awarding rescissory damages to the Class;

D.Directing defendants to account to the plaintiff and the Class for all damages suffered by them as a result of defendants’ wrongful conduct;

E.Awarding plaintiff the costs and disbursements of this action, including reasonable attorneys’ and experts’ fees; and

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F.Granting such other and further relief as this Court may deem just and proper.

Dated: March 3, 2005

	ROSENTHAL, MONHAIT, GROSS & GODDESS, P.A.
	By:	/s/ Carmella P. Keener
	Carmella P. Keener (DSBA No. 2810)
	919 North Market Street, Suite 1401
	P.O. Box 1070
	Wilmington, Delaware 19899
	(302) 656-4433
	Attorneys for Plaintiff
OF COUNSEL:
FARUQI & FARUQI, LLP
320 East 39th Street
New York, New York 10016
(212) 983-9330

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