SC 14D9/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

SCHEDULE 14D-9

(RULE 14d-101)

SOLICITATION/RECOMMENDATION STATEMENT
UNDER SECTION 14(d)(4) OF THE
SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 15)

VENTANA MEDICAL SYSTEMS, INC.
(Name of Subject Company)

VENTANA MEDICAL SYSTEMS, INC.
(Name of Person Filing Statement)

Common Stock, Par Value $0.001 Per Share

(Title of Class of Securities)

92276H106

(CUSIP Number of Class of Securities)

Christopher M. Gleeson

President and Chief Executive Officer

VENTANA MEDICAL SYSTEMS, INC.

1910 E. Innovation Park Dr.

Tucson, AZ 85755

Telephone (520) 887-2155

Toll Free (800) 227-2155

Fax (520) 229-4207

(Name, Address and Telephone Number of Person Authorized to Receive

Notices and Communications on Behalf of the Person Filing Statement)

COPIES TO:

Thomas A. Cole	Daniel M. Mahoney
Fredrick C. Lowinger	Snell & Wilmer L.L.P.
Michael A. Gordon	One Arizona Center
Robert L. Verigan	400 E. Van Buren
Sidley Austin LLP	Phoenix, AZ 85004
1 South Dearborn Street	Telephone (602) 382-6000
Chicago, IL 60603	Fax (602) 382-6070
Telephone (312) 853-7000
Fax (312) 853-7036

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

The purpose of this amendment (this “Amendment”) is to amend and supplement or restate, as applicable, the information set forth in Items 1-4 and Items 6-9 of the Solicitation/Recommendation Statement on Schedule 14D-9 filed by Ventana Medical Systems, Inc., a Delaware corporation (the “Company” or “Ventana”), on July 11, 2007 (as amended, including pursuant to this Amendment, this “Schedule 14D-9”).

Item 1.   Subject Company Information.

Item 1 is hereby amended by replacing section (b) thereof with the following:

(b) Securities.  The title of the class of equity securities to which this Schedule 14D-9 relates is Ventana’s common stock, par value $0.001 per share (the shares of the common stock being referred to as the “Shares”), and any associated preferred stock purchase rights (the “Rights”) issued pursuant to the Rights Agreement, dated as of May 6, 1998 (as amended from time to time, the “Rights Agreement”), between Ventana and Wells Fargo Bank, N.A. (as successor to Norwest Bank Minnesota, N.A.), as rights agent. Unless the context requires otherwise, all references to the Shares include the Rights, and all references to the Rights include the benefits that may inure to the holders of the Rights pursuant to the Rights Agreement. As of January 20, 2008, there were 34,844,346 Shares outstanding and an additional 7,506,064 Shares reserved for issuance under the Company’s equity compensation plans, including 4,895,184 Shares issuable upon the exercise of outstanding stock options granted pursuant to those equity compensation plans.

Item 2.   Identity and Background of Filing Person.

Item 2 is hereby amended by replacing section (b) thereof with the following:

(b) Tender Offer.  This Schedule 14D-9 relates to the tender offer by Rocket Acquisition Corporation, a Delaware corporation (“Purchaser”) and an indirect wholly-owned subsidiary of Roche (as defined below), pursuant to which Purchaser offered to buy all outstanding Shares for $75.00 per Share, net to the seller in cash, upon the terms and subject to the conditions set forth in the Offer to Purchase dated June 27, 2007 and the related Letter of Transmittal (which, together with any amendments or supplements thereto made prior to the execution of the Merger Agreement (as defined below), collectively constitute the “Initial Offer;” the Initial Offer, together with any amendments or supplements thereto, including pursuant to the Merger Agreement, collectively constitute the “Offer”). The Initial Offer is described in a Tender Offer Statement on Schedule TO, filed with the United States Securities and Exchange Commission (the “SEC”) on June 27, 2007 by Roche Holding Ltd, a joint stock company organized under the laws of Switzerland (“Roche”), and Purchaser.

The Schedule TO indicates that the Initial Offer is the first step in Purchaser’s plan to acquire all of the outstanding Shares. Purchaser intends, as soon as practicable after consummation of the Initial Offer, to seek to have Ventana complete a second-step merger with Purchaser. Pursuant to the terms of the second-step merger, each remaining Share (other than Shares held by Company, any subsidiary of the Company, Holdings, any subsidiary of Holdings or any stockholder who properly perfects appraisal rights under the Delaware General Corporation Law (the “DGCL”)), would be converted into the right to receive an amount in cash per Share equal to the price per Share paid in the Initial Offer.

On January 21, 2008, Ventana, Roche Holdings, Inc., a Delaware corporation (“Holdings”), and Purchaser entered into an agreement and plan of merger (the “Merger Agreement”). Under the Merger Agreement, Purchaser agreed to amend the terms and conditions of the Initial Offer by (a) increasing the price to be paid per Share from $75.00, as provided in the Initial Offer, to $89.50 per Share and (b) amending certain terms and conditions of the Initial Offer (the Initial Offer, as so amended pursuant to the Merger Agreement, the “Revised Offer”). On January 22, 2008, Roche and Purchaser filed with the SEC Amendment No. 17 to their Tender Offer Statement on Schedule TO reflecting the terms of the Revised Offer, and on January 25, 2008, Roche and Purchaser filed an amended and restated offer to purchase reflecting the Revised Offer as Exhibit (a)(l)(viii) to Amendment No. 18 to their Tender Offer Statement on Schedule TO.

The Revised Offer is being made pursuant to the Merger Agreement. The Merger Agreement provides that, following consummation of the Revised Offer and subject to the terms and conditions contained in the

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Merger Agreement, including, if required by law, obtaining the necessary vote of the Company’s stockholders in favor of the adoption of the Merger Agreement, Purchaser will be merged with and into the Company (the “Merger”), and each outstanding Share (other than Shares held by the Company, any subsidiary of the Company, Holdings, any subsidiary of Holdings (including Purchaser) or any Company stockholder who properly perfects appraisal rights under the DGCL) will be converted into the right to receive an amount in cash equal to $89.50, net to the seller in cash (the “Merger Consideration”). Notwithstanding the foregoing, in the event that Holdings, Purchaser or any other subsidiary of Holdings acquires at least 90% of the outstanding Shares pursuant to the Revised Offer and the Merger may be effected pursuant to Section 253 of the DGCL, the parties to the Merger Agreement have agreed to take all necessary and appropriate action to cause the Merger to become effected without a meeting of Company stockholders, in accordance with the DGCL, as soon as practicable following the date on which Shares are first accepted for payment (the “Acceptance Date”).

Following the consummation of the Merger, the Company will continue as the surviving corporation (the Company, as the surviving corporation after the Merger, the “Surviving Corporation”) and will be a wholly owned subsidiary of Holdings. A copy of the Merger Agreement is filed as Exhibit (e)(16) to this Amendment and is incorporated by reference herein.

Pursuant to the Merger Agreement, February 7, 2008 has been set as the initial expiration date of the Revised Offer, subject to extension in certain limited circumstances as required under the Merger Agreement. Following the expiration of the Offer, Purchaser is required to, if requested by the Company, or may, in its sole discretion, make available a subsequent offering period of not less than three business days after the expiration of the Revised Offer. The Company has not yet determined whether it expects to require Purchaser to provide a subsequent offering period.

According to the Tender Offer Statement on Schedule TO filed by Roche and Purchaser on June 27, 2007, as amended, the business address of Purchaser is 9115 Hague Road, Indianapolis, Indiana 46250; Purchaser’s telephone number is (317) 521-2000; the business address of Roche is Grenzacherstrasse 124, CH-4070 Basel, Switzerland; and Roche’s telephone number is +41-61-688-1111.

Item 3.   Past Contacts, Transactions, Negotiations and Agreements.

Item 3 is hereby amended by replacing subsections (b), (c) and (d) thereof with the following:

(b) Cash Consideration Payable Pursuant to the Revised Offer.

If the directors and executive officers of the Company who own Shares tender their Shares for purchase pursuant to the Revised Offer, they will receive the same cash consideration on the same terms and conditions as the other stockholders of the Company. As of January 20, 2008, the directors and executive officers of the Company were deemed to beneficially own in the aggregate 7,430,789 Shares (including Shares subject to vested equity awards but excluding Shares subject to unvested equity awards). If the directors and executive officers of the Company were to tender all of such Shares for purchase pursuant to the Revised Offer, and those Shares were accepted for purchase and purchased by Purchaser, the directors and executive officers would receive approximately $620,588,480 in cash in the aggregate (net of the exercise price of vested options) for such Shares, subject to applicable income and employment withholding taxes.

(c) The Merger Agreement.

A summary of the Merger Agreement is contained in Item 7 of this Schedule 14D-9. Such summary is incorporated by reference herein and is qualified in its entirety by reference to the Merger Agreement, which is the actual legal document governing the Merger and the parties’ respective rights and obligations with respect thereto. A copy of the Merger Agreement is filed as Exhibit (e)(16) to this Amendment and is incorporated herein by reference. The Merger Agreement has been included to provide investors and security holders with the information regarding its terms and conditions. It is not intended to provide any other factual information about the Company. No representation, warranty, covenant or agreement described in this Schedule 14D-9 or contained in the Merger Agreement is, or should be construed as, a representation or warranty by the Company to any investor or covenant or agreement of the Company with any investor. The

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representations, warranties, covenants and agreements contained in the Merger Agreement are solely for the benefit of the Company, Holdings and Purchaser, may represent an allocation of risk among the parties, may be subject to standards of materiality that differ from those applicable to investors and may be qualified by disclosures among the parties.

The Company’s directors and executive officers have interests in the transactions contemplated by the Merger Agreement that are in addition to their interests as Company stockholders generally.

(i) Accelerated Vesting of Company Stock Options, Performance Units and Restricted Shares. To the extent that the Company’s directors and executive officers hold options to purchase Shares, performance units or restricted Shares, they will be entitled to receive the consideration payable with respect to those securities pursuant to the Merger Agreement. As of January 20, 2008, the Company’s directors and executive officers held options to purchase 2,802,560 Shares, 230,666 of which were not vested and exercisable as of that date, with exercise prices ranging from $8.75 to $51.32 and an aggregate weighted average exercise price of $14.79 per Share. In addition, as of January 20, 2008, the Company’s directors and executive officers held 19,354 performance units, and the Company’s executive officers held 11,000 restricted Shares.

The Merger Agreement provides that, at the effective time of the Merger (the “Effective Time”),

•  each then-outstanding option to purchase Shares, whether or not vested or exercisable, granted under the Company’s equity compensation plans will vest and be cancelled and, in exchange therefor, the Surviving Corporation will pay to each former holder of any such cancelled option a cash amount equal to the number of Shares subject to the option multiplied by the excess, if any, of the Merger Consideration over the per Share exercise price of the option;

•  each then-outstanding performance unit, whether or not vested, granted under the Company’s equity compensation plans will vest and be cancelled and, in exchange therefor, the Surviving Corporation will pay to each former holder of any such cancelled performance unit a cash amount equal to the number of Shares subject to or related to such performance unit multiplied by the Merger Consideration; and

•  each then-outstanding restricted Share granted under the Company’s equity compensation plans will vest (and all restrictions on any such restricted Shares will lapse) and each such restricted Share will be converted into the right to receive the Merger Consideration.

(ii) Exculpation and Indemnification of Directors and Officers. The Company’s charter contains certain provisions permitted under the DGCL relating to the liability of the Company’s directors and officers. These provisions eliminate the Company’s directors’ and officers’ personal liability to the Company or its stockholders for monetary damages resulting from a breach of fiduciary duty other than (a) for any breach of the duty of loyalty to the Company or its stockholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) under Section 174 of the DGCL (which relates to unlawful payment of dividends and unlawful stock purchases or redemptions) and (d) for any transaction from which the director or officer derived an improper personal benefit. The Company’s bylaws also contain provisions that allow the Company to indemnify its directors and officers to the fullest extent permitted by the DGCL.

In addition, the Company has entered into indemnification agreements with its directors and executive officers that obligate it to indemnify such directors and executive officers to the fullest extent permitted by the DGCL. As permitted by its bylaws, the Company also maintains officers’ and directors’ liability insurance which insures against liabilities that officers and directors of the Company may incur in such capacities.

Pursuant to the Merger Agreement, for six years after the Effective Time, unless otherwise required by applicable law, Holdings has agreed to cause the respective charter and bylaws (or equivalent organizational documents) of the Surviving Corporation and each of its subsidiaries to contain provisions regarding limitations on personal liability of directors and indemnification of, and advancement of expenses to, each current and former director, officer, employee or employee benefit plan fiduciary of the Company or any of its subsidiaries (each, an “Indemnified Person”) in respect of acts, omissions or events occurring at or prior to the

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Effective Time that are no less advantageous to the intended beneficiaries than the provisions in effect on the date of the Merger Agreement.

The Merger Agreement also provides that, for six years after the Effective Time, Holdings shall, and shall cause the Surviving Corporation to, indemnify Indemnified Persons in respect of actions, omissions or events occurring at or prior to the Effective Time to the fullest extent provided in the applicable entity’s organizational documents or under applicable law, in each case, as in effect on the date of the Merger Agreement. Holdings is also required to honor and cause the Surviving Corporation to honor all obligations of the Company to each Indemnified Person in respect of acts, omissions or events occurring at or prior to the Effective Time to the fullest extent provided in any indemnification agreements to which the Company or any subsidiary thereof is a party as of the date of the Merger Agreement, in each case, as in effect on the date of the Merger Agreement.

Under the Merger Agreement, Holdings is required to, and is required to cause the Surviving Corporation to, either continue to maintain in effect for six years after the Effective Time the Company’s directors’ and officers’ insurance policies in place as of the date of the Merger Agreement with terms and conditions at least as favorable as the Company’s existing policies or purchase comparable insurance for such six-year period with terms and conditions at least as favorable as those contained in the Company’s existing policies. In the event that equivalent coverage can only be obtained by paying aggregate premiums in excess of 300% of the current annual premium paid by the Company, the Surviving Corporation is only required to obtain the best available coverage for aggregate premiums not in excess of 300% of such amount.

(iii) Employee Matters. Under the Merger Agreement, Holdings, for a period of one year following the Effective Time, is required to provide to all employees of the Company or any of its subsidiaries as of the Effective Time who continue employment with the Surviving Corporation or any of its affiliates (“Continuing Employees”) with compensation and benefits that are in the aggregate substantially equivalent to those provided by the Company and its subsidiaries as in effect immediately prior to the Acceptance Date. Holdings is required to cause the Surviving Corporation to assume and honor all written employment, change of control, severance, retention or termination agreements applicable to any employee of the Company or any of its subsidiaries.

Under the Merger Agreement, Holdings has agreed to provide each Continuing Employee with credit for all service with the Company and its subsidiaries under employee benefit plans or arrangements of Holdings and its affiliates. Also, to the extent Holdings covers Continuing Employees in any welfare benefit plans it or any of its affiliates maintain, Holdings has agreed to waive all pre-existing condition limitations, exclusions and waiting periods with respect to participation and coverage requirements and, for the plan year in which the closing of the transactions contemplated by the Merger Agreement occurs, to credit each Continuing Employee with any co-payments and deductibles paid prior to the commencement of coverage under such plans in satisfying any applicable deductible or out-of-pocket requirements after the commencement of coverage under such plans.

(iv) Retention Pool and Bonus Arrangements. The Merger Agreement provides that Holdings or the Surviving Corporation will establish a retention plan under which officers and other key employees of the Company will be granted subject to vesting requirements promptly following the Effective Time, cash awards having a value in the aggregate of not less than $10,000,000 and not more than $15,000,000. In addition, the Merger Agreement provides for the payment of cash bonuses to officers and other employees of the Company and its subsidiaries in lieu of the annual equity-based compensation awards which the Company would have granted to such officers and employees in February or March of 2008.

(d) Change in Control Agreements.

Consummation of the transactions contemplated by the Merger Agreement will constitute a change in control under the Company’s equity compensation plans. See the excerpt entitled “Compensation Discussion and Analysis — Potential Payments upon Termination or Change-in-Control — Change in Control” from the 2007 Proxy Statement, which is incorporated by reference into this Item 3.

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The Board was aware of these interests and the interests referred to above and considered them, among other matters described in Item 4 below, in approving the Revised Offer, the Merger and the Merger Agreement and in making the recommendations described in Item 4 below.

ITEM 4.   The Solicitation or Recommendation.

Item 4 is hereby amended by replacing subsection (a) thereof with the following:

(a) Solicitation Recommendation.

As more fully described below, at meetings held on January 19 and 21, 2008, the Board carefully considered and reviewed with the Company’s financial and legal advisors the terms and conditions of the Merger Agreement and the transactions contemplated thereby, including the terms and conditions of the Revised Offer and the Merger and the comparative benefits and risks of the Company’s pursuing other strategic alternatives or independently pursuing its strategic plan.

After this consideration and review, the Board (1) determined that the transactions contemplated by the Merger Agreement are advisable, fair to and in the best interests of the Company and its stockholders, (2) approved and adopted the Revised Offer, the Merger and the Merger Agreement in accordance with the DGCL and (3) recommended that Company stockholders tender their Shares pursuant to the Revised Offer and, if adoption is required by applicable law, adopt the Merger Agreement. Accordingly, and for the other reasons described in more detail below, the Board recommends that you ACCEPT the Revised Offer and TENDER your Shares pursuant to the Revised Offer and, if required by applicable law, ADOPT the Merger Agreement.

A copy of a letter to stockholders communicating the Board’s recommendation is filed as Exhibit (a)(29) to this Amendment and is incorporated herein by reference.

Item 4 is hereby further amended and supplemented by adding the following new paragraphs at the end of subsection (b)(i) thereof:

On July 19, 2007, in connection with the release of second quarter earnings, the Company announced that it was strengthening earnings guidance for 2007 and 2008. On July 26, 2007, Roche extended the Initial Offer, setting August 23, 2007 as the new expiration date. That same day, Goldman, Sachs & Co. (“Goldman Sachs”) contacted a third party (“Party A”) to discuss a possible strategic transaction between Party A and the Company.

On July 31, 2007, the Board convened telephonically to discuss the Initial Offer. At the meeting, Mr. Gleeson recommended that the Board establish a subcommittee to facilitate close communication between the Board and the Company’s management and outside advisors regarding the Initial Offer and the exploration of other strategic alternatives. The Board unanimously agreed. The Board appointed Christopher Gleeson, Rod Dammeyer, Mark Miller, John Patience and Jack Schuler to the subcommittee (the “Subcommittee”).

Prior to Roche’s public announcement in late June of its intent to commence the Initial Offer, the Company was contacted by another third party (“Party B”) regarding a possible transaction in the form of an acquisition of the Company or a joint venture between Party B and the Company. The Board agreed that Mr. Gleeson should meet with executives from Party B to discuss a possible transaction. The executives met at the Company’s headquarters in Tucson on August 7, 2007. Subsequently, Party B had additional conversations with the Company but never conveyed a formal proposal.

Throughout the month of August 2007, the Subcommittee had a number of telephonic meetings with the Company’s outside financial and legal advisors to discuss and evaluate financial projections and analyses prepared by management and the outside financial advisors, respectively, and other opportunities to maximize stockholder value. The Subcommittee recommended that management should assemble a series of investor presentations designed to educate the investment community about the Company’s future growth prospects and business opportunities.

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On August 17, 2007, executives at the Company held preliminary discussions with senior management of Party A regarding the future of companion diagnostics and the advanced staining business. A follow-up telephone call between a representative of Goldman Sachs and Party A was held on August 22, 2007. However, a formal proposal to engage in a strategic transaction with the Company was never put forth by Party A.

On August 21, 2007, Roche extended the Initial Offer, setting September 20, 2007 as the new expiration date.

In September 2007, the Subcommittee continued to convene telephonically with management and the Company’s outside financial and legal advisors to discuss the Initial Offer. On September 5, 2007, the Company raised its earnings guidance for 2008 and 2009 and announced the acquisition of Spring BioScience Corporation. On September 19, 2007, Roche extended the Initial Offer, setting November 1, 2007 as the new expiration date.

On October 2, 2007, the Board held an in-person meeting to obtain an update on the Subcommittee’s efforts and to discuss the Company’s operating performance. At the meeting, the Board was joined by the Company’s outside financial, legal and proxy solicitation advisors. The Company’s outside financial advisors reviewed various strategic alternatives available to the Company. The Board discussed the financial implications of these strategic options.

On October 10, 2007, the Board met telephonically to discuss the Company’s operating performance and the status of the Initial Offer. The Board was joined by the Company’s outside financial, legal and proxy solicitation advisors.

On October 17, 2007, a representative of Goldman Sachs received a telephone call from another third party (“Party C”) expressing interest in exploring the possibility of pursuing a strategic transaction with the Company.

On October 22, 2007, the Board met telephonically to discuss the Initial Offer and investor reaction to the Company’s third quarter earnings announcement. The Subcommittee provided an update on the Initial Offer. The Board discussed the potential interest of other third parties. The Company’s outside financial and legal advisors also participated in the telephonic board meeting.

On October 29, 2007, Roche extended the Initial Offer for the fourth time, setting January 17, 2008 as the new expiration date. That same day, the Board met in person to discuss the Initial Offer and certain financial projections prepared by management and the Company’s outside financial advisors. Applying a variety of valuation methodologies, the management presentation valued the Company in the range of $54 to $119 per Share. The Board then discussed the various methodologies and the valuation range. The Company’s outside legal and financial advisors also participated in the discussion.

On November 6, 2007, Dr. Franz Humer, the Chairman of Roche, telephoned Jack Schuler, the Chairman of the Company. Dr. Humer proposed an in-person meeting later that week in New York City. Mr. Schuler advised Dr. Humer that he would discuss the possibility of a meeting with the Board.

Also, on November 6, 2007, the Company’s senior management team traveled to the offices of Party C to discuss the feasibility of a strategic transaction between the two entities.

On November 7, 2007, the Board convened telephonically and authorized Mr. Schuler’s proposed meeting with Dr. Humer. The Board concluded that the interests of the Company and its stockholders were best served by opening a dialogue with Roche at this juncture. The Board also authorized the negotiation, execution and delivery of a confidentiality agreement with Roche, containing customary terms and conditions for transactions of a similar nature.

On November 10, 2007, Dr. Humer and Mr. Schuler had dinner together in New York City. The discussion centered on general industry trends as well as the future of companion diagnostics. At no point did they commence any type of negotiations regarding the price of the Initial Offer. However, at the end of the dinner, Dr. Humer and Mr. Schuler agreed to instruct their respective legal advisors to prepare a confidentiality

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agreement to facilitate due diligence to be conducted by Roche executives. Dr. Humer indicated that Roche intended to initiate a proxy contest at the Company’s 2008 annual meeting of stockholders (the “Annual Meeting”) if the parties could not agree on a negotiated transaction.

On November 12, 2007, legal advisors for Roche and the Company spoke by telephone and exchanged drafts of a confidentiality agreement. The attorneys discussed the timing and nature of the confidential information to be shared following the execution of a mutually acceptable confidentiality agreement. The attorneys also began exploring the possibility of giving the representatives of Roche an opportunity to meet with senior executives of the Company to discuss the Company’s business and operations, including its financial condition, and to conduct additional due diligence on the Company. The Company thereafter invited senior executives from Roche to the Company’s headquarters in Tucson for a management presentation.

On November 13, 2007, Roche and the Company executed a confidentiality agreement which the Company announced after the close of market trading that day. The agreement allowed Roche to commence due diligence and have appropriate access to non-public information in order for Roche to better understand the Company’s business prospects and the inherent value in companion diagnostics.

On November 14, 2007, executives from Roche arrived in Tucson and participated in a management presentation followed by a question and answer session. The discussions extended into the following day.

On November 16, 2007, the outside legal advisors for the Company and Roche conferred to discuss certain intellectual property issues including the pending patent and antitrust appellate litigation brought against the Company by CytoLogix, Inc. (the “CytoLogix Litigation”).

On November 18, 2007, Mr. Gleeson and Dr. Severin Schwan, the Chief Executive Officer of Roche Diagnostics, had a telephone conference to discuss certain due diligence requests put forth by Roche. Mr. Gleeson did not agree to provide all of the information requested by Dr. Schwan. However, he commited to granting Roche access to an electronic data room that contained information about the Company’s business operations and financial condition.

On November 20, 2007, Mr. Schuler received an e-mail from Dr. Humer suggesting that they meet in New York City to continue their discussions. Mr. Schuler responded by inviting Dr. Humer to the Company’s headquarters in Tucson. On November 21, 2007, the Company gave Roche access to the electronic data room that included confidential information regarding the Company’s business operations.

On November 27, 2007, Dr. Humer traveled to Tucson to meet with Messrs. Schuler and Gleeson along with other members of the Company’s executive management team. The group discussed a variety of issues pertaining to the Company’s operations, including the companion diagnostics and advanced staining businesses. Mr. Schuler and Dr. Humer held a separate meeting to discuss the consideration offered by Roche in the Initial Offer. During this meeting, Dr. Humer informed Mr. Schuler that Roche was prepared to amend the Initial Offer to increase the price to be paid per Share from $75.00 to $86.00, subject to certain conditions including the satisfactory completion of due diligence, the resolution of the CytoLogix Litigation and a prompt execution of a mutually acceptable merger agreement. Mr. Schuler said that he would advise the full Board of the proposed increase.

Mr. Schuler also expressed his disappointment with the proposed increase to Dr. Humer. Mr. Schuler said that he believed the increase was below what investors would find acceptable. On that day, the closing price of the Company’s stock on The NASDAQ Global Select Market was $88.08 per Share. The following day, Mr. Schuler informed Dr. Humer that he was canceling the impending visit of the Roche due diligence team to the Company’s headquarters. Mr. Schuler also cancelled his plans to meet Dr. Humer in New York the following week.

Also, on November 28, 2007, the Board held a telephonic meeting to obtain an update on Dr. Humer’s November 27 visit to Tucson and to discuss how to proceed with Roche. The Company’s outside legal advisors provided the Board with an overview of the due diligence activities that had been undertaken on

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behalf of Roche. The Board carefully considered the possible increase but concluded that the price being proposed was inadequate, especially when compared with the Company’s recent trading price.

The Board then instructed representatives of its financial advisors, Goldman Sachs and Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”), to contact one of Roche’s financial advisors, Greenhill & Co. (“Greenhill”), to discuss valuation issues. The Board agreed that its financial advisors should prepare a presentation illustrating the results of different valuation methodologies with respect to the Company for the representative of Greenhill.

The Company entered into a confidentiality agreement, dated November 28, 2007, with Party C. Plans were made for executives from Party C to visit the Company’s headquarters the following week.

On November 29, 2007, the Company’s outside financial advisors met with Roche’s financial advisors in New York City. In order to advance discussions, the Company’s outside financial advisors provided Roche’s representatives with a presentation on certain preliminary financial analyses. Roche’s financial advisors responded that they did not agree with the assessment of value but they would discuss the materials presented with their client.

Throughout the months of November and December 2007, the Subcommittee met regularly with senior executives and the Company’s outside financial and legal advisors to discuss the Initial Offer and other developments. The Subcommittee continued to evaluate strategic alternatives that might maximize stockholder value.

On December 4, 2007, senior executives at the Company met with executives from Party C and provided to those executives a management presentation that included confidential information regarding the Company’s business model and financial projections. Senior executives discussed a variety of different transaction structures with Party C.

On December 5, 2007, the Company announced that it had received notification from Roche of its intention to seek the election of directors to the Company’s Board of Directors and to make certain other proposals at the Company’s Annual Meeting. Roche’s legal counsel provided a draft notification to the Company’s outside counsel several weeks prior to the notification date.

On December 11, 2007, the Board held an in-person meeting to discuss the status of discussions with Roche and other matters. The Board conferred about the discussions held during the previous week with Party C and concluded that the transaction structures discussed by management and representatives of Party C were inadequate when compared with the Initial Offer.

At the meeting, the Board discussed valuation issues and considered target price ranges. The Company’s outside financial and legal advisors also participated in the discussion. The Board debated various strategies for approaching Roche. At the conclusion of the meeting, the Board asked a representative of Goldman Sachs to contact a representative of Greenhill to discuss how to proceed.

In mid-December, based on reports of conversations between senior executives of Roche and a representative of Merrill Lynch in Europe, the Company’s Merrill Lynch representative reported to various members of the Subcommittee and Company management that Roche could possibly pay up to $90 per Share but not more.

On December 13, 2007, Mr. Gleeson received a telephone call from a representative of Party C informing him that Party C was not in a position to put forth a proposal that would be as attractive to the Company as the Initial Offer from Roche. Also, that same day, a representative of Goldman Sachs contacted Greenhill and discussed the status of the discussions between the parties in general. The following day, a representative of Goldman Sachs spoke with a representative of Citibank, Roche’s other financial advisor. Based on those conversations, the parties agreed to resume discussion after the holidays.

In late December of 2007, Mr. Schuler and Dr. Humer spoke and agreed to meet on January 4, 2008 in New York City.

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On January 4, 2008, Mr. Schuler met with Dr. Humer. During this meeting, Mr. Schuler indicated that he would support an offer of $105 per Share. Dr. Humer responded that Roche was not willing to increase the Initial Offer above $86 per Share. When Mr. Schuler brought up the impression conveyed by Merrill Lynch that Roche had indicated it might pay $90 per Share, Dr. Humer stated that Roche’s position had not changed and no one at Roche was authorized to speculate about a possible increase above $86 per Share.

On January 5, 2008, the Board convened telephonically to discuss Mr. Schuler’s meeting with Dr. Humer. In order to advance the discussions, Mr. Gleeson proposed to the Board that he contact Dr. Schwan. The Board agreed and asked Mr. Gleeson to travel to Switzerland to meet with Drs. Humer and Schwan the following week. The Board authorized Mr. Gleeson to negotiate an acquisition price in the low $90s.

On January 10, 2008, Mr. Gleeson traveled to Switzerland to meet with Drs. Humer and Schwan. The parties discussed the Company’s business performance and outlook as well as the companion diagnostics market.

Mr. Gleeson informed Drs. Humer and Schwan that he did not think the Board would approve a transaction at $86 per Share. However, Mr. Gleeson said that he believed unanimous Board approval of the sale of the Company to Roche was possible at $95 per Share. He also surmised that a majority of the Board might endorse the transaction if Roche were to offer $92 to $93 per Share. Mr. Gleeson stated that he thought that the Board would consider an offer at or above $90 per Share but would not entertain an offer at less than $90 per Share.

On January 11, 2008, a representative of Goldman Sachs received a telephone call from Greenhill. The representative of Greenhill said that Roche believed that Mr. Gleeson’s meeting had been very productive. The Greenhill executive then informed a representative of Goldman Sachs that if the Board were unwilling to consider the sale of the Company for less than $90 per Share, Roche would proceed to a proxy contest. The Greenhill representative also said that, if the Board were willing to contemplate the sale of the Company for less than $90 a share, Roche would put forth a counter-offer.

On January 12, 2008, the Board convened telephonically to review the current state of discussions. On January 13, 2008, the Board again met telephonically and authorized Mr. Gleeson to contact Dr. Humer and propose amending the Initial Offer so as to increase the purchase price per Share to the low-$90s.

On January 14, 2008, Mr. Gleeson telephoned Dr. Humer regarding such an amendment. Dr. Humer informed Mr. Gleeson that a deal was not possible in the low-$90s. However, Dr. Humer stated that Roche would amend the Initial Offer to include a purchase price very close to $90 per Share. The Board met telephonically later that day to consider whether to respond to Dr. Humer’s statements and authorized the Company’s outside financial advisors to contact the Greenhill representative to discuss the possibility of supporting an offer at a price between $89 and $90 per Share. After the Board meeting, Mr. Gleeson had additional conversations with members of the Subcommittee regarding price.

On January 15, 2008, a representative of Goldman Sachs contacted the Greenhill representative to discuss the possibility of completing a friendly transaction at just below $90 per Share. Mr. Gleeson discussed the status of negotiations with other members of the Subcommittee throughout the day. On January 16, 2008, a representative of Goldman Sachs and the Company’s outside legal advisors held numerous discussions with representatives of Roche regarding the CytoLogix Litigation. Roche inquired about the possibility of the Company settling the litigation prior to Roche putting forth a revised offer of between $86 and $90 per Share.

While those discussions continued, Mr. Gleeson received a telephone call from Dr. Schwan who wanted to confer about the CytoLogix Litigation, the offer price and whether Mr. Gleeson was committed to staying at the Company and effectuating the transition. Mr. Gleeson informed Dr. Schwan of his view that a majority of the Board would approve an offer that was only slightly less than $90 per Share and that the Board would not be willing to enter into a merger agreement with any non-standard conditions including the settlement of the CytoLogix Litigation.

Later in the day, a representative of Goldman Sachs received a telephone call from Greenhill. The Greenhill executive proposed that Roche amend the Initial Offer to increase the price to $89.00 per Share. The

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Goldman Sachs representative consulted with Mr. Gleeson and the Company’s outside legal advisors. Mr. Gleeson advised the Goldman Sachs representative to put forth a counter offer of $89.50 per Share. After consulting with his client, the Greenhill executive told the representative of Goldman Sachs that Roche would be willing to amend the Initial Offer so as to increase the purchase price to $89.50 per Share (the “$89.50 per Share Proposal”). After the close of trading on The NASDAQ Global Select Market, Roche announced that it had extended the Initial Offer for the fifth time, setting March 14, 2008 as the new expiration date.

That evening, the Board convened telephonically to consider a resolution authorizing the Company’s outside legal advisors to commence the negotiation of a definitive merger agreement. The resolution was approved by the affirmative vote of all directors except Mr. Schuler, who voted against the resolution. A draft merger agreement was provided to the Company’s outside legal advisors by Roche’s outside counsel.

On January 17, 2008, Dr. Humer called Mr. Schuler to discuss the $89.50 per Share Proposal. Mr. Schuler informed Dr. Humer that he would not be supporting the sale of the Company to Roche for $89.50 per Share. On January 17 and 18, 2008, the Company and its outside legal advisors negotiated with Roche and its outside legal advisors the terms and conditions of a proposed merger agreement. On January 19, 2008, the Board convened telephonically to review and discuss the terms and conditions of the proposed merger agreement and the status of the negotiations. The Company’s outside legal advisors discussed with the Board its fiduciary duties and reviewed the terms and conditions of, and received guidance from the Board with respect to the open terms of, the proposed merger agreement and related transaction documents, including the terms of the proposed stockholder tender and support agreement that Roche had requested that the Company’s directors and executive officers execute. Messrs. Schuler and Patience indicated that they would not be willing to execute the tender and support agreement. The Company’s financial advisors also discussed a preliminary financial analysis of the $89.50 per Share offer price.

On January 19 and 20, 2008, the Company and its outside legal advisors continued to negotiate with Roche and its outside legal advisors regarding the terms and conditions of the proposed merger agreement and related transaction documents. On January 20, 2008, the Company settled the CytoLogix Litigation.

On January 21, 2008, the Board met in person to consider whether to enter into a definitive merger agreement with Roche. The Company’s outside legal advisors presented a summary of the terms and conditions of the proposed merger agreement and related transaction documents.

At that meeting, representatives of Goldman Sachs and Merrill Lynch discussed certain financial analyses related to the proposed transaction and delivered their respective oral opinions, each of which was subsequently confirmed in writing, that, as of January 21, 2008, based upon and subject to the assumptions, limitations and qualifications set forth therein, the $89.50 per share cash consideration to be received by the holders of the Shares pursuant to the Revised Offer and the Merger was fair from a financial point of view to such holders. Copies of Goldman Sachs’ and Merrill Lynch’s opinions are filed as Exhibits (a)(30) and (a)(31), respectively, to this Amendment. On the last day of trading prior to the announcement of the execution of the Merger Agreement, the Company’s shares closed at $85.33 per Share.

During and following the presentations, the Board posed questions to the Company’s outside financial and legal advisors and engaged in discussion, including in executive session. The Board discussed the fact that it believed no other party would make an offer financially superior to $89.50 per Share including Party A, Party B and Party C. After consideration and review, the Board (1) determined that the Merger Agreement and the transactions contemplated thereby, including the Revised Offer and the Merger, are advisable, fair to and in the best interests of the Company and its stockholders, (2) approved the merger agreement and the transactions contemplated thereby in accordance with the DGCL and (3) recommended that Company stockholders accept the Revised Offer and tender their Shares pursuant to the Offer and adopt the Merger Agreement. For a summary of factors considered by the Board, see the next section of this Schedule 14D-9 entitled “Reasons for the Board’s Recommendation.” The Board also approved an amendment to the Rights Agreement, which renders the Rights Agreement inapplicable to the Merger Agreement and the transactions contemplated thereby and causes the Rights Agreement to expire immediately prior to the Effective Time.

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Mr. Schuler voted against the resolutions described above and indicated that he did not at that time intend to tender Shares held by him pursuant to the Revised Offer. Mr. Patience abstained from the vote and also indicated that he did not at that time intend to tender Shares held by him pursuant to the Revised Offer. Mr. Dammeyer was traveling outside the United States during the discussions but joined the meeting by telephone shortly following the vote on the resolutions described above and indicated that he supported such resolutions. As discussed below, the Board considered the issues raised by Messrs. Schuler and Patience and decided to approve the Merger Agreement and the transactions contemplated thereby, including the Revised Offer and the Merger.

In connection with his determination to vote as a Director against approval of the Merger Agreement and indicate his intention to not tender his Shares in the Revised Offer, Mr. Schuler believed that Roche could pay more, and should pay more, for the Company and provided the following reasons: (i) many “sell side” financial analysts have estimated that the Company’s core business is worth $85 to $90 per Share based on the Company’s 2008 and 2009 financial projections (without taking into consideration the value of the Company’s companion diagnostics franchise); (ii) numerous “sell side” financial analysts have estimated that the value of the Company’s companion diagnostics business exceeds $20 per Share, based on limited data that Mr. Schuler believes understate the actual number of companion diagnostic projects of the Company; (iii) Roche has indicated that the acquisition of the Company is integral to its cancer drug business, causing Mr. Schuler to believe that Roche would pay more if forced to, either as the result of a competitive bid or pressure from Company stockholders; (iv) in addition to the possible cash flows and synergies that will accrue to Roche in Europe from the acquisition of the Company, Mr. Schuler believes that the acquisition of the Company will enable Roche and Genentech to commercially introduce oncology drugs more quickly, which Mr. Schuler believes is of critical significance to Roche because he believes that advancing the launch date of just one important drug by one year may be worth in excess of $1 billion to Roche and Genentech; and (v) Mr. Schuler believes that Roche may benefit from having competitors in the oncology arena solely dependent on Roche for the development of companion diagnostics for their drugs.

In connection with Mr. Patience’s determination to abstain from the vote as a director to approve the Merger Agreement and indicate his intention to not tender his shares in the Revised Offer, Mr. Patience believed that Company stockholders would fare better if the Company remains independent. Mr. Patience provided the following reasons: (i) many “sell side” financial analysts completed sum-of-the-parts analyses of the Company and determined that the Company’s advanced and basic staining businesses should be valued in the high $80s to low $90s per Share (without taking into account the Company’s emerging companion diagnostics business, which those analysts have valued at up to $20 per Share and which Mr. Patience believes could be worth substantially more since tissue-based diagnostics could eventually be used by oncologists to develop therapeutic roadmaps for all cancer patients); and (ii) the Company has a leadership position in the high growth anatomical pathology market thereby providing it with unique growth opportunities in the Company’s existing and adjacent business segments that Mr. Patience believes are not reflected in the Revised Offer.

The Board also approved resolutions authorizing the proper officers of the Company to take all necessary steps to exempt (or ensure the continued exemption of) the Merger Agreement and the transactions contemplated thereby from the requirements of Section 203 of the DGCL that apply or purport to apply to the Offer, the Merger, the Merger Agreement or the transactions contemplated thereby and, to the extent permitted by law, take all necessary steps to exempt (or ensure the continued exemption of) the merger agreement and the transactions contemplated thereby from the requirements of Sections 10-2721 to 10-2727 and Sections 10-2741 to 10-2743 of the Arizona Revised Statutes that apply or purport to apply to the Offer, the merger, the merger agreement or the transactions contemplated thereby.

Late in the evening of January 21, 2008, the Company and affiliates of Roche entered into the Merger Agreement, each of the directors and executive officers of the Company other than Messrs. Schuler and Patience entered into the stockholder tender and support agreement, and the Company and Roche issued a joint press release on the morning of Tuesday, January 22, 2008, announcing the execution of the Merger Agreement, Roche’s intention to amend the Initial Offer and the Board’s recommendation that Company

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stockholders tender their Shares pursuant to the Revised Offer. A copy of the press release is filed as Exhibit (a)(29) to this Schedule 14D-9 and is incorporated herein by reference.

Item 4 is hereby further amended by replacing subsection (b)(ii) thereof with the following:

In approving the Merger Agreement and the transactions contemplated thereby, including the Revised Offer and the Merger, and recommending that all holders of Shares accept the Revised Offer, tender their Shares pursuant to the Revised Offer and adopt the Merger Agreement, the Board consulted with the Company’s management and the Company’s outside financial and legal advisors and took into account numerous factors, including, without limitation, the following:

—   The Possible Future Performance of the Company and Attendant Risks.   The Board believed that the $89.50 per Share Revised Offer reflects much of the long-term value creation potential of the Company’s business plan, value-creation initiatives and marketplace opportunities, without subjecting Company stockholders to any execution risk or risks associated with the industry in which the Company operates, including risks associated with regulatory change. The Board considered the execution risks and the potential impact on financial performance, particularly in 2008 and 2009, associated with management distraction resulting from ongoing activities related to the Offer and the normal product introduction and customer adoption issues with respect to Symphony and other new products, each of which are in early stages of their life cycles. The Company has built and maintained its leadership position in tissue-based cancer diagnostics through innovative research and development initiatives. The Board considered that the Company continues to bring to market a robust pipeline of automated platforms and high value diagnostic tests. The Board also considered the success of the Company’s research and development activities, which have generated product introductions that the Board believes have the potential to drive significant additional value in the future. The Board also discussed whether it believed that the Revised Offer properly compensates the Company for the future potential of the Company’s companion diagnostics business.

—   The Price of the Revised Offer and the Course of Negotiations.  The $89.50 per Share Revised Offer represents a price that is 66% higher than the three-year prior high as of June 25, 2007, the last trading day prior to Roche’s public announcement of the Initial Offer. Since announcing the Initial Offer, Roche extended the Initial Offer five times, and the Company and Roche engaged in extensive discussions regarding the value of the Company for several months. The Board believed that, particularly in light of the absence of competing offers since Roche announced the Initial Offer, it is unlikely that Roche would be willing to pay a higher price for the Company than $89.50 per Share. See also “—Opposition of One Director and Abstention of Another Director and the Reasons Therefor” below.

—   The Premium of the Revised Offer Price over the Initial Offer Price and Historical Trading Price.  The $89.50 per Share Revised Offer represents a 19% increase over the Initial Offer. The $89.50 per Share Revised Offer also represents a premium of 73% to the per Share closing price of the Shares on June 25, 2007, the last trading day prior to Roche’s public announcement of the Initial Offer, and a 66% and 314% premium to the Company’s three-year prior high and low trading prices per Share as of that date of $53.93 and $21.64, respectively. Finally, the $89.50 per Share Revised Offer represents a premium of 5% to the closing price of the Shares on January 18, 2008, the last trading day prior to the announcement of the execution of the Merger Agreement.

—   Responses to Efforts to Solicit Competing Offers and Absence of Unsolicited Competing Offers Since the Commencement of the Initial Offer.  After a careful review of the Initial Offer, the Board contacted several potential acquirers or strategic partners to determine whether they were interested in exploring the possibility of a potential transaction with the Company. This process yielded a number of discussions, but none resulted in an offer financially superior to the $89.50 per Share Revised Offer. In this regard, the Board believed that there are no more desirable strategic or other transactional alternatives available at this time, noting in particular the length of time that the Initial Offer has been outstanding, the substantial publicity the Initial Offer has received, the absence of any unsolicited competing offers received by the Company in the over six-month period since the

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commencement of the Initial Offer and the fact that none of the Company’s inquiries to potential acquirers or strategic partners led to agreements for an alternative transaction superior to the Revised Offer.

—   Probability of a Contentious Proxy Contest.  The Board considered the fact that if it did not reach a consensual agreement with Roche, it would likely face a contentious proxy contest for control of the Board at the Annual Meeting. In addition, the Board believed that if Roche proceeded to a proxy fight, Roche would probably be successful in obtaining representation on the Board. In addition, the Board discussed whether it would be in a weaker negotiating position should it attempt to negotiate a transaction immediately prior to, or after, Roche successfully elects its nominees to the Board.

—   Opinions of Goldman Sachs and Merrill Lynch.  The Board considered a presentation from Goldman Sachs and Merrill Lynch of their financial analyses. Goldman Sachs and Merrill Lynch each delivered to the Board its respective oral opinion on January 21, 2008, subsequently confirmed in writing, to the effect that, as of such date and based on and subject to the assumptions, procedures, factors, limitations and qualifications set forth therein, the $89.50 per Share price to be received by the holders of Shares in the Revised Offer and the Merger was fair from a financial point of view to such holders. The Goldman Sachs and Merrill Lynch opinions, which are filed as Exhibits (a)(30) and (a)(31), respectively, to this Amendment and are incorporated herein by reference, set forth the procedures followed, assumptions made, matters considered and limitations on the review undertaken by Goldman Sachs and Merrill Lynch in providing their respective opinions. The Board also considered that each of Goldman Sachs and Merrill Lynch will be entitled to receive a significant portion of its fees only upon consummation of the transaction.

The opinions of Goldman Sachs and Merrill Lynch were addressed to the Board in connection with its consideration of the Revised Offer and the Merger and address only the fairness from a financial point of view of the consideration to be received by the holders of Shares pursuant to the Revised Offer and the Merger. These opinions do not constitute a recommendation to any Company stockholder as to whether such stockholder should tender any Shares pursuant to the Revised Offer or any matter related thereto. Company stockholders are encouraged to read such opinions carefully in their entirety.

—   The Historical Performance of the Company.  Over the past twenty years, the Company has established itself as the premier tissue-based cancer diagnostics company through the development of differentiated automated platforms, high value diagnostic tests and integrated patient information management tools. Over the last five years, the Company has made significant investments in its commercial infrastructure, resulting in it having one of the leading commercial organizations in the industry today. The Board also considered the outstanding financial performance of the Company, including the fact that the Company’s revenues and net income have increased from $88 million and $1 million, respectively, for the year ended December 31, 2001 to $238 million and $32 million, respectively, for the year ended December 31, 2006. In addition, the Company has had 27 consecutive quarters of year-over-year quarterly revenue growth.

—   Company Stockholders Will Not Participate in Future Value Creation.  Although the Board believed that the $89.50 per Share Revised Offer reflects some of the synergies likely to result from the transaction, the Board considered that the all-cash consideration to be paid pursuant to the Revised Offer would preclude Company stockholders from being able to share in the benefits of all of the synergies likely to result from the transaction or other potential future value creation. Certain members of the Board did not believe that the Revised Offer reflects any synergies that Roche is to realize from the transaction.

—   Recent Equity Market Performance.  Since the Initial Offer was commenced, there has been a significant decline in the U.S. and other worldwide stock markets. Furthermore, signs that the U.S. economy is headed into a recession have increased as the housing and job market in the U.S. continue to deteriorate.

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—   Terms and Conditions of the Merger Agreement.  The Board considered the terms and conditions of the Merger Agreement. Specifically, the Board noted that the Merger Agreement is unlikely to prevent an acquisition of the Company on terms more favorable to those in the Merger Agreement, because the Merger Agreement permits the Board in certain circumstances to change its recommendation or terminate the Merger Agreement and enter into a binding agreement with respect to a “Superior Proposal” (as defined in the Merger Agreement). However, if the Company determines to accept a Superior Proposal, Holdings has the right to match such Superior Proposal as provided in the Merger Agreement. The Board noted that if, at any time prior to the Acceptance Date, the Company enters into a definitive agreement regarding a Superior Proposal, the Company would be required to pay Holdings a termination fee of $110,000,000.

In addition, the Board noted that, under the Merger Agreement, Company stockholders that tender Shares pursuant to the Revised Offer would promptly receive payment for their Shares.

—   Recommendation of Management and the Reasons Therefor, Considered in the Light of Any Interests That Differ from Those of Other Stockholders.  Management recommended that the Board approve the transactions contemplated by the Merger Agreement. The Board considered management’s recommendation in light of the fact that management has interests in the transactions contemplated by the Merger Agreement that are in addition to their interests as Company stockholders generally, noting, in particular, that the Merger Agreement (a) provides for the accelerated vesting of Company stock options, performance units and restricted Shares, (b) contains provisions relating to the exculpation and indemnification of officers and directors, (c) requires Holdings to provide employees of the Company and its subsidiaries with compensation and benefits that are in the aggregate substantially equivalent to compensation and benefits provided by the Company immediately prior to the Acceptance Date, (d) provides that Holdings or the Surviving Corporation will establish a retention plan under which officers and other key employees of the Company will be granted promptly following the Effective Time cash awards having a value in the aggregate of not less than $10,000,000 and not more than $15,000,000 and (e) provides for the payment, subject to vesting requirements, of cash bonuses to officers and other employees of the Company and its subsidiaries in lieu of the annual equity-based compensation awards which the Company would have granted to such officers and employees in February or March of 2008.

—   Opposition of One Director and Abstention of Another Director and the Reasons Therefor.  The Board considered the view expressed by Jack Schuler that the Company should not be sold at this time unless Roche pays a higher price and the view expressed by John Patience that the Revised Offer does not reflect the full value of the Company’s companion diagnostics business and other potential growth opportunities. However, the Board disagreed with Messrs. Schuler and Patience, noting the opinions provided by Goldman Sachs and Merrill Lynch, the course of negotiations between the Company and Roche, the absence of any competing proposals in the more than six-month period since Roche announced the Initial Offer and the execution risks associated with the Company’s business plan. For additional reasons regarding Mr. Schuler’s opposition and Mr. Patience’s abstention, see “Background of the Offer.”

—   Availability of Dissenters’ Appraisal Rights.  The Board considered that under Delaware law, Company stockholders who believe that $89.50 per Share does not reflect the fair value of their Shares may elect to have the fair value of their Shares judicially determined if such stockholders comply with the provisions of the Delaware General Corporation Law.

—   Other Considerations.  The Board also took into account a number of other considerations in its deliberations concerning the Merger Agreement and the transactions contemplated thereby, including, without limitation, the following:

•  the limited number of stockholders that have a basis in their common stock above $89.50,

•  the limited conditions to Roche’s obligation to complete the Revised Offer or the parties’ obligations to complete the Merger would be satisfied.

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The Board concluded that it is in the best interests of the Company and its stockholders to adopt the Merger Agreement and the transactions contemplated thereby, including the Revised Offer and the Merger.

The foregoing discussion of the information and factors considered by the Board is not meant to be exhaustive, but includes the material information, factors and analyses considered by the Board in reaching its conclusions and recommendations. The members of the Board evaluated the various factors listed above in light of their knowledge of the business, financial condition and prospects of the Company and the advice of the Company’s financial and legal advisors. In view of the variety of factors and amount of information that the Board considered, the Board did not find it practicable to assign relative weights to the foregoing factors. However, the recommendation of the Board was made after considering the totality of the information and factors involved. In addition, individual members of the Board may have given different weight to different factors.

Opinions of the Company’s Financial Advisors

Opinion of Goldman Sachs

Goldman Sachs rendered its opinion to the Board that, as of January 21, 2008 and based upon and subject to the factors and assumptions set forth therein, the $89.50 per Share in cash to be received by the holders of Shares in the Revised Offer and the Merger was fair from a financial point of view to such holders.

The full text of the written opinion of Goldman Sachs, dated January 21, 2008, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Exhibit (a)(30) to this Schedule 14D-9. Goldman Sachs provided its opinion for the information and assistance of the Board in connection with its consideration of the Revised Offer and the Merger. The Goldman Sachs opinion is not a recommendation as to whether or not any holder of Shares should tender such Shares in connection with the Revised Offer or how any holder of Shares should vote with respect to the Merger.

In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:

•  the Tender Offer Statement on Schedule TO, as amended, originally filed on June 27, 2007 by Roche and Purchaser;

•  Schedule 14D-9 originally filed on July 11, 2007 by the Company;

•  annual reports to stockholders and annual reports on Form 10-K of the Company for the five fiscal years ended December 31, 2006;

•  certain interim reports to stockholders and quarterly reports on Form 10-Q of the Company;

•  certain other communications from the Company to its stockholders;

•  certain publicly available research analyst reports for the Company; and

•  certain internal financial analyses and forecasts for the Company prepared by its management.

Goldman Sachs also held discussions with members of the senior management of the Company regarding the past and current business operations, financial condition and future prospects of the Company, including their views of the risks and uncertainties of achieving the internal financial analyses and forecasts for the Company. In addition, Goldman Sachs reviewed the reported price and trading activity for the Shares, compared certain financial and stock market information for the Company with similar information for certain other companies the securities of which are publicly traded, reviewed the financial terms of certain recent business combinations in the healthcare diagnostics industry specifically and in other industries generally and performed such other studies and analyses, and considered such other factors, as it considered appropriate.

Goldman Sachs relied upon the accuracy and completeness of all of the financial, accounting, legal, regulatory, tax and other information provided to, discussed with or reviewed by it and assumed such accuracy and completeness for purposes of rendering the opinion described above. In addition, Goldman Sachs did not

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make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or off-balance-sheet assets and liabilities) of the Company or any of its subsidiaries, nor was any evaluation or appraisal of the assets or liabilities of the Company or any of its subsidiaries furnished to Goldman Sachs. Goldman Sachs’ opinion does not address the underlying business decision of the Company to engage in the transactions contemplated by the Merger Agreement or the relative merits of such transactions as compared to any strategic alternatives that may be available to the Company. Goldman Sachs’ opinion addresses only the fairness from a financial point of view, as of the date of the opinion, of the $89.50 per Share in cash to be received by the holders of Shares in the Revised Offer and the Merger pursuant to the Merger Agreement. Goldman Sachs’ opinion does not express any view on, and does not address, any other term or aspect of the Revised Offer or the Merger or the transactions contemplated by the Merger Agreement, including, without limitation, the fairness of such transactions to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of the Company or Holdings, nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of the Company or Holdings, or class of such persons in connection with the transaction, whether relative to the $89.50 per Share in cash to be received by the holders of Shares in the Revised Offer and the Merger in the transactions or otherwise. Goldman Sachs’ opinion was necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Goldman Sachs as of, January 21, 2008. Goldman Sachs’ opinion was approved by a fairness committee of Goldman Sachs.

Goldman Sachs and its affiliates are engaged in investment banking and financial advisory services, securities trading, investment management, principal investment, financial planning, benefits counseling, risk management, hedging, financing, brokerage activities and other financial and non-financial activities and services for various persons and entities. In the ordinary course of these activities and services, Goldman Sachs and its affiliates may at any time make or hold long or short positions and investments, as well as actively trade or effect transactions, in the equity, debt and other securities (or related derivative securities) and financial instruments (including bank loans and other obligations) of the Company, Holdings and any of their respective affiliates or any currency or commodity that may be involved in the transaction for their own account and for the accounts of their customers. Goldman Sachs has acted as financial advisor to the Board in connection with, and has participated in certain of the negotiations leading to, the transactions contemplated by the Merger Agreement. In addition, Goldman Sachs has provided certain investment banking and other financial services to Holdings and its affiliates from time to time, including having acted as financial advisor to Genentech, Inc., a majority owned subsidiary of Holdings, with respect to its issuance of Senior Notes (aggregate principal amount of $2,000,000,000) in June 2005. Goldman Sachs also may provide investment banking and other financial services to the Company, Holdings and their respective affiliates in the future. In connection with the above-described services, Goldman Sachs has received, and may receive, compensation.

For a description of the compensation payable by the Company to Goldman Sachs in connection with the Revised Offer and the Merger, see “Item 5 — Persons/Assets Retained, Employed, Compensated or Used” of this Schedule 14D-9.

Opinion of Merrill Lynch

The Company retained Merrill Lynch to act as its financial advisor in connection with the transactions contemplated by the Merger Agreement. In connection with that engagement, the Company requested that Merrill Lynch evaluate the fairness, from a financial point of view, of the consideration to be received by the holders of the Shares pursuant to the Revised Offer and the Merger, other than Roche, Rocket Acquisition Corporation and their respective affiliates. At the meeting of the Board on January 21, 2008, Merrill Lynch rendered its oral opinion to the Board, which opinion was subsequently confirmed in writing, that as of January 21, 2008, based upon the assumptions made, matters considered and limits of such review, as set forth in its opinion, the consideration to be received by the holders of the Shares pursuant to the Revised Offer and the Merger was fair from a financial point of view to such holders, other than Roche, Rocket Acquisition Corporation and their respective affiliates.

The full text of Merrill Lynch’s written opinion, which sets forth material information relating to such opinion, including the assumptions made, matters considered and qualifications and limitations on

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the scope of review undertaken by Merrill Lynch, is attached as Exhibit (a)(31) to this Schedule 14D-9 and is incorporated by reference herein. This description of Merrill Lynch’s opinion is qualified in its entirety by reference to, and should be reviewed together with, the full text of the opinion. Company stockholders are urged to read the opinion and consider it carefully.

Merrill Lynch’s opinion is addressed to the Board and addresses only the fairness, from a financial point of view, of the consideration to be received by holders of the Shares in the Revised Offer and the Merger (other than Roche, Rocket Acquisition Corporation and their respective affiliates) as of January 21, 2008. The terms of the proposed transaction, including the consideration to be received by holders of the Shares, were determined through negotiations between the Company and Roche and were not determined or recommended by Merrill Lynch. Merrill Lynch’s opinion does not address the merits of the underlying decision by the Company to engage in the transaction and does not constitute a recommendation to any Company stockholder as to whether such Company stockholder should tender any Shares pursuant to the Revised Offer and how such Company stockholder should vote on the proposed Merger or any matter related thereto.

In arriving at its opinion, Merrill Lynch, among other things:

•  Reviewed certain publicly available business and financial information relating to the Company that it deemed to be relevant;

•  Reviewed certain information, including financial forecasts, relating to the business, earnings, cash flow, assets, liabilities and prospects of the Company furnished to it by the Company;

•  Conducted discussions with members of senior management of the Company concerning the matters described in the two bullet points above;

•  Reviewed the market prices and valuation multiples for the Shares and compared them with those of certain other publicly traded companies that it deemed to be relevant;

•  Reviewed the results of operations of the Company and compared them with those of certain other publicly traded companies that it deemed to be relevant;

•  Compared the proposed financial terms of the Revised Offer and the Merger with the financial terms of certain other transactions that it deemed to be relevant;

•  Participated in certain discussions and negotiations among representatives of the Company and Roche and their financial and legal advisors;

•  Reviewed the Merger Agreement; and

•  Reviewed such other financial studies and analyses and took into account such other matters as it deemed necessary, including its assessment of general economic, market and monetary conditions.

In preparing its opinion, Merrill Lynch assumed and relied on the accuracy and completeness of all information supplied or otherwise made available to it, discussed with or reviewed by or for it, or publicly available, and Merrill Lynch did not assume any responsibility for independently verifying such information or undertake an independent evaluation or appraisal of any of the assets or liabilities of the Company nor was Merrill Lynch furnished with any such evaluation or appraisal, and Merrill Lynch did not evaluate the solvency or fair value of the Company under any state or federal laws relating to bankruptcy, insolvency or similar matters. In addition, Merrill Lynch did not assume any obligation to conduct any physical inspection of the properties or facilities of the Company. With respect to the financial forecast information furnished to or discussed with Merrill Lynch by the Company, Merrill Lynch assumed that they were reasonably prepared and reflected the best currently available estimates and judgment of the Company’s management as to the expected future financial performance of the Company.

Merrill Lynch’s opinion was necessarily based upon market, economic and other conditions as they existed and could be evaluated on the date of the opinion, and upon the information made available to Merrill Lynch as of the date of the opinion. Merrill Lynch has no obligation to update its opinion to take into account

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events occurring after the date that its opinion was delivered to the Board. Circumstances could develop prior to consummation of the Revised Offer or the Merger that, if known at the time Merrill Lynch rendered its opinion, would have altered its opinion.

The Company retained Merrill Lynch, among other reasons, based upon Merrill Lynch’s experience and expertise. Merrill Lynch is an internationally recognized investment banking firm with substantial experience in transactions similar to the proposed transaction. Merrill Lynch, as part of its investment banking business, is continually engaged in the valuation of businesses and securities in connection with business combinations and acquisitions and for other purposes.

Merrill Lynch has, in the past, provided financial advisory and financing services to Roche and its affiliates unrelated to the Revised Offer and the Merger and has received fees for the rendering of such services. In addition, in the ordinary course of its business, Merrill Lynch or its affiliates may actively trade the Shares and other securities of the Company, as well as securities of Roche and its affiliates, for its own account and for the accounts of customers and, accordingly, may at any time hold a long or short position in such securities.

For a description of the compensation payable by the Company to Merrill Lynch in connection with the Revised Offer and the Merger, see “Item 5 — Persons/Assets Retained, Employed, Compensated or Used” of this Schedule 14D-9.

Goldman Sachs’ and Merrill Lynch’s Joint Financial Analyses

The following is a summary of the material financial analyses jointly delivered by Goldman Sachs and Merrill Lynch to the Board in connection with rendering their respective opinions described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs and Merrill Lynch, nor does the order of the analyses described represent relative importance or weight given to those analyses by Goldman Sachs and Merrill Lynch. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Goldman Sachs’ and Merrill Lynch’s financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before January 21, 2008 and is not necessarily indicative of current market conditions.

Historical Stock Trading and Premium Analysis.  Goldman Sachs and Merrill Lynch analyzed the $89.50 per Share consideration to be received by holders of the Shares in relation to the closing price of the Shares as of June 25, 2007 (which was the last trading day prior to public announcement of Roche’s offer) and January 18, 2008, the average closing price of the Shares for the 10-trading day, 20-trading day, 60-trading day and one-year periods ended June 25, 2007 and January 18, 2008, respectively, and the undisturbed 52-week high closing price of the Shares. This analysis indicated that the $89.50 per Share in cash to be received by holders of the Shares in the Revised Offer and the Merger represented a premium to the per Share prices referenced above as set forth in the tables below.

	Period Ended			Period Ended
	June 25,			January 18,
Premium to:	2007			2008
One-day stock price		73.0	%		4.9	%
Average closing price for the 10-trading day period		70.1	%		3.9	%
Average closing price for the 20-trading day period		71.5	%		3.8	%
Average closing price for the 60-trading day period		82.3	%		3.0	%
Average closing price for the one-year period		102.3	%		31.9	%
Undisturbed 52-week high		66.0	%

Implied Transaction Multiples.  Goldman Sachs and Merrill Lynch calculated selected implied transaction multiples for the Company based on the $89.50 to be paid for each Share in the Revised Offer and the Merger. Such multiples were based on estimated earnings before interest, taxes, depreciation and amortization

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(“EBITDA”) and generally accepted accounting principles (“GAAP”) earnings per share (“EPS”) for the Company prepared by the management of the Company. Enterprise Value is defined as market value of equity plus total debt less cash. Goldman Sachs and Merrill Lynch calculated the following transaction multiples implied by the $89.50 to be paid for each Share:

•  the Enterprise Value based on the $89.50 per Share price as a multiple of estimated EBITDA for 2008;

•  the Enterprise Value based on the $89.50 per Share price as a multiple of estimated EBITDA for 2009;

•  the $89.50 per Share price as a multiple of estimated GAAP EPS for 2008; and

•  the $89.50 per Share price as a multiple of estimated GAAP EPS for 2009.

The following table sets forth the multiples referred to above:

		Implied
		Multiples
		at $89.50
EBITDA multiples	2008		25.6	x
	2009		18.7	x
Price to Earnings (P/E) multiples	2008		45.8	x
	2009		32.3	x

Selected Transactions Analysis.  Goldman Sachs and Merrill Lynch analyzed certain information relating to the following selected transactions in the healthcare diagnostics industry. These transactions (listed by target/acquirer and date of announcement) were:

•  Dade Behring Holdings, Inc. / Siemens AG (July 2007)

•  Cholestech Corporation / Inverness Medical Innovations, Inc. (June 2007)

•  Digene Corporation / Qiagen N.V. (June 2007)

•  Cytyc Corporation / Hologic, Inc. (May 2007)

•  Biosite Incorporated / Inverness Medical Innovations, Inc. (April 2007)

•  BioVeris Corporation / Roche (April 2007)

•  Dako A/S / EQT Partners AB (February 2007)

•  Adeza Biomedical Corporation / Cytyc Corporation (February 2007)

•  Vision Systems Limited / Danaher Corporation (October 2006)

•  TriPath Imaging, Inc. / Becton, Dickinson and Co.  (August 2006)

•  Diagnostics Products Corp. / Siemens AG (April 2006)

•  TheraSense, Inc. / Abbott Laboratories (January 2004)

•  i-STAT Corporation / Abbott Laboratories (December 2003)

•  IGEN International, Inc. / Roche (July 2003)

•  Disetronic Holding AG / Roche (February 2003)

For each of the selected transactions, Goldman Sachs and Merrill Lynch calculated the premium represented by the price paid for the target to the average closing price per share of the target one month prior to the announcement date, and the one-year forward sales multiples, EBITDA multiples, earnings before interest and taxes (“EBIT”) multiples and price to earnings multiples. Goldman Sachs and Merrill Lynch relied

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on information from public filings, press releases and other publicly available information. The following table presents the results of this analysis:

Implied

Premium/

Selected Transactions

Multiple at

Range

Mean

Median

$89.50

Premium to average closing price 1 month prior to announcement

19.9% - 148.2%

51.9

%

43.2

%

71.5

%

Sales multiples

3.6x - 9.0

x

5.5

x

5.3

x

8.8

x

EBITDA multiples

15.9x - 51.0

x

27.1

x

19.6

x

25.6

x

EBIT multiples

15.6x - 51.9

x

32.9

x

27.6

x

31.1

x

GAAP P/E multiples

29.0x - 59.2

x

43.2

x

42.7

x

45.8

x

Selected Companies Analysis.  Goldman Sachs and Merrill Lynch reviewed and compared certain financial information for the Company to corresponding financial information, ratios and public market multiples for the following publicly traded corporations in the healthcare diagnostics industry:

•  Abaxis, Inc.

•  Gen-Probe Inc.

•  Immucor Inc.

•  Inverness Medical Innovations, Inc.

•  Quidel Corp.

Although none of the selected companies was directly comparable to the Company, the companies included were chosen because they were publicly traded companies with operations, growth and margin profiles that for purposes of this analysis may be considered similar to certain operations, growth and margin profiles of the Company.

Goldman Sachs and Merrill Lynch also calculated and compared various financial multiples and ratios for the Company and the selected companies based on share prices as of January 18, 2008 and information obtained from SEC filings, estimates provided by the Institutional Brokers’ Estimate System (a data service that compiles estimates issued by securities analysts, “IBES”) and the Company’s management projections.

With respect to the Company and the selected companies, Goldman Sachs and Merrill Lynch calculated the ratios of price to estimated calendar years 2008 and 2009 GAAP EPS (referred to as P/E multiples). The results of these analyses are summarized as follows:

Company-

Company-

Selected Companies

Management

IBES

Range

Mean

Median

Projections

Projections

2008 P/E multiples

20.9x - 45.4

x

31.3

x

28.3

x

45.8

x

45.9

x

2009 P/E multiples

17.3x - 31.7

x

24.5

x

23.0

x

32.3

x

33.9

x

Goldman Sachs and Merrill Lynch also calculated the five-year EPS compound annual growth rate (“5-Year EPS-CAGR”), and the ratios of estimated calendar year 2008 GAAP EPS (“2008 PE”) to the 5-Year EPS-CAGR, for the Company and the selected companies. Such ratios with respect to the Company were calculated utilizing the 5-year EPS-CAGR from both IBES and management projections. The following table presents the results of this analysis:

							Company-		Company-
	Selected Companies						Management		IBES
	Range		Mean		Median		Projections		Projections
5-Year EPS-CAGR		15.0% - 25.0%		21.3%		22.5%		40.4%		22.5%
2008 PE/5-Year EPS-CAGR		1.1x - 2.0x		1.5x		1.4x		1.1x		2.0x

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Present Value of Future Share Price.  Goldman Sachs and Merrill Lynch performed an illustrative future share price analysis, which was designed to provide an indication of the potential future value of the Company’s equity as a function of the Company’s future earnings and its assumed price to 12-month forward EPS multiple. Goldman Sachs and Merrill Lynch calculated implied equity values per Share as of December 31, 2008 by applying P/E multiples ranging from 30.0x to 40.0x to projections prepared by the Company’s management of 2009 GAAP EPS. Goldman Sachs and Merrill Lynch then calculated the present value of the implied per share equity values using discount rates ranging between 10.5% and 12.5% based on estimates relating to the Company’s cost of equity capital. The following table presents the results of this analysis:

Implied Future Share Price	$	83.18 - $110.91
Present Value of Implied Future Share Price	$	73.94 - $100.37

Discounted Cash Flow Analysis.  Goldman Sachs and Merrill Lynch performed an illustrative discounted cash flow analysis on the Company using the Company’s management projections to determine a range of implied present values per Share of the Company. Using discount rates ranging from 10.0% to 12.0% based on estimates relating to the Company’s weighted average cost of capital, terminal multiples of estimated GAAP EPS as of 2011 ranging from 24.0x to 32.0x, and implied price to earnings over growth rate multiples ranging from 1.6x to 2.1x (which range was calculated using a long-term growth rate of 15.0% after calendar year 2011 based on the Company’s management projections), Goldman Sachs and Merrill Lynch derived a range of illustrative present values of $82.11 to $113.05 per Share.

Using the Company’s management projections and a discount rate of 11%, and a terminal multiple of estimated GAAP EPS as of 2011 of 28.0x, Goldman Sachs and Merrill Lynch performed a discounted cash flow analysis to determine a range of implied present values per Share based on sensitivities to Company management’s revenue projections and EBIT margins. In performing the illustrative cash flow sensitivity analysis, Goldman Sachs and Merrill Lynch applied varied sensitivities to Company management’s revenue projections ranging from realization of 80.0% to 100.0% of such projections annually over the forecast period for calendar years 2008 to 2011 and to Company management’s EBIT margin projections ranging from 7.0% below such projections to no adjustment to such margin forecast annually over the forecast period for calendar years 2008 to 2011. This analysis resulted in a range of implied present values of $63.93 to $97.06 per Share.

General — Opinions of Goldman Sachs and Merrill Lynch

The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying each of Goldman Sachs’ and Merrill Lynch’s opinions. In arriving at their fairness determinations, each of Goldman Sachs and Merrill Lynch considered the results of all of their analyses and did not attribute any particular weight to any factor or analysis considered by them. Rather, each of Goldman Sachs and Merrill Lynch made their determination as to fairness on the basis of their experience and professional judgment after considering the results of all of their analyses. No company or transaction used in the above analyses as a comparison is directly comparable to the Company or the contemplated Revised Offer and Merger, nor is an evaluation of such analyses entirely mathematical.

Goldman Sachs and Merrill Lynch prepared these analyses for purposes of providing their respective opinions to the Board as to the fairness from a financial point of view to the holders of Shares of the $89.50 per Share in cash to be received by such holders in the Revised Offer and the Merger. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of the Company, Goldman Sachs, Merrill Lynch or any other person assumes responsibility if future results are materially different from those forecast.

The $89.50 per Share in cash to be paid in connection with the Revised Offer and the Merger was determined through arms’-length negotiations between the Company and Roche and was approved by the

22

Board. Neither Goldman Sachs nor Merrill Lynch recommended any specific amount of consideration to the Company or the Board or that any specific amount of consideration constituted the only appropriate consideration for the Revised Offer or the Merger.

As described above, each of Goldman Sachs’ and Merrill Lynch’s opinions to the Board was one of many factors taken into consideration by the Board in making its determination to approve the Merger Agreement, the Revised Offer and the Merger. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs and Merrill Lynch in connection with their respective fairness opinions and is qualified in its entirety by reference to each of the written opinions of Goldman Sachs and Merrill Lynch, attached as Exhibits (a)(30) and (a)(31), respectively, to this Schedule 14D-9.

Item 4 is hereby further amended by replacing subsection (c) thereof with the following:

(c) Intent to Tender.

To the Company’s knowledge after making reasonable inquiry, all of the Company’s executive officers, directors (other than John Patience and Jack Schuler) and affiliates (other than subsidiaries of the Company) currently intend to tender for purchase pursuant to the Revised Offer all Shares held of record or beneficially owned by them, other than restricted Shares and Shares subject to options. See Item 3 of this Schedule 14D-9 for a summary of the treatment of restricted Shares and Shares subject to options under the Merger Agreement.

The Merger Agreement provides that each Share held by a subsidiary of the Company will be converted into such number of shares of stock of the Surviving Corporation such that each such subsidiary owns the same percentage of the outstanding capital stock of the Surviving Corporation immediately following the Effective Time as such subsidiary owned in the Company immediately prior to the Effective Time.

Item 6.   Interest in Securities of the Subject Company.

Except for scheduled vesting of outstanding option awards, during the past 60 days, no transactions with respect to Shares have been effected by the Company or, to the Company’s best knowledge, by any of its executive officers, directors, affiliates or subsidiaries other than cashless exercises of options by two of its directors, Jack Schuler and John Patience, on January 23, 2008. On that date, Mr. Schuler exercised options to purchase 562,666 Shares and Mr. Patience exercised options to purchase 692,666 Shares.

Item 7.   Purposes of the Transaction and Plans or Proposals.

Item 7 is hereby amended and restated in its entirety as follows:

(a) The Merger Agreement.

The following is a summary of the material provisions of the Merger Agreement and is qualified in its entirety by reference to the full text of the Merger Agreement, a copy of which is filed as exhibit (e)(16) to this Schedule 14D-9, and is incorporated herein by reference. Capitalized terms not otherwise defined herein will have the meanings ascribed thereto in the Merger Agreement.

The Merger Agreement has been filed as an exhibit to this Schedule 14D-9 and this summary of terms is intended solely to provide you with information regarding the terms of the Merger Agreement and is not intended to modify or supplement any factual disclosures about the Company or Roche (or its subsidiaries) in public reports filed with the SEC. In particular, the Merger Agreement and this summary of terms are not intended to be, and should not be relied upon as, disclosures regarding any facts and circumstances relating to the Company or Roche (or its subsidiaries).

The Offer.  The Merger Agreement requires Purchaser to amend the Initial Offer to increase the purchase price to $89.50 per Share, net to the seller in cash, to provide that the conditions will be as set forth in “Conditions of the Offer” below and to amend the expiration date of the Initial Offer and to otherwise conform the terms of the Initial Offer to the requirements of the Merger Agreement. Purchaser expressly reserves the right to waive any of the conditions to the Offer and to make any other changes in the terms of or conditions

23

to the Offer, provided that without the prior consent of the Company (which consent may be granted or withheld by the Company in its sole discretion) (A) the condition that there shall be validly tendered in accordance with the terms of the Offer prior to the expiration date of the Offer and not withdrawn, a number of Shares that, together with the Shares then owned by Purchaser and its Affiliates, represents at least a majority of the total number of Shares outstanding on a fully-diluted basis (the “Minimum Condition”) may not be waived, (B) no change may be made that changes the form of consideration to be paid, decreases the price per Share or the number of Shares sought in the Offer, amends or adds to the conditions to the Offer set forth in “Conditions of the Offer” or amends any other term of the Offer in any manner adverse to the stockholders of the Company and (C) the expiration date of the Offer will not be extended except as otherwise provided in the Merger Agreement.

Extensions of the Offer.  Purchaser will extend the Offer from time to time if at the then-scheduled expiration date of the Offer any of the conditions to the Offer are not satisfied or waived until such conditions are satisfied or waived. In no event will Purchaser be required to extend the Offer beyond May 31, 2008 or, in certain cases, June 30, 2008 (the “End Date”) unless Holdings or Purchaser is not then permitted to terminate the Merger Agreement, in which case Purchaser will be required to extend the Offer beyond the End Date. The Merger Agreement further obligates Purchaser to extend the offer (but not beyond the End Date) for any period required by any rule, regulation, interpretation or position of the SEC or the NASDAQ Global Select Market applicable to the Offer.

The Merger Agreement obligates Purchaser, subject to applicable securities laws and the satisfaction of the conditions set forth in “Conditions of the Offer,” to accept for payment and pay for, as promptly as practicable after the expiration of the Offer, all Shares validly tendered and not withdrawn pursuant to the Offer and validly tendered in the subsequent offering period. The date on which Shares are first accepted for payment pursuant to the Offer is hereinafter referred to as the “Acceptance Date”.

Subsequent Offering Period.  Following expiration of the Offer, Purchaser will, if requested by the Company, or may, in its sole discretion, provide a subsequent offering period in accordance with Rule 14d-11 of the Exchange Act. The Company has not yet determined whether it expects to require Purchaser to provide a subsequent offering period in accordance with Rule 14d-11 of the Exchange Act.

Directors.  The Merger Agreement provides that upon the acceptance for payment of any Shares pursuant to the Offer, Holdings will be entitled to designate the number of directors, rounded up to the next whole number, to the Board that is in the same proportion as the percentage of Shares then beneficially owned by Holdings and its affiliates to the total number of Shares outstanding. The Company is required to use its reasonable best efforts to cause individuals designated by Holdings to be appointed to the Board. The Company will also use its reasonable best efforts to cause individuals designated by Holdings to constitute the number of members, rounded up to the next whole number, on each committee of the Board and the board of directors of each subsidiary of the Company that represents the same percentage as individuals designated by Holdings represent on the Board.

Notwithstanding the foregoing, the Merger Agreement provides that if Holdings exercises its right to appoint directors to the Board, the Board will at all times include at least three Continuing Directors (as defined below) and each committee of the Board and the board of directors of each subsidiary of the Company will at all times include at least one Continuing Director. A “Continuing Director” means a person who is a member of the Board as of the date of the Merger Agreement or is a person selected by the Continuing Directors then in office.

Following the election or appointment of Holdings’ designees to the Board and until the Effective Time, the approval of a majority of the Continuing Directors is required (and such authorization will constitute the authorization of the Board) to authorize:

•  any amendment or termination of the Merger Agreement by the Company;

•  any agreement between the Company and any of its subsidiaries, on the one hand, and Holdings, Purchaser or any of their respective affiliates (other than the Company and its subsidiaries), on the other hand;

24

•  the taking of any action by the Company or any of its subsidiaries that would prevent or materially delay the consummation of the Merger;

•  any extension of the time for performance of obligations or action by Holdings or Purchaser under the Merger Agreement; or

•  any waiver of any of the Company’s rights or remedies under the Merger Agreement.

Top-Up Option.  Pursuant to the Merger Agreement, the Company has granted to Purchaser an option (the “Top-Up Option”) to purchase from the Company up to that number of authorized and unissued Shares that, when added to the number of Shares owned by Purchaser at the time of exercise, constitutes one Share more than 90% of the Shares that would be outstanding immediately after the issuance of all Shares to be issued upon exercise of the Top-Up Option, calculated on a fully-diluted basis. The Top-Up Option may be exercised, in whole or in part, only once, at any time during the 10 business day period following the Acceptance Date, or if any subsequent offering period is provided, during the 10 business day period following the expiration date of such subsequent offering period. The Top-Up Option, however, may not be exercised to the extent:

•  the issuance of the Shares upon exercise of the Top-Up Option would require approval of the Company’s stockholders under the rules and regulations of the NASDAQ Global Select Market; or

•  the number of Shares issuable upon exercise of the Top-Up Option would exceed the number of authorized but unissued and unreserved Shares.

The aggregate purchase price payable for the Shares being purchased by Purchaser pursuant to the Top-Up Option will be payable in cash in an amount equal to the product of the number of Shares to be purchased and the price paid per Share in the Offer.

The Merger.  The Merger Agreement provides that, at the Effective Time, Purchaser will be merged into the Company. At that time, the separate existence of Purchaser will cease, and the Company will be the Surviving Corporation in the Merger.

Under the terms of the Merger Agreement, at the Effective Time, each Share then outstanding will be converted into the right to receive cash equal to the price paid per Share in the Offer, without interest (the “Merger Consideration”). Notwithstanding the foregoing, the Merger Consideration will not be payable in respect of (i) Shares held by the Company as treasury stock, by Holdings or any of its subsidiaries and (ii) Shares owned by Company stockholders who properly demand appraisal in accordance with the DGCL.

The Merger Agreement provides that if, at any time after the Acceptance Date, Holdings and its affiliates own at least 90% of the outstanding Shares, Holdings, Purchaser and the Company will take all necessary and appropriate action to cause the Merger to be effected as soon as practicable without a meeting of stockholders of the Company by way of a short-form merger in accordance with Section 253 of the DGCL.

If, however, approval of the stockholders of the Company is required to adopt the Merger Agreement in accordance with the DGCL, the Company has agreed pursuant to the Merger Agreement that it will, among other things, (i) following the Acceptance Date, promptly prepare and file with the SEC a proxy or information statement in connection with the Merger (the “Company Proxy Statement”), (ii) include in the Company Proxy Statement, except to the extent that the Board has effected or effects an Adverse Recommendation Change (as defined below) prior to the Acceptance Date, the recommendation of the Company Board that holders of Shares vote in favor of the adoption of the Merger Agreement, (iii) use its reasonable best efforts to cause the Company Proxy Statement to be cleared by the SEC and thereafter mailed to its stockholders as promptly as practicable and (iv) cause a meeting of its stockholders to be duly called and held as soon as reasonably practicable after the Acceptance Date for the purpose of voting on the adoption of the Merger Agreement. Pursuant to the Merger Agreement, and in accordance with the DGCL and the Company’s certificate of incorporation, if stockholder approval is required to adopt the Merger Agreement, the approval of the holders of not less than a majority of the outstanding Shares, including the Shares owned by Purchaser, will be required.

25

Stock Options.  The Merger Agreement provides that each option to purchase Shares that is outstanding at the Effective Time, whether or not vested or exercisable, will vest and be canceled, and each holder of an option will be entitled to receive an amount in cash equal to the excess, if any, of the Merger Consideration over the applicable exercise price per Share of such option, multiplied by the number of Shares issuable upon exercise of such option.

Restricted Shares.  The Merger Agreement provides that each restricted Share outstanding at the Effective Time will vest (and all restrictions on the restricted Shares will immediately lapse) and will be converted into the right to receive the Merger Consideration.

Performance Units.  The Merger Agreement provides that each performance unit that is outstanding at the Effective Time, whether or not vested, will vest and be canceled, and each holder of a performance unit will be entitled to receive an amount in cash equal to the Merger Consideration, multiplied by the number of Shares subject to the performance unit.

Employee Stock Purchase Plan.  The Merger Agreement provides that Company will suspend payroll deductions and cause the exercise of each outstanding purchase right under the Company’s 2005 employee stock purchase plan not later than the initial scheduled expiration of the Offer.

Representations and Warranties.  In the Merger Agreement, the Company has made customary representations and warranties to Holdings, including representations relating to its corporate existence and power, corporate authorization, governmental authorization, non-contravention, capitalization, subsidiaries, SEC filings, financial statements, disclosure documents, absence of certain changes, absence of undisclosed liabilities, compliance with laws and court orders, litigation, taxes, labor and employment matters, employee benefit plans, environmental matters, material contracts, intellectual property, finders’ fees, the opinions of the Company’s financial advisors and anti-takeover statutes and the Rights Agreement. Holdings has made customary representations and warranties to the Company, including representations relating to its corporate existence and power, corporate authorization, governmental authorization, non-contravention, disclosure documents, finders’ fees, financing and operations of Purchaser.

The representations and warranties in the Merger Agreement will not survive the Acceptance Date.

The representations and warranties have been negotiated with the principal purpose of establishing the circumstances in which Purchaser may have the right not to consummate the Offer or a party may have the right to terminate the Merger Agreement, if the representations and warranties of the other party prove to be untrue, and allocate risk between the parties, rather than establish matters as facts. The representations and warranties may also be subject to a contractual standard of materiality different from those generally applicable under the securities laws.

Operating Covenants.  The Merger Agreement obligates the Company, from the date of the Merger Agreement until the earlier of the Acceptance Date or termination of the Merger Agreement, subject to certain exceptions, to, and to cause each of its subsidiaries to, use their respective reasonable best efforts to conduct their businesses in all material respects in the ordinary course consistent with past practices and use their respective reasonable best efforts to preserve intact their present business organizations, keep available the services of their officers, employees and consultants and maintain relationships with their customers, suppliers and others having significant business relationships with them. The Merger Agreement also contains specific restrictive covenants as to certain impermissible activities of the Company and its subsidiaries prior to the Acceptance Date, which provide that, subject to certain exceptions, including as contemplated or as permitted by the Merger Agreement, the Company and its subsidiaries will not take certain actions without the prior consent of Holdings, including, among other things: amendments to their organizational documents; splits, combinations or reclassifications of their securities; redemption or repurchase of their securities; dividends and other distributions; issuances or sales of their securities; amendments to the terms of the Company’s securities; capital expenditures; loans, advances or capital contributions; acquisitions or dispositions of material assets or property; sales, assignments, licenses or transfers of certain intellectual property; incurrence of indebtedness other than in the ordinary course; creation of material liens; creation of material limitations or restrictions on the business of the Company; amendment or termination of material contracts; certain increases in compensation or adoption of

26

new benefits plans; settlement of lawsuits; and changes in financial accounting principles or practices or material tax elections.

Access to Information.  Subject to applicable law and certain exceptions, the Merger Agreement provides that until the Effective Time, the Company will provide Holdings, its counsel, financial advisors, auditors and other representatives reasonable access to the properties, offices and books and records of the Company and its subsidiaries and instruct the employees, counsel, financial advisors, auditors and other representatives of the Company and its subsidiaries to cooperate with Holdings in its investigation of the Company and its subsidiaries.

No Solicitation.  In the Merger Agreement, the Company has agreed that neither it nor its subsidiaries will, nor will the Company or any of its subsidiaries authorize or permit any of their respective officers, directors or employees to (and the Company and its subsidiaries will use their respective reasonable best efforts to cause their respective counsel, financial advisors, auditors and other agents and representatives not to), directly or indirectly:

•  solicit, initiate or knowingly take any action to encourage or facilitate the making of an Acquisition Proposal (as defined below);

•  participate in any discussions or negotiations with or furnish any information with respect to the Company or any of its subsidiaries to any third party in connection with an Acquisition Proposal;

•  take any action to render the Rights or Section 203 of the DGCL inapplicable to any transaction contemplated by the term Acquisition Proposal or grant any waiver or release under any standstill or similar agreement with respect to any class of equity securities of the Company or any of its subsidiaries; or

•  approve or enter into any agreement (including an agreement in principle, letter of intent, term sheet or other similar instrument) with respect to an Acquisition Proposal.

Notwithstanding the foregoing, if at any time prior to the Acceptance Date, the Company receives a bona fide written Acquisition Proposal that was not solicited on or after the date of the Merger Agreement, (i) the Company and its representatives may contact the third party or parties making such Acquisition Proposal solely for the purpose of clarifying the terms and conditions thereof and (ii) if the Board determines in good faith (after considering the advice of its outside legal counsel and financial advisors) that such Acquisition Proposal is or could be reasonably expected to result in a Superior Proposal (as defined below), the Company may:

(x) pursuant to a confidentiality agreement with terms no less favorable in the aggregate to the Company than those contained in the confidentiality agreement between Roche and the Company, furnish information (including non-public information) relating to the Company or its subsidiaries to the third party that made an Acquisition Proposal and participate in discussions or negotiations with respect to the Acquisition Proposal, but only if (i) the Company has notified Holdings promptly (but in no event later than 24 hours) after receipt of any Acquisition Proposal or any request for information with respect to the Company or any of its subsidiaries by a third party that has made or is considering making an Acquisition Proposal or any indication that a third party is considering making an Acquisition Proposal (including the identity of the third party and the material terms and conditions of any proposal, request or indication); (ii) the Company shall keep Roche informed, on a prompt basis, of the status of, and any material changes in any such proposal, request or indication; and (iii) the Company promptly provides Holdings any material information furnished to the third party that has not previously been provided to Holdings; and

(y) enter into a definitive agreement with respect to a Superior Proposal, but only if (i) the Company has complied in all material respects with its “no solicitation” obligations described above; (ii) the Company has notified Holdings that the Company Board has determined that the Acquisition Proposal is a Superior Proposal and intends to enter into a definitive agreement with respect to the Superior Proposal and to terminate the Merger Agreement and attached the most current version of such agreement (or a summary containing all the material terms and conditions thereof and identifying the third party that has made the

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Superior Proposal); (iii) Holdings has not made, within three business days after receipt of the written notice, an offer that the Company Board concludes in good faith (after considering the advice of its outside legal and financial advisors) causes such Acquisition Proposal to cease to be a Superior Proposal and (iv) the Company terminates the Merger Agreement and pays the termination fee described below.

The Merger Agreement requires the Company and its subsidiaries to, and to cause their officers, directors and employees (and use their reasonable best efforts to cause their respective counsel, financial advisors, auditors, consultants and other agents and representatives) to cease immediately any and all existing activities, discussions or negotiations, if any, with any person conducted prior to the date of the Merger Agreement with respect to any Acquisition Proposal.

“Acquisition Proposal” means any inquiry, proposal or offer from any person or persons (other than Holdings and its affiliates) relating to any (i) acquisition of assets of the Company and its subsidiaries (including securities of subsidiaries) representing 20% or more of the Company’s consolidated assets or revenues; (ii) acquisition of 20% or more of the outstanding Shares; (iii) tender offer or exchange offer that if consummated would result in any person or entity beneficially owning 20% or more of the outstanding Shares; or (iv) merger, consolidation, share exchange, business combination, recapitalization, reorganization, liquidation, dissolution or similar transaction involving the Company, in each case, other than the transactions contemplated by the Merger Agreement.

“Superior Proposal” means any Acquisition Proposal (with all percentages in the definition of “Acquisition Proposal” changed to 50%) on terms that the Board determines in good faith (after considering the advice of its outside legal and financial advisors and taking into account all the terms and conditions of the Acquisition Proposal) is reasonably likely to be capable of consummation and is more favorable to the Company’s stockholders than the Offer and the Merger (after giving effect to any offer made by Holdings in response to such Acquisition Proposal).

Company Board Recommendation.  The Company has represented to Holdings in the Merger Agreement that the Board, at a meeting duly called and held:

(a) determined that the Merger Agreement and the transactions contemplated in the Merger Agreement are fair to and in the best interests of the Company’s stockholders;

(b) approved the Merger Agreement and the other transactions contemplated in the Merger Agreement, including the Offer and the Merger, and declared the Merger Agreement advisable, in accordance with Delaware Law;

(c) adopted resolutions (subject to the Board’s right to make an Adverse Recommendation Change as described below) recommending that Company stockholders accept the Offer and adopt the Merger Agreement (each of (a), (b) and (c), collectively, the “Company Board Recommendation”).

The Merger Agreement provides that the Board will not fail to make, withdraw or modify in a manner adverse to Holdings the Company Board Recommendation or publicly recommend or announce its intention to enter into an agreement (including an agreement in principle, letter of intent or other similar instrument) with respect to any Acquisition Proposal or otherwise take any action or make any statement inconsistent with the Company Board Recommendation (collectively, an “Adverse Recommendation Change”). Notwithstanding the foregoing, at any time prior to the date the stockholders of the Company approve the Merger Agreement, the Board may make an Adverse Recommendation Change if it determines in good faith (after considering the advice of its outside legal and financial advisors) that the failure to take such action would be inconsistent with its fiduciary duties under Delaware Law.

The Merger Agreement provides that any “stop, look and listen” communication pursuant to Rule 14d-9(f) under the Exchange Act or other factually accurate public statement by the Company that, in each case, merely describes the Company’s receipt of an Acquisition Proposal and the operation of the Merger Agreement with respect thereto and reaffirms the Company Board Recommendation will not be deemed to be an Adverse Recommendation Change. Nothing in the Merger Agreement will prevent the Board from disclosing any information required to be disclosed under applicable law or from complying with Rule 14d-9 or Rule 14e-2(a)

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promulgated under the Exchange Act with respect to an Acquisition Proposal (or any similar communication to holders of Shares in connection with the making or amendment of a tender offer or exchange offer). In addition, nothing in the Merger Agreement will prohibit the Company from taking any action that any court of competent jurisdiction orders the Company to take.

Director and Officer Liability.  The Merger Agreement provides that the Surviving Corporation will (and Holdings will itself as if it were the Surviving Corporation), for six years after the Effective Time, indemnify the current and former officers, directors, employees and employee benefit plan fiduciaries of the Company or any of its subsidiaries in respect of acts, omissions or events occurring at or prior to the Effective Time to the fullest extent provided by the Company’s organizational documents or permitted by applicable law, maintain in effect provisions in the Company’s organizational documents regarding limitations on personal liability of directors and indemnification of, and advancement of expenses to current, and former officers, directors, employees and employee benefit plan fiduciaries and honor the Company’s obligations to these individuals under indemnification agreements to which the Company or a subsidiary of the Company is currently a party. In addition, the Surviving Corporation will (and Holdings will itself as if it were the Surviving Corporation), for six years after the Effective Time, maintain the Company’s current directors’ and officers’ insurance policies and fiduciary liability insurance policies or purchase comparable policies (subject to the limitation that in fulfilling this obligation the Surviving Corporation is not obligated to pay in excess of 300% of the current annual premium paid by the Company for such policies). The Merger Agreement provides that the Surviving Corporation will (and Holdings will itself as if it were the Surviving Corporation) ensure that the successors and assigns of Holdings or the Surviving Corporation, as the case may be, will assume the obligations described above.

Employee Matters.  The Merger Agreement provides that, for a period of one year following the Effective Time, Holdings will provide to all employees of the Company or any of its subsidiaries who continue employment with the Surviving Corporation or any of its affiliates with compensation and benefits that are in the aggregate substantially equivalent to compensation and benefits provided by the Company and its subsidiaries as in effect immediately prior to the Acceptance Date.

Third Party Consents and Regulatory Approvals.  Holdings and the Company have agreed in the Merger Agreement (i) to use their reasonable best efforts to make as promptly as practicable any required filings with any governmental authority or other third party and furnishing all information reasonably required in connection with such filings, (ii) use reasonable best efforts to cause the expiration of any applicable waiting periods, (iii) use reasonable best efforts to obtain any consent, authorization or approval of any private third person required to be obtained by Holdings, Purchaser or the Company or any of their respective subsidiaries in connection with the transactions contemplated by the Merger Agreement; (iv) use reasonable best efforts to prevent the entry of any judgment, injunction, order or decree that would prohibit the consummation of the Offer or the Merger and (v) take any other actions by or with respect to any governmental authority or other third party that are necessary, proper or advisable to consummate the transactions contemplated by the Merger Agreement.

Conditions to the Offer.  Pursuant to the Merger Agreement, Purchaser is not required to accept for payment, or pay for, any Shares tendered in the Offer and may, subject to the Merger Agreement, terminate the Offer if:

(a) prior to the expiration of the Offer, (i) the Minimum Condition has not been satisfied or (ii) there are any restrictions or prohibitions under any applicable antitrust law (including suspensory filings requirements, waiting periods and required actions, consents or clearances by any governmental authority) that would make illegal the consummation of the Offer or the Merger; or

(b) at any time on or after the date of the Merger Agreement and prior to the expiration of the Offer, any of the following conditions exists:

(i) there is a law or judgment, injunction, order or decree of any governmental authority with competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Offer or the Merger;

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(ii) (A) the representations and warranties of the Company contained in the second sentence of Section 4.05 of the Merger Agreement shall not be true and correct in all material respects at and as of immediately prior to the expiration of the Offer as if made at and as of such time (other than such representations and warranties that by their terms address matters only as of another specified time, which shall be true and correct in all material respects only as of such time) or (B) the other representations and warranties of the Company contained in the Merger Agreement (disregarding all materiality and Company Material Adverse Effect (as defined below) qualifications contained therein) shall not be true and correct at and as of immediately prior to the expiration of the Offer as if made at and as of such time (other than representations and warranties that by their terms address matters only as of another specified time, which shall be true and correct only as of such time), except, in the case of clause (B) only, for such matters as have not had and would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect;

(iii) the Company shall have failed to perform in all material respects all of its obligations to be performed or complied with by it under the Merger Agreement prior to such time;

(iv) the Company shall have failed to deliver to Holdings a certificate signed by an executive officer of the Company dated as of the date the Offer expires certifying that the conditions specified in clauses (b)(ii) and (b)(iii) above do not exist; or

(v) the Merger Agreement has been terminated in accordance with its terms.

As used in the Merger Agreement, “Company Material Adverse Effect” means a material adverse effect on (i) the business, operations, results of operations, assets, liabilities or financial condition of the Company and its subsidiaries, taken as a whole, excluding any effect resulting from (A) changes in the financial or securities markets or general economic or political conditions in the United States, (B) changes (including changes of law or regulation) or conditions generally affecting the industry in which the Company and its subsidiaries operate and not specifically relating to or having a materially disproportionate effect on the Company and its subsidiaries, (C) acts of war, sabotage or terrorism or natural disasters involving the United States not having a materially disproportionate effect on the Company and its subsidiaries, (D) the announcement or consummation of the Offer or the transactions contemplated by the Merger Agreement, or (E) any failure by the Company to meet any internal or published budgets, projections, forecasts or predictions of financial performance for any period (it being understood that clause (E) shall not prevent a party from asserting that any fact, change, event, occurrence or effect that may have contributed to such failure independently constitutes or contributes to a Company Material Adverse Effect); or (ii) the Company’s ability to consummate the transactions contemplated by the Merger Agreement.

Subject to the terms and conditions of the Merger Agreement, the foregoing conditions are for the sole benefit of Holdings, the Purchaser and their affiliates. Purchaser expressly reserves the right to waive any of the conditions to the Offer and to make any other changes in the terms of or conditions to the Offer; provided that without the prior consent of the Company (A) the Minimum Condition may not be waived, (B) no change may be made that changes the form of consideration to be paid, decreases the price per Share or the number of Shares sought in the Offer, amends or adds to the conditions to the Offer set forth above or amends any other term of the Offer in any manner adverse to the stockholders of the Company and (C) the expiration date shall not be extended except as otherwise provided in the Merger Agreement. Notwithstanding the foregoing, (x) Purchaser will extend the Offer if at the scheduled or extended expiration date of the Offer any of the conditions of the Offer have not been satisfied or waived, from time to time until such conditions are satisfied or waived and (y) Purchaser will extend the Offer for any period required by any rule, regulation, interpretation or position of the SEC or the NASDAQ Global Select Market applicable to the Offer; provided that in no event will Purchaser be required to extend the Offer beyond the End Date unless Holdings or Purchaser is not then permitted to terminate the Merger Agreement pursuant to the provision described in paragraph (b)(i) under “Termination”, in which case Purchaser will be required to extend the offer beyond the End Date.

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Conditions to the Merger.  The obligations of each party to consummate the Merger are subject to the satisfaction of the following conditions:

•  if required by the DGCL, the Merger Agreement has been adopted by the stockholders of the Company;

•  there is no law or judgment, injunction, order or decree of any governmental authority with competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Merger; and

•  Purchaser has purchased Shares pursuant to the Offer.

Termination.  The Merger Agreement may be terminated and the Offer and/or the Merger may be abandoned at any time prior to the Effective Time (notwithstanding approval of the Merger Agreement by the stockholders of the Company):

(a) by mutual written agreement of the Company and Holdings;

(b) by either the Company or Holdings, if:

(i) the Acceptance Date has not occurred on or before May 31, 2008, subject to extension to June 30, 2008 if, on May 31, 2008, none of the conditions described in “Conditions of the Offer” exists other than as a result of the restrictions under applicable antitrust laws (except that this right to terminate the Merger Agreement will not be available to any party whose breach of any provision of the Merger Agreement results in the failure of the Acceptance Date to occur on or before such time); or

(ii) if there is a law or final non-appealable judgment, injunction, order or decree of any governmental authority with competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Offer or the Merger;

(c) by Holdings, if prior to the Acceptance Date:

(i) an Adverse Recommendation Change has occurred;

(ii) the Company has intentionally and materially breached its non-solicitation obligations under the Merger Agreement (it being understood that actions taken by officers, directors or employees of the Company or its subsidiaries or representatives will not give rise to a right to terminate the Merger Agreement pursuant to this paragraph (c)(ii) so long as neither the Company nor any of its subsidiaries has authorized or permitted any such actions by its officers, directors or employees and the Company and its subsidiaries have used their respective reasonable best efforts to cause such Company representatives not to take any such actions); or

(iii) a breach of any representation or warranty or failure to perform any covenant or agreement on the part of the Company set forth in the Merger Agreement has occurred that would cause the condition set forth in paragraphs (b)(ii) or (b)(iii) of “Conditions of the Offer” to the Merger Agreement to exist, and such breach or failure is incapable of being cured by the End Date;

(d) by the Company, if Holdings, Purchaser or any of their respective affiliates has breached in any material respect any of their respective representations and warranties or failed to perform in any material respect any of their respective covenants or agreements set forth in the Merger Agreement or the guarantee (as described below) which breach or failure to perform is incapable of being cured by the End Date; or

(e) by the Company pursuant to the provision described in paragraph (y) under “No Solicitation” above.

Effect of Termination.  If the Merger Agreement is terminated in accordance with its terms, the Merger Agreement will become void and of no effect with no liability on the part of any party to the other party; provided that, if such termination resulted from the (i) intentional failure of either party to fulfill a condition to the performance of the obligations of the other party or (ii) material breach of either party to perform a

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covenant thereof, such party will be fully liable for any and all liabilities and damages incurred or suffered by the other party as a result of such failure or breach.

Termination Fee.  The Company has agreed in the Merger Agreement to pay Holdings a fee in immediately available funds (in the case of a termination of the Merger Agreement by Holdings, within two business days after such termination and, in the case of a termination by the Company, immediately before and as a condition to such termination) equal to $110,000,000 if:

(i) the Merger Agreement is terminated by Holdings pursuant to the provision described in paragraph (c)(i) under “Termination” above or by the Company pursuant to the provision described in paragraph (e) under “Termination” above; or

(ii) the Merger Agreement is terminated by Holdings or the Company pursuant to the provision described in paragraph (b)(i) under “Termination” above, if after the date of the Merger Agreement and prior to the date of termination, an Acquisition Proposal has been publicly announced or otherwise been communicated to the Board or the Company’s stockholders and not withdrawn and within nine months following the date of such termination, the Company has entered into a definitive agreement with respect to or recommended to its stockholders an Acquisition Proposal or an Acquisition Proposal has been consummated (provided that for purposes of the provision described in this paragraph each reference to “20%” in the definition of Acquisition Proposal will be deemed to be a reference to “50%”).

General Expenses.  Except as otherwise provided in the Merger Agreement, all costs and expenses incurred in connection with the Merger Agreement will be paid by the party incurring such cost or expense.

In connection with the execution of the Merger Agreement, Roche and the Company entered into a guarantee pursuant to which Roche has guaranteed the performance and discharge of Holdings’ payment and performance obligations under the Merger Agreement. In addition, Thomas D. Brown, Rodney F. Dammeyer, Edward M. Giles, Christopher M. Gleeson, Thomas M. Grogan, M.D., Hany Massarany, Lawerence L. Mehren, Mark C. Miller, Mark D. Tucker and James R. Weersing entered into a tender and support agreement with Holdings pursuant to which, among other things, those stockholders and agreed to tender their shares in the offer.

(b) The Rights Agreement.

On January 21, 2008, the Company entered into the Rights Amendment. The effect of the Rights Amendment is to permit the performance of the transactions contemplated by the Merger Agreement and prevent Holdings or any of its affiliates or associates from becoming an “Acquiring Person” (as defined in the Rights Agreement) and a “Distribution Date” (as defined in the Rights Agreement) from occurring. The Rights Amendment also provides for the termination of the Rights Agreement immediately prior to the Effective Time. This description of the Rights Amendment is qualified in its entirety by reference to the full text of the Rights Amendment, a copy of which is filed as Exhibit (a)(32) to this Amendment and is incorporated herein by reference.

(c) The Stockholder Tender and Support Agreement.

In connection with the execution of the Merger Agreement, all of the Company’s directors and executive officers (other than John Patience and Jack Schuler) entered into a Stockholder Tender and Support Agreement, dated as of January 21, 2008 (the “Support Agreement”), with Holdings. Under the Support Agreement, such directors and executive officers agreed, among other things, to tender all Shares beneficially owned by them pursuant to the Offer, to vote such Shares in favor of the adoption of the Merger Agreement at any meeting of Company stockholders and to grant to Holdings an irrevocable proxy to vote such Shares in favor of the Merger Agreement. This description of the Support Agreement is qualified in its entirety by reference to the full text of the Support Agreement, a copy of which is filed as Exhibit (a)(33) to this Amendment and is incorporated herein by reference.

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(d) The Guarantee.

In connection with the execution of the Merger Agreement, the Company and Roche entered into a Guarantee, dated as of January 21, 2008 (the “Guarantee”). Under the Guarantee, Roche unconditionally and irrevocably guarantees the full and punctual performance and discharge of Holding’s payment and performance obligations under the Merger Agreement. This description of the Guarantee is qualified in its entirety by reference to the full text of the Guarantee, a copy of which is filed as Exhibit (a)(34) to this Amendment and is incorporated herein by reference.

Item 8.   Additional Information.

Item 8 is hereby amended by replacing the last sentence of subsection (a) thereof with the following:

Item 8 is hereby further amended by adding the following at the end of subsection (d) thereof:

The Board has approved the Merger Agreement and the transactions contemplated thereby, including the Revised Offer and the Merger, and has declared that the provisions of Section 203 of the DGCL do not apply to the transactions contemplated by the Merger Agreement.

Item 8 is hereby further amended by replacing subsection (c) thereof with the following:

(c) Arizona Corporate Takeovers Act.

On June 29, 2007, Roche filed a complaint in the U.S. District Court for the District of Arizona against the Company and the Attorney General of the State of Arizona alleging that Sections 10-2721 through 10-2727 and Sections 10-2741 through 10-2743 of the Arizona Revised Statutes are unconstitutional insofar as they seek to regulate tender offers for corporations incorporated under the laws of states other than Arizona. Roche moved for a preliminary injunction that would prevent the application of the Arizona statutory provisions to the Offer, and on August 22, 2007, the court granted that preliminary injunction. Roche and the Company later stipulated to the entry of a permanent injunction, after which the court entered a consent judgment barring the Company from taking any action to invoke, apply or enforce the above provisions of the Arizona Revised Statutes with respect to the Offer.

Item 8 is hereby further amended by adding the following at the end of subsection (d) thereof:

On August 22, 2007, the State-Boston Retirement System, an alleged stockholder of the Company, filed a putative class action lawsuit in the Court of Chancery for the State of Delaware against the Company and its directors on behalf of a proposed class of Company stockholders other than the Director Defendants and their affiliates. The complaint alleges that the Director Defendants breached their fiduciary duties to Company stockholders in connection with the Offer. The action seeks, among other things, injunctive relief requiring the Director Defendants to negotiate with Roche and/or to seek out and evaluate other value-maximizing alternatives and an award of damages, plaintiff’s attorneys’ fees, expert fees and interest. On October 26, 2007, plaintiff amended its complaint, which defendants later moved to dismiss for failure to state a claim. That motion has not yet been briefed.

On August 24, 2007, Geneva Blazek, an alleged stockholder of the Company, filed a putative class action lawsuit in the Superior Court of the State of Arizona in and for the County of Pima on behalf of a proposed class of Company stockholders other than the Director Defendants and their affiliates. The complaint alleges that the Director Defendants breached their fiduciary duties to Company stockholders in connection with the Offer. The action seeks, among other things, injunctive relief barring the Director Defendants from employing any unreasonable defensive mechanisms, an order directing the Director Defendants to seek out and evaluate other value-maximizing alternatives, and an award of damages and plaintiff’s attorneys’ fees. On October 5, 2007, defendants filed a motion to stay the action in light of the similar Roche Holdings v. Gleeson and State-Boston Retirement System cases pending before the Delaware Chancery Court, or, in the alternative, to dismiss the complaint for failure to state a claim. That motion has been fully briefed and argued, but no decision has been rendered.

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Pursuant to the Merger Agreement, Holdings, Purchaser and the Company have agreed (1) to promptly following the date of the Merger Agreement, enter into and file stipulations staying all litigation pending between them or their respective affiliates and representatives, or commenced by or on behalf of any of them in connection with the Offer, and (2) to promptly following the Acceptance Date, enter into and file stipulations dismissing with prejudice all such litigation and releasing all claims against the other parties to the Merger Agreement (and their affiliates and representatives) based on any action or omission that occurred prior to the date of such stipulations.

Forward-Looking Statements

This Schedule 14D-9 contains forward-looking statements that may state the Company’s, its management’s or the Board’s intentions, beliefs, expectations or predictions for the future. Forward-looking statements include, without limitation, any statement that may predict, forecast, indicate or imply future results, performance or achievements, and may contain words such as “believe,” “anticipate,” “expect,” “estimate,” “project,” “intend,” “will be,” “will continue,” “will likely result” or words or phrases of similar meaning. These forward-looking statements are subject to numerous risks and uncertainties, and actual results may vary materially. The Company may not achieve anticipated future operating results and product development activities may not be as successful as the Company expects in terms of the timing of product availability to the market or customer rates of adoption. Other risks and uncertainties include risks associated with the development, manufacturing, marketing and sale of products, competitive factors, general economic conditions, legal disputes, government actions and those other risks and uncertainties described in the Company’s most recent Annual Report on Form 10-K filed with the SEC, and subsequent reports filed by the Company with the SEC from time to time. Copies of the Company’s filings made with the SEC are available through the SEC’s electronic data gathering analysis retrieval system (EDGAR) at www.sec.gov. The Company undertakes no obligation following the date of this Amendment to update or revise its forward-looking statements or to update the reasons actual results could differ materially from those anticipated in forward-looking statements. Undue reliance should not be placed upon any such forward-looking statements, which speak only as of the date such statements are made. Past performance is not indicative of future results. The Company cannot guarantee any future operating results, activity, performance or achievement.

Item 9.   Exhibits.

Item 9 is hereby amended so as to add the following new exhibits:

Exhibit No.		Document
	(a)(29)	Letter to Company stockholders communicating the recommendation of the Company’s board of directors*
	(a)(30)	Opinion of Goldman, Sachs & Co., dated January 21, 2008*
	(a)(31)	Opinion of Merrill Lynch, Pierce, Fenner & Smith Incorporated, dated January 21, 2008*
	(a)(32)	First Amendment to Rights Agreement, dated as of January 21, 2008, between the Company and Wells Fargo Bank, N.A.
	(a)(33)	Stockholder Tender and Support Agreement, dated as of January 21, 2008, among Roche Holdings, Inc., Thomas D. Brown, Rodney Dammeyer, Edward M. Giles, Christopher M. Gleeson, Thomas M. Grogan, Hany Massarany, Lawrence L. Mehren, Mark C. Miller, Mark D. Tucker and James R. Weersing
	(a)(34)	Guarantee, dated as of January 21, 2008, between the Company and Roche Holding Ltd
	(e)(16)	Agreement and Plan of Merger, dated as of January 21, 2008, among the Company, Roche Holdings, Inc. and Rocket Acquisition Corporation

* Included in material mailed to Company stockholders

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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 statement is true, complete and correct.

VENTANA MEDICAL SYSTEMS, INC.

Christopher M. Gleeson

President and Chief Executive Officer

Date: January 25, 2008

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INDEX OF EXHIBITS

Exhibit No.		Document
	(a)(1)	Letter to the Company’s stockholders dated July 11, 2007*(1)
	(a)(2)	Press release issued by the Company on July 11, 2007(1)
	(a)(3)	Letter to the Company’s employees dated July 11, 2007(1)
	(a)(4)	Employee/customer/supplier “Frequently Asked Questions”(1)
	(a)(5)	Press release issued by the Company on July 19, 2007(1)
	(a)(6)	Investor presentation materials for Earnings Conference Call held on July 20, 2007(1)
	(a)(7)	Transcript of Earnings Conference Call held on July 20, 2007(1)
	(a)(8)	Press release issued by the Company on July 26, 2007(1)
	(a)(9)	Letter to the Company’s employees dated July 26, 2007(1)
	(a)(10)	Press release issued by the Company on August 21, 2007(1)
	(a)(11)	Letter to the Company’s employees dated August 21, 2007(1)
	(a)(12)	Letter to the Company’s employees dated August 22, 2007(1)
	(a)(13)	Complaint filed by the State-Boston Retirement System, individually and on behalf of all those similarly situated, on August 22, 2007, in the Court of Chancery for the State of Delaware, New Castle County(1)
	(a)(14)	Complaint filed by Geneva Blazek, individually and on behalf of all those similarly situated, on August 24, 2007, in the Superior Court of the State of Arizona in and for the County of Pima(1)
	(a)(15)	Press release issued by the Company on September 19, 2007(1)
	(a)(16)	Letter to the Company’s employees dated September 21, 2007(1)
	(a)(17)	Press release issued by the Company on October 18, 2007(1)
	(a)(18)	Transcript of Earnings Conference Call held on October 18, 2007(1)
	(a)(19)	Press release issued by the Company on October 29, 2007(1)
	(a)(20)	Press release issued by the Company on November 13, 2007(1)
	(a)(21)	Letter to the Company’s employees dated November 13, 2007(1)
	(a)(22)	Press release issued by the Company on December 5, 2007(1)
	(a)(23)	Letter to the Company’s employees dated December 5, 2007(1)
	(a)(24)	Press release issued by the Company on January 16, 2008(1)
	(a)(25)	Press release issued by the Company on January 22, 2008(1)
	(a)(26)	Letter to the Company’s employees dated January 22, 2008(1)
	(a)(27)	Employee Frequently Asked Questions dated January 22, 2008(1)
	(a)(28)	Email to the Company’s employees dated January 22, 2008(1)
	(a)(29)	Letter to Company stockholders communicating the recommendation of the Company’s board of directors*
	(a)(30)	Opinion of Goldman, Sachs & Co., dated January 21, 2008*
	(a)(31)	Opinion of Merrill Lynch, Pierce, Fenner & Smith Incorporated, dated January 21, 2008*
	(a)(32)	First Amendment to Rights Agreement, dated as of January 21, 2008, between the Company and Wells Fargo Bank, N.A.
	(a)(33)	Stockholder Tender and Support Agreement, dated as of January 21, 2008, among Roche Holdings, Inc., Thomas D. Brown, Rodney Dammeyer, Edward M. Giles, Christopher M. Gleeson, Thomas M. Grogan, Hany Massarany, Lawrence L. Mehren, Mark C. Miller, Mark D. Tucker and James R. Weersing
	(a)(34)	Guarantee, dated as of January 21, 2008, between the Company and Roche Holding Ltd
	(e)(1)	Excerpts from the Company’s Definitive Proxy Statement on Schedule 14A relating to the 2007 Annual Meeting of Stockholders as filed with the SEC on March 28, 2007(1)
	(e)(2)	1988 Stock Option Plan and forms of agreements thereunder (Incorporated by reference to Exhibit 10.7(A) to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)

Exhibit No.		Document
	(e)(3)	1996 Stock Option Plan and forms of agreements thereunder (Incorporated by reference to Exhibit 10.7(B) to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)
	(e)(4)	1996 Employee Stock Purchase Plan (Incorporated by reference to Exhibit 10.8(B) to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)
	(e)(5)	1996 Directors Option Plan (Incorporated by reference to Exhibit 10.8(C) to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)
	(e)(6)	1998 Nonstatutory Stock Option Plan and forms of agreements thereunder (Incorporated by reference to Exhibit 4.1 to the Company’s Registration Statement on Form S-8 (SEC File No. 333-92883), filed with the SEC on December 16, 1999 and Exhibit 4.1 to the Company’s Registration Statement on Form S-8 (SEC File No. 333-105976), filed with the SEC on June 10, 2003)
	(e)(7)	2001 Outside Director Stock Option Plan (Incorporated by reference to Exhibit 4.1 to the Company’s Registration Statement on Form S-8 (SEC File No. 333-69658), filed with the SEC on September 19, 2001)
	(e)(8)	2005 Equity Incentive Plan (Incorporated by reference to the Company’s Definitive Proxy Statement on Schedule 14A (SEC File No. 000-20931) filed with the SEC on March 31, 2005)
	(e)(9)	2005 Employee Stock Purchase Plan (Incorporated by reference to the Company’s Definitive Proxy Statement on Schedule 14A (SEC File No. 000-20931) filed with the SEC on March 31, 2005)
	(e)(10)	2005 Equity Incentive Plan Agreement (Incorporated by reference to Exhibit 10.8.1 to the Company’s Annual Report on Form 10-K (SEC File No. 000-20931) filed with the SEC on February 16, 2007)
	(e)(11)	2005 Equity Incentive Plan Agreement (Accelerated Vesting) (Incorporated by reference to Exhibit 10.8.2 to the Company’s Annual Report on Form 10-K (SEC File No. 000-20931) filed with the SEC on February 16, 2007)
	(e)(12)	Preferred Share Rights Agreement, dated as of May 6, 1998 between the Company and Norwest Bank Minnesota, N.A., including the Certificate of Designations, the form of Rights Certificate and the Summary of Rights attached thereto as Exhibits A, B and C, respectively (Incorporated by reference to Exhibit 1 to the Company’s Registration Statement on Form 8-A12G filed with the SEC on June 9, 1998)
	(e)(13)	Restated Certificate of Incorporation of the Company (Incorporated by reference to Exhibit 3.1(i)(a) to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)
	(e)(14)	Certificate of Amendment to Certificate of Incorporation (Incorporated by reference to Exhibit 3.3 to the Company’s Quarterly Report on Form 10-Q (SEC File No. 000-20931), filed with the SEC on July 26, 2005)
	(e)(15)	Form of Indemnification Agreement for directors and officers (Incorporated by reference to Exhibit 10.6 to the Company’s Registration Statement on Form S-l (SEC File No. 333-4461), declared effective by the SEC July 26, 1996)
	(e)(16)	Agreement and Plan of Merger, dated as of January 21, 2008, among the Company, Roche Holdings, Inc. and Rocket Acquisition Corporation

*	Included in materials mailed to the Company’s stockholders.
(1)	Previously filed with Schedule 14D-9 or an amendment thereto.

EX-99.(A)(29)

Exhibit (a)(29)

Ventana Medical Systems, Inc.
1910 Innovation Park Drive
Tuscon, Arizona 85755

Phone: (520) 887-2155
Toll Free: (800) 227-2155
www.ventanamed.com

January 25, 2008

Dear Fellow Stockholder:

I wanted to let you know that your Board of Directors has recommended that stockholders accept Roche’s revised offer to purchase all of the outstanding shares of Ventana common stock for $89.50 per share.

After an evaluation of strategic alternatives and thoughtful consideration, as well as consultation with outside financial and legal advisors, your Board believes that the transaction with Roche at $89.50 per share is fair and in the best interests of our stockholders, and we strongly recommend that you tender your shares of Ventana common stock into this revised offer.

In making this recommendation, the Board considered a number of factors, including:

•  The revised offer represents a premium of 5% to Ventana’s closing price on January 18, 2008 (the last trading day prior to the announcement of Roche’s revised offer), a 19% premium to Roche’s initial offer of $75 per share of Ventana common stock announced on June 27, 2007, and a 72% premium to the closing price of shares of Ventana common stock on June 25, 2007 (the last trading day prior to the announcement of Roche’s initial offer).

•  The Board believes that the revised offer reflects much of the long-term value creation potential of Ventana’s business plan, value-creation initiatives and marketplace opportunities, without subjecting Ventana stockholders to any execution risk or risks associated with the industry in which Ventana operates.

•  The Board believes that there are no more desirable strategic or other transactional alternatives available at this time.

•  The Board believes that, particularly in light of the absence of competing offers since Roche announced its initial offer, it is unlikely that Roche would be willing to pay a higher price for Ventana than $89.50 per share.

A complete discussion of these and other factors your Board of Directors took into account in making its recommendation is included in the enclosed amendment to Schedule 14D-9. We urge you to read the Schedule 14D-9 carefully and in its entirety so that you will be fully informed as to your Board of Directors’ recommendation.

We greatly appreciate your continued support and encouragement.

Sincerely,

Christopher M. Gleeson

President and Chief Executive Officer

If you have any questions concerning the Schedule 14D-9 or need additional copies of Ventana’s publicly filed materials, please contact Innisfee M&A Incorporated at 212-750-5833.

EX-99.(A)(30)

Exhibit (a)(30)

PERSONAL AND CONFIDENTIAL

January 21, 2008

Board of Directors
Ventana Medical Systems, Inc.
1910 Innovation Park Drive
Tucson, AZ 85755

Gentlemen:

You have requested our opinion as to the fairness from a financial point of view to the holders of the outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Ventana Medical Systems, Inc. (the “Company”) of the $89.50 per Share in cash proposed to be received by holders of Shares in the Tender Offer and the Merger (each as defined below), pursuant to the Agreement and Plan of Merger, dated as of January 21, 2008 (the “Agreement”), by and among Roche Holdings, Inc. (“Roche”), Rocket Acquisition Corporation, an indirect wholly owned subsidiary of Roche (“Acquisition Sub”), and the Company. The Agreement provides for a tender offer for all of the Shares (the “Tender Offer”) pursuant to which Acquisition Sub will pay $89.50 per Share in cash for each Share accepted. The Agreement further provides that, following completion of the Tender Offer, Acquisition Sub will be merged with and into the Company (the “Merger”) and each outstanding Share will be converted into the right to receive $89.50 in cash.

Goldman, Sachs & Co. and its affiliates are engaged in investment banking and financial advisory services, securities trading, investment management, principal investment, financial planning, benefits counseling, risk management, hedging, financing, brokerage activities and other financial and non-financial activities and services for various persons and entities. In the ordinary course of these activities and services, Goldman, Sachs & Co. and its affiliates may at any time make or hold long or short positions and investments, as well as actively trade or effect transactions, in the equity, debt and other securities (or related derivative securities) and financial instruments (including bank loans and other obligations) of the Company, Roche and any of their respective affiliates or any currency or commodity that may be involved in the transaction contemplated by the Agreement (the “Transaction”) for their own account and for the accounts of their customers. We have acted as financial advisor to the Board of Directors of the Company in connection with, and have participated in certain of the negotiations leading to, the Transaction. We expect to receive fees for our services in connection with the Transaction, the principal portion of which is contingent upon consummation of the Transaction, and the Company has agreed to reimburse our expenses and indemnify us against certain liabilities arising out of our engagement. In addition, we have provided certain investment banking and other financial services to Roche and its affiliates from time to time, including having acted as financial advisor to Genentech, a majority owned subsidiary of Roche, with respect to its issuance of Senior Notes (aggregate principal amount of $2,000,000,000) in June 2005. We also may provide investment banking and other financial services to the Company, Roche and their respective affiliates in the future. In connection with the above-described services we have received, and may receive, compensation.

In connection with this opinion, we have reviewed, among other things, the Tender Offer Statement on Schedule TO, as amended, originally filed on June 27, 2007 by Roche Holding Ltd and Acquisition Sub; Schedule 14D-9 originally filed on July 11, 2007 by the Company; annual reports to stockholders and Annual Reports on Form 10-K of the Company for the five fiscal years ended December 31, 2006; certain interim reports to stockholders and Quarterly Reports on Form 10-Q of the Company; certain other communications from the Company to its stockholders; certain publicly available research analyst reports for the Company; and certain internal financial analyses and forecasts for the Company prepared by its management (the “Forecasts”). We also have held discussions with members of the senior management of the Company regarding their assessment of the past and current business operations, financial condition and future prospects of the

Board of Directors
Ventana Medical Systems, Inc.
January 21, 2008
Page Two

Company, including their views of the risks and uncertainties of achieving the Forecasts. In addition, we have reviewed the reported price and trading activity for the Shares, compared certain financial and stock market information for the Company with similar information for certain other companies the securities of which are publicly traded, reviewed the financial terms of certain recent business combinations in the healthcare diagnostics industry specifically and in other industries generally and performed such other studies and analyses, and considered such other factors, as we considered appropriate.

For purposes of rendering this opinion, we have relied upon and assumed, without assuming any responsibility for independent verification, the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by us. In addition, we have not made an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or off-balance-sheet assets and liabilities) of the Company or any of its subsidiaries and we have not been furnished with any such evaluation or appraisal. Our opinion does not address any legal, regulatory, tax or accounting matters.

Our opinion does not address the underlying business decision of the Company to engage in the Transaction, or the relative merits of the Transaction as compared to any strategic alternatives that may be available to the Company. This opinion addresses only the fairness from a financial point of view, as of the date hereof, of the $89.50 per Share in cash to be received by the holders in the Tender Offer and Merger pursuant to the Agreement. We do not express any view on, and our opinion does not address, any other term or aspect of the Agreement or Transaction, including, without limitation, the fairness of the Transaction to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of the Company or Roche; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of the Company or Roche, or class of such persons in connection with the Transaction, whether relative to the $89.50 per Share in cash to be received by the holders in the Tender Offer and the Merger pursuant to the Agreement or otherwise. Our opinion is necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to us as of, the date hereof and we assume no responsibility for updating, revising or reaffirming this opinion based on circumstances, developments or events occurring after the date hereof. Our advisory services and the opinion expressed herein are provided for the information and assistance of the Board of Directors of the Company in connection with its consideration of the Transaction and such opinion does not constitute a recommendation as to whether or not any holder of Shares should tender such Shares in connection with the Tender Offer or how any holder of Shares should vote with respect to the Merger or any other matter. This opinion has been approved by a fairness committee of Goldman, Sachs & Co.

Based upon and subject to the foregoing, it is our opinion that, as of the date hereof, the $89.50 in cash to be received by the holders of Shares in the Tender Offer and the Merger is fair from a financial point of view to such holders.

Very truly yours,

(GOLDMAN, SACHS & CO.)

EX-99.(A)(31)

Exhibit (a)(31)

January 21, 2008

Board of Directors

Ventana Medical Systems, Inc.

1910 Innovation Park Drive

Tucson, Arizona 85755

Members of the Board of Directors:

Ventana Medical Systems, Inc. (the “Company”), Roche Holdings, Inc. (the “Acquiror”) and Rocket Acquisition Corporation, a newly formed, wholly owned subsidiary of the Acquiror (the “Acquisition Sub”), are entering into an Agreement and Plan of Merger, dated as of January 21, 2008 (the “Agreement”), pursuant to which (i) the Acquiror and the Acquisition Sub would amend the tender offer (the “Tender Offer”) for all outstanding shares of the common stock, par value $0.001 per share, of the Company (the “Company Shares”) to increase the purchase price to $89.50 per share, net to the seller in cash (the “Consideration”), and (ii) Acquisition Sub would be merged with the Company in a merger (the “Merger”), in which each Company Share not acquired in the Tender Offer, other than Company Shares held in treasury or held by the Acquiror or its subsidiaries, or as to which dissenter’s rights have been perfected, would be converted into the right to receive the Consideration. The Tender Offer and the Merger, taken together, are referred to as the “Transaction”.

You have asked us whether, in our opinion, the Consideration to be received by the holders of the Company Shares pursuant to the Transaction is fair from a financial point of view to such holders, other than the Acquiror, the Acquisition Sub and their respective affiliates.

In arriving at the opinion set forth below, we have, among other things:

(1)	Reviewed certain publicly available business and financial information relating to the Company that we deemed to be relevant;
(2)	Reviewed certain information, including financial forecasts, relating to the business, earnings, cash flow, assets, liabilities and prospects of the Company furnished to us by the Company;
(3)	Conducted discussions with members of senior management of the Company concerning the matters described in clauses 1 and 2 above;
(4)	Reviewed the market prices and valuation multiples for the Company Shares and compared them with those of certain other publicly traded companies that we deemed to be relevant;
(5)	Reviewed the results of operations of the Company and compared them with those of certain other publicly traded companies that we deemed to be relevant;
(6)	Compared the proposed financial terms of the Transaction with the financial terms of certain other transactions that we deemed to be relevant;

Board of Directors
Ventana Medical Systems, Inc.
January 21, 2008
Page 2

(7)	Participated in certain discussions and negotiations among representatives of the Company and the Acquiror and their financial and legal advisors;
(8)	Reviewed the Agreement; and
(9)	Reviewed such other financial studies and analyses and took into account such other matters as we deemed necessary, including our assessment of general economic, market and monetary conditions.

In preparing our opinion, we have assumed and relied on the accuracy and completeness of all information supplied or otherwise made available to us, discussed with or reviewed by or for us, or publicly available, and we have not assumed any responsibility for independently verifying such information or undertaken an independent evaluation or appraisal of any of the assets or liabilities of the Company or been furnished with any such evaluation or appraisal, nor have we evaluated the solvency or fair value of the Company under any state or federal laws relating to bankruptcy, insolvency or similar matters. In addition, we have not assumed any obligation to conduct any physical inspection of the properties or facilities of the Company. With respect to the financial forecast information furnished to or discussed with us by the Company, we have assumed that they have been reasonably prepared and reflect the best currently available estimates and judgment of the Company’s management as to the expected future financial performance of the Company.

Our opinion is necessarily based upon market, economic and other conditions as they exist and can be evaluated on, and on the information made available to us as of, the date hereof.

We are acting as financial advisor to the Company in connection with the Transaction and will receive a fee from the Company for our services, a significant portion of which is contingent upon the consummation of the Transaction. In addition, the Company has agreed to indemnify us for certain liabilities arising out of our engagement.

We have, in the past, provided financial advisory and financing services to the Acquiror and its affiliates unrelated to the Transaction and have received fees for the rendering of such services. In addition, in the ordinary course of our business, we or our affiliates may actively trade the Company Shares and other securities of the Company, as well as securities of the Acquiror, for our own account and for the accounts of customers and, accordingly, may at any time hold a long or short position in such securities.

This opinion is for the use and benefit of the Board of Directors of the Company. Our opinion does not address the merits of the underlying decision by the Company to engage in the Transaction and does not constitute a recommendation to any shareholder as to whether such shareholder should tender any Company Shares pursuant to the Tender Offer and how such shareholder should vote on the proposed Merger or any matter related thereto. In addition, you have not asked us to address, and this opinion does not address, the fairness to, or any other consideration of, the holders of any class of securities, creditors or other constituencies of the Company, other than the holders of the Company Shares. In rendering this opinion, we express no view or opinion with respect to the fairness (financial or otherwise) of the amount or nature or any other aspect of any compensation payable to or to be received by any officers, directors, or employees of any parties to the Transaction, or any class of such persons, relative to the Consideration. Our opinion has been authorized for issuance by the U.S. Fairness Opinion (and Valuation Letter) Committee of Merrill Lynch.

Board of Directors
Ventana Medical Systems, Inc.
January 21, 2008
Page 3

On the basis of and subject to the foregoing, we are of the opinion that, as of the date hereof, the Consideration to be received by the holders of the Company Shares pursuant to the Transaction is fair from a financial point of view to the holders of such shares, other than the Acquiror, the Acquisition Sub and their respective affiliates.

Very truly yours,

MERRILL LYNCH, PIERCE, FENNER & SMITH

INCORPORATED

EX-99.(A)(32)

Exhibit (a)(32)

FIRST AMENDMENT TO RIGHTS AGREEMENT

     AMENDMENT, dated as of January 21, 2008 (this “Amendment”), to that certain Rights Agreement, dated as of May 6, 1998 (the “Rights Agreement”), between Ventana Medical Systems, Inc., a Delaware corporation (the “Company”), and Wells Fargo Bank, N.A. (as successor to Norwest Bank Minnesota, N.A.), as rights agent (the “Rights Agent”).

     WHEREAS, the Company, Roche Holdings, Inc., a Delaware corporation (“Purchaser”), and Rocket Acquisition Corp., a Delaware corporation and an indirect wholly-owned subsidiary of Purchaser (“Merger Subsidiary”), have proposed to enter into an Agreement and Plan of Merger (the “Merger Agreement”) pursuant to which, among other things, (1) Merger Subsidiary will amend its tender offer (the “Offer”) providing for the purchase of all of the issued and outstanding shares of common stock of the Company, par value $0.001 per share (“Company Common Stock”), together with the associated preferred stock purchase rights issued pursuant to the Rights Agreement (“Company Rights”) for so long as such Company Rights are outstanding, for cash, and (2) upon consummation of the Offer, Merger Subsidiary will merge with and into the Company (the “Merger”), in each case, upon the terms and subject to the conditions set forth in the Merger Agreement;

     WHEREAS, the board of directors of the Company has voted to amend the Rights Agreement so that (1) the execution of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Offer and the Merger, do not, and will not, result in the ability of any person to exercise any Company Rights or enable or require such Company Rights to separate from the shares of Company Common Stock to which they are attached or to be triggered or become exercisable and (2) the Rights Agreement will expire immediately prior to the effective time of the Merger; and

     WHEREAS, pursuant to Section 27(a) of the Rights Agreement, an appropriate officer of the Company has delivered to the Rights Agent a certificate stating that this Amendment is in compliance with the terms of Section 27 of the Rights Agreement and, pursuant to Section 27(a) of the Rights Agreement, the Company has directed the Rights Agent to execute this Amendment;

     NOW, THEREFORE, in consideration of the premises and the mutual agreements set forth herein, the parties hereto hereby agree as follows:

     1. Definitions; Interpretation. All capitalized terms used herein, unless otherwise defined herein, shall have the meanings given them in the Rights Agreement, and each reference in the Rights Agreement to “this Agreement,” “hereof,” “herein,” “hereunder” or “hereby” and each other similar reference shall be deemed to refer to the Rights Agreement as amended hereby.

2. Amendments to Section 1.

(a) The definition of “Acquiring Person” in Section 1(a) of the Rights Agreement is hereby amended by adding the following to the end of such definition:

Notwithstanding anything in this Agreement that might otherwise be deemed to the contrary, neither Purchaser, Merger Subsidiary, nor any of either of their respective Affiliates or Associates shall be deemed to be an Acquiring Person solely by reason or as a result of (i) the approval, execution or delivery of the Merger Agreement, including any amendment or supplement thereto, (ii) the public announcement of such execution and delivery, (iii) the public announcement or the amendment of the Offer or (iv) the consummation of any of the transactions specifically contemplated by the Merger Agreement (including the Offer and the Merger), each upon the terms and subject to the conditions set forth in the Merger Agreement.

(b) The definition of “Distribution Date” in Section 1(l) of the Rights Agreement is hereby amended by adding the following to the end of such definition:

Notwithstanding anything in this Agreement that might otherwise be deemed to the contrary, no Distribution Date shall be deemed to have occurred solely by reason or as a result of (i) the approval, execution or delivery of the Merger Agreement, including any amendment or supplement thereto, (ii) the public announcement of such execution and delivery, (iii) the public announcement or the amendment of the Offer or (iv) the consummation of any of the transactions specifically contemplated by the Merger Agreement (including the Offer and the Merger), each upon the terms and subject to the conditions set forth in the Merger Agreement.

(c) The definition of “Expiration Date” in Section 1(q) of the Rights Agreement is hereby amended and restated in its entirety as follows:

“Expiration Date” shall mean the earliest to occur of: (i) the Close of Business on the Final Expiration Date, (ii) the Redemption Date, (iii) the time at which the Board of Directors orders the exchange of the Rights as provided in Section 24 hereof or (iv) the time immediately prior to the Effective Time (as defined in the Merger Agreement).

(d) Section 1 of the Rights Agreement is hereby amended by adding the following paragraphs after Section 1(s) but before Section 1(t):

2

(s-1) “Merger” shall mean the merger of Merger Subsidiary with and into the Company upon the terms and subject to the conditions set forth in the Merger Agreement.

(s-2) “Merger Agreement” shall mean that certain Agreement and Plan of Merger, dated as of January 21, 2008, among the Company, Purchaser and Merger Subsidiary.

(e) Section 1 of the Rights Agreement is hereby amended by adding the following paragraph after Section 1(t) but before Section 1(u):

(t-1) “Offer” shall have the meaning ascribed to such term in the Merger Agreement.

(f) Section 1 of the Rights Agreement is hereby amended by adding the following paragraph after Section 1(ee) but before Section 1(ff):

(ee-1) “Purchaser” shall mean Roche Holdings, Inc., a Delaware corporation.

(ee-2) “Merger Subsidiary” shall mean Rocket Acquisition Corp., a Delaware corporation and an indirect wholly-owned subsidiary of Purchaser.

(g) The definition of “Triggering Event” in Section 1(qq) of the Rights Agreement is hereby amended by deleting the period at the end of such definition and adding the following to the end of such definition:

; provided that, if such Person is determined not have become an Acquiring Person pursuant to Section 1(a) hereof, then no Triggering Event shall be deemed to have occurred.

     2. Amendment to Section 13. Section 13 of the Rights Agreement is hereby amended by adding the following paragraph immediately following Section 13(f):

(g) Notwithstanding anything in this Agreement that might otherwise be deemed to the contrary, the provisions of this Section 13 shall not be applicable to the Merger or the Offer.

     3. Amendment to Exhibit B. Exhibit B to the Rights Agreement is hereby amended by substituting the following in place of the first sentence of the first paragraph thereof:

NOT EXERCISABLE AFTER THE EARLIEST OF (i) MARCH 9, 2008, (ii) THE DATE TERMINATED BY THE COMPANY, (iii) THE DATE THE COMPANY EXCHANGES THE RIGHTS PURSUANT TO THE RIGHTS AGREEMENT OR (iv) THE

3

TIME IMMEDIATELY PRIOR TO THE EFFECTIVE TIME (AS DEFINED IN THE MERGER AGREEMENT).

     4. Amendments to Exhibit C.

(a) Exhibit C to the Rights Agreement is hereby amended by substituting the following in place of the paragraph captioned “Expiration of Rights:”

The Rights expire on the earliest of (a) March 9, 2008, (b) exchange or redemption of the Rights as described above or (c) the time immediately prior to the Effective Time (as defined in that certain Agreement and Plan of Merger, dated as of January 21, 2008 (the “Merger Agreement”), among the Company, Roche Holdings, Inc. (“Purchaser”) and Rocket Acquisition Corp. (“Merger Subsidiary”)).

(b) Exhibit C to the Rights Agreement is hereby amended by adding the following immediately following the paragraph captioned “Taxes:”

Merger Agreement: Neither Purchaser, Merger Subsidiary, nor any of either of their respective affiliates or associates will be deemed to be an Acquiring Person, and no Distribution Date will be deemed to have occurred, solely by reason or as a result of (a) the approval, execution or delivery of the Merger Agreement, (b) the public announcement of such execution and delivery, (c) the public announcement or the amendment of the Offer (as defined in the Merger Agreement) or (d) the consummation of any of the transactions specifically contemplated by the Merger Agreement.

     5. Descriptive Headings. The descriptive headings of this Amendment have been inserted for convenience only and shall not control or affect the meaning or construction of any of the provisions of this Amendment.

     6. Governing Law. This Amendment shall be deemed to be a contract made under the laws of the State of Delaware and for all purposes shall be governed by and construed in accordance with the laws of such state applicable to contracts made and performed entirely within such state.

4

     7. Counterparts. This Amendment may be executed in any number of counterparts; each of such counterparts shall for all purposes be deemed to be an original; and all such counterparts shall together constitute but one and the same instrument.

     8. Other Terms Unchanged. Except as expressly set forth herein, this Amendment shall not, by implication or otherwise, alter, modify, amend or in any way affect any of the terms, conditions, obligations, covenants or agreements contained in the Rights Agreement, all of which are ratified and affirmed in all respects and shall continue in full force and effect.

     9. Severability. If any provision of this Amendment is held by a court of competent jurisdiction to be invalid, void or unenforceable, the remainder of the provisions of this Amendment shall remain in full force and effect and shall in no way be affected, impaired or invalidated.

     10. Effective Date. This Amendment shall become effective as of the date first above written.

* * * * * *

5

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed as of the day and year first above written.

VENTANA MEDICAL SYSTEMS, INC.
 

/s/ Christopher M. Gleeson  

Christopher M. Gleeson 

President and Chief Executive Officer 

WELLS FARGO BANK, N.A.,
as Rights Agent

/s/ Cindy Gesme

Cindy Gesme

Assistant Vice President

Amendment to Rights Agreement

EX-99.(A)(33)

Exhibit (a)(33)

STOCKHOLDER TENDER AND SUPPORT AGREEMENT

     This Stockholder Tender and Support Agreement dated as of January 21, 2008 (this “Agreement”) is among each of the individuals or entities listed on a signature page hereto (each, a “Stockholder”) and Roche Holdings, Inc., a Delaware corporation (“Parent”). Capitalized terms used but not defined herein have the meanings assigned to them in the Agreement and Plan of Merger dated as of the date of this Agreement (the “Merger Agreement”) among Parent, Rocket Acquisition Corporation, a Delaware corporation and a wholly-owned indirect subsidiary of Parent (“Merger Subsidiary”), and Ventana Medical Systems, Inc., a Delaware corporation (the “Company”).

     WHEREAS, each Stockholder beneficially owns (as defined in Rule 13d-3 under the Securities Exchange Act of 1934, as amended) shares of common stock of the Company, par value $0.001 per share (“Company Common Stock”);

     WHEREAS, concurrently with the execution and delivery of this Agreement, Parent, Merger Subsidiary and the Company are entering into the Merger Agreement, which provides for, among other things, the making of a tender offer by Merger Subsidiary for all of the outstanding shares of the Company Common Stock and the merger of Merger Subsidiary with and into the Company, upon the terms and subject to the conditions set forth therein; and

     WHEREAS, as a condition to Parent’s willingness to enter into the Merger Agreement, Parent has required that each Stockholder enter into this Agreement.

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants, representations, warranties and agreements set forth herein, and intending to be legally bound, the parties hereby agree as follows:

     SECTION 1. Agreement to Tender. Each Stockholder hereby agrees to validly tender or cause to be tendered in the Offer any and all shares of Company Common Stock currently beneficially owned by such Stockholder (excluding for purposes of this Section 1 any shares of Company Common Stock that are the subject of unexercised Company Stock Options and any Company Restricted Shares and Company Performance Units) and any additional shares of Company Common Stock with respect to which such Stockholder becomes the beneficial owner (including, without limitation, whether by purchase, by the exercise of Company Stock Options or otherwise) after the date of this Agreement (collectively, but excluding any shares that are disposed of in compliance with Section 6(b), the “Subject Shares”) pursuant to and in accordance with the terms of the Offer no later than two Business Days after the receipt by such Stockholder of all documents or instruments required to be delivered pursuant to the terms of the Offer, including but not limited to the letter of transmittal in the case of certificated Subject Shares. In furtherance of the foregoing, at the time of such

tender, each Stockholder shall (i) deliver to the depositary designated in the Offer (the “Depositary”) (A) a letter of transmittal with respect to its Subject Shares complying with the terms of the Offer, (B) a certificate or certificates representing such Subject Shares or an “agent’s message” (or such other evidence, if any, of transfer as the Depositary may reasonably request) in the case of a book-entry transfer of any Subject Shares and (C) all other documents or instruments, to the extent applicable, required to be delivered by other stockholders of the Company pursuant to the terms of the Offer, and/or (ii) instruct its broker or such other Person that is the holder of record of any Subject Shares to tender such Subject Shares pursuant to and in accordance with the terms of the Offer. Each Stockholder agrees that once its Subject Shares are tendered, such Stockholder will not withdraw or cause to be withdrawn any of such Subject Shares from the Offer, unless and until this Agreement shall have been terminated in accordance with Section 11(d).

     SECTION 2. Documentation and Information. Each Stockholder (i) consents to and authorizes the publication and disclosure by Parent of such Stockholder’s identity and holding of Subject Shares, the nature of such Stockholder’s commitments, arrangements and understandings under this Agreement (including, for the avoidance of doubt, the disclosure of this Agreement) and any other information, in each case, that Parent reasonably determines is required to be disclosed by applicable Law in any press release, the Offer Documents, the Company Proxy Statement (including all schedules and documents filed with the SEC), or any other disclosure document in connection with the Offer, the Merger and any transactions contemplated by the Merger Agreement and (ii) agrees promptly to give to Parent any information it may reasonably require for the preparation of any such disclosure documents. Each Stockholder agrees to promptly notify Parent of any required corrections with respect to any information supplied by such Stockholder specifically for use in any such disclosure document, if and to the extent that any such information shall have become false or misleading in any material respect.

     SECTION 3. Voting Agreement. Each Stockholder agrees that if such Stockholder’s Subject Shares have not been previously accepted for payment pursuant to the Offer, such Stockholder hereby agrees that at any meeting (whether annual or special and whether or not an adjourned or postponed meeting) of the holders of Company Common Stock, however called (each, a “Company Stockholders Meeting”), or in connection with any written consent of the holders of Company Common Stock, such Stockholder shall vote (or cause to be voted) or deliver a written consent (or cause a written consent to be delivered) with respect to all such Stockholder’s Subject Shares, in each case, to the fullest extent that such Subject Shares are entitled to be voted at the time of any vote or action by written consent:

     (a) in favor of (i) the adoption of the Merger Agreement and (ii) without limitation of the preceding clause (i), the approval of any proposal to adjourn or

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postpone the Company Stockholders Meeting to a later date if there are not sufficient votes for adoption of the Merger Agreement on the date on which the Company Stockholders Meeting is held; and

     (b) against any action or agreement that would reasonably be expected to frustrate the purposes of, impede, hinder, interfere with, prevent, delay or adversely affect the consummation of the transactions contemplated by the Merger Agreement, including, but not limited to, any agreement or arrangement related to an Acquisition Proposal.

     SECTION 4. Irrevocable Proxy. Each Stockholder hereby irrevocably appoints Parent as attorney-in-fact and proxy for and on behalf of such Stockholder, for and in the name, place and stead of such Stockholder, to:

     (a) attend any and all Company Stockholder Meetings;

     (b) vote, express consent or dissent or issue instructions to the record holder to vote such Stockholder’s Subject Shares in accordance with the provisions of Section 3 at any such meeting; and

     (c) grant or withhold, or issue instructions to the record holder to grant or withhold, in accordance with the provisions of Section 3, all written consents with respect to the Subject Shares. The foregoing proxy shall be deemed to be a proxy coupled with an interest, is irrevocable (and as such shall survive and not be affected by the death, incapacity, mental illness or insanity of such Stockholder) until the end of the Agreement Period (as defined below) and shall not be terminated by operation of Law or upon the occurrence of any other event other than the termination of this Agreement pursuant to Section 11(d). Each Stockholder authorizes such attorney and proxy to substitute any other Person to act hereunder, to revoke any substitution and to file this proxy and any substitution or revocation with the Secretary of the Company. Each Stockholder hereby affirms that the irrevocable proxy set forth in this Section 4 is given in connection with and granted in consideration of and as an inducement to Parent entering into the Merger Agreement and that such irrevocable proxy is given to secure the obligations of the Stockholder under Section 3 hereof. Parent covenants and agrees with each Stockholder that Parent will exercise the foregoing proxy consistent with the provisions of Section 3 hereof.

     SECTION 5. Representations and Warranties of Each Stockholder. Each Stockholder, severally but not jointly as to any other Stockholder, represents and warrants to Parent as follows (it being understood that, except where expressly stated to be given or made as of the date hereof only, the representations and warranties contained in this Agreement shall be made as of the date hereof, as of the Acceptance Date and, if such Stockholder’s Subject Shares have not been previously accepted for payment pursuant to the Offer, as of the date of each Company Stockholders Meeting:

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     (a) Organization. If such Stockholder is not an individual, it is duly organized and validly existing and in good standing under the laws of the jurisdiction of its organization.

     (b) Authorization. If such Stockholder is not an individual, it has full corporate, limited liability company, partnership or trust power and authority to execute and deliver this Agreement and to perform its obligations hereunder. If such Stockholder is an individual, he has full legal capacity, right and authority to execute and deliver this Agreement and to perform his obligations hereunder. If such Stockholder is not an individual, the execution, delivery and performance by such Stockholder of this Agreement and the consummation by such Stockholder of the transactions contemplated hereby have been duly authorized by all necessary action on the part of such Stockholder. This Agreement has been duly executed and delivered by such Stockholder and constitutes a valid and legally binding obligation of such Stockholder.

     (c) No Violation.

     (i) The execution and delivery of this Agreement by such Stockholder does not, and the performance by such Stockholder of such Stockholder’s obligations hereunder will not, (A) if such Stockholder is not an individual, contravene, conflict with, or result in any violation or breach of any provision of its articles of incorporation, bylaws or similar organizational documents, (B) assuming compliance with the matters referred to in Section 5(c)(ii), contravene, conflict with, or result in a violation or breach of any provision of applicable Law or any judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction or (C) constitute a default, or an event that, with or without notice or lapse of time or both, could become a default, under, or cause or permit the termination, cancellation, acceleration or other change of any right or obligation or the loss of any benefit to which the such Stockholder is entitled under any provision of any agreement or other instrument binding upon such Stockholder, except, in the case of clauses (B) and (C), for such matters as would not reasonably be expected to have, individually or in the aggregate, a material adverse effect on such Stockholder’s ability to perform its obligations under this Agreement.

     (ii) No consent, approval, order, authorization or permit of, or registration, declaration or filing with or notification to, any Governmental Authority or any other Person is required by or with respect to such Stockholder in connection with the execution and delivery of this Agreement by such Stockholder or the performance by such Stockholder of such Stockholder’s obligations hereunder, except for the filing with the SEC of any Schedules 13D or 13G or amendments to Schedules 13D or 13G and filings under Section 16 of the 1934 Act as may be required in connection with this Agreement and the transactions contemplated hereby

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and except for any actions or filings the absence of which would not reasonably be expected to have, individually or in the aggregate, a material adverse effect on such Stockholder’s ability to perform its obligations under this Agreement.

     (d) Ownership of Subject Shares. As of the date hereof, such Stockholder is, and (except with respect to any Subject Shares Transferred in accordance with Section 6(b) hereof or accepted for payment pursuant to the Offer) at all times during the Agreement Period will be, the beneficial owner of such Stockholder’s Subject Shares with no restrictions on such Stockholder’s rights of disposition pertaining thereto, except for any applicable restrictions on Transfer under the 1933 Act. Except to the extent of any Subject Shares acquired after the date hereof (which shall become Subject Shares upon that acquisition), the number of shares of the Company Common Stock set forth on Schedule A opposite the name of such Stockholder are the only shares of Company Common Stock beneficially owned by such Stockholder on the date of this Agreement. Other than the Subject Shares and any shares of Company Common Stock that are the subject of unexercised Company Stock Options and any Company Restricted Shares and Company Performance Units held by such Stockholder (the number of which is set forth opposite the name of such Stockholder on Schedule A), such Stockholder does not own any shares of Company Stock or any options to purchase or rights to subscribe for or otherwise acquire any securities of the Company and has not interest in or voting rights with respect to any securities of the Company.

     (e) Proxy. None of such Stockholder’s Subject Shares are subject to any voting agreement or proxy on the date of this Agreement, except pursuant to this Agreement.

     (f) Absence of Litigation. With respect to such Stockholder, as of the date hereof, there is no action, suit, investigation or proceeding pending against, or, to the knowledge of such Stockholder, threatened against or otherwise affecting, such Stockholder or any of its or his properties or assets (including such Stockholder’s Subject Shares) that could reasonably be expected to impair the ability of such Stockholder to perform his or its obligations hereunder or to consummate the transactions contemplated hereby on a timely basis.

     (g) Opportunity to Review; Reliance. Such Stockholder understands and acknowledges that Parent is entering into the Merger Agreement in reliance upon such Stockholder’s execution, delivery and performance of this Agreement.

     (h) Finders’ Fees. No investment banker, broker, finder or other intermediary is entitled to a fee or commission from Parent or the Company in respect of this Agreement based upon any arrangement or agreement made by or on behalf of such Stockholder in his capacity as such.

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     (i) No Other Representations or Warranties. Except for the representations and warranties expressly contained in this Section 5, such Stockholder makes no express or implied representation or warranty with respect to any Stockholder, the Subject Shares or otherwise.

     SECTION 6. No Proxies for or Encumbrances on Subject Shares.

     (a) Except pursuant to the terms of this Agreement, during the Agreement Period, no Stockholder shall (nor permit any Person under such Stockholder’s control to), without the prior written consent of Parent, directly or indirectly, (i) grant any proxies, powers of attorney, rights of first offer or refusal or enter into any voting trust, (ii) sell (including short sell), assign, transfer, tender, pledge, encumber, grant a participation interest in, hypothecate or otherwise dispose of (including by gift) (each, a “Transfer”), (iii) otherwise permit any Liens to be created on, or (iv) enter into any contract, agreement, option, instrument or other arrangement or understanding with respect to the direct or indirect Transfer of, any Subject Shares. No Stockholder shall, and shall not permit any Person under such Stockholder’s control or any of its or their respective representatives to, seek or solicit any such Transfer or any such contract, agreement, option, instrument or other arrangement or understanding.

     (b) Notwithstanding the foregoing, each Stockholder shall have the right to Transfer all or any portion of its or his Subject Shares to a Permitted Transferee of such Stockholder if and only if such Permitted Transferee shall have agreed in writing, in a manner reasonably acceptable in form and substance to Parent, (i) to accept such Subject Shares subject to the terms and conditions of this Agreement and (ii) to be bound by this Agreement and to agree and acknowledge that such Person shall constitute a Stockholder for all purposes of this Agreement. “Permitted Transferee” means, with respect to any Stockholder, (A) any other Stockholder, (B) a spouse, lineal descendant or antecedent, brother or sister, adopted child or grandchild or the spouse of any child, adopted child, grandchild or adopted grandchild of such Stockholder, (C) any trust, the trustees of which include only the Persons named in clauses (A) or (B) and the beneficiaries of which include only the Persons named in clauses (A) or (B), (D) any corporation, limited liability company or partnership, the stockholders, members or general or limited partners of which include only the Persons named in clauses (A) or (B), or (E) if such Stockholder is a trust, the beneficiary or beneficiaries authorized or entitled to receive distributions from such trust.

     (c) Each Stockholder hereby authorizes Parent to direct the Company to impose stop orders to prevent the Transfer of any Subject Shares on the books of the Company in violation of this Agreement.

     SECTION 7. Waiver of Appraisal Rights. Each Stockholder hereby irrevocably waives any and all rights he or it may have as to appraisal, dissent or any similar or related matter with respect to any of such Stockholder’s Subject

6

Shares that may arise with respect to the Merger or any of the transactions contemplated by the Merger Agreement, including, without limitation, under Section 262 of Delaware Law.

     SECTION 8. Notices of Certain Events. Each Stockholder shall notify Parent of any development occurring after the date hereof that causes, or that would reasonably be expected to cause, any breach of any of the representations and warranties of such Stockholder set forth in Section 5.

     SECTION 9. Further Assurances. Parent and each Stockholder will each execute and deliver, or cause to be executed and delivered, all further documents and instruments and use their respective 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 under applicable Laws and regulations, to perform their respective obligations under this Agreement.

     SECTION 10. Certain Adjustments. In the event of a stock split, stock dividend or distribution, or any change in the Company Common Stock by reason of a stock split, reverse stock split, recapitalization, combination, reclassification, readjustment, exchange of shares or the like, the term “Subject Shares” shall be deemed to refer to and include such shares as well as all such stock dividends and distributions and any securities into which or for which any or all of such shares may be changed or exchanged.

     SECTION 11. Miscellaneous.

     (a) Notices. All notices, requests and other communications to any party hereunder shall be in writing (including facsimile transmission) and shall be given,

     If to Parent:

Roche Holdings, Inc.
1220 N. Market St., Suite #334
Wilmington, DE 19801-2535
Attention: Carol Fiederlein
Facsimile No.: (302) 425-4713

     with a copy to:

Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
Attention:  Christopher Mayer
                   Marc O. Williams
Facsimile No.: (212) 450-3800

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     If to a Stockholder, to his, her or its address set forth on a signature page hereto, with copies to:

Sidley Austin LLP
1 South Dearborn Street
Chicago, Illinois 60603
Attention:  Thomas A. Cole
                   Frederick C. Lowinger
                   Michael A. Gordon
                   Robert L. Verigan
Facsimile No.: (312) 853-7036

Snell & Wilmer LLP
One Arizona Center
400 East Van Buren
Phoenix, Arizona 85004
Attention: Daniel M. Mahoney
Facsimile No.: (602) 382-6070

and/or to such other address or facsimile number as such party may hereafter specify for the purpose by notice to the other parties hereto. All such notices, requests and other communications shall be deemed received on the date of receipt by the recipient thereof if received prior to 5 p.m. on a business day in the place of receipt. Otherwise, any such notice, request or communication shall be deemed to have been received on the next succeeding business day in the place of receipt.

     (b) Amendment and Waivers.

     (i) Any provision of this Agreement may be amended or waived during the Agreement Period if, but only if, such amendment or waiver is in writing and is signed, in the case of an amendment, by each party to this Agreement or, in the case of a waiver, by each party against whom the waiver is to be effective.

     (ii) No failure or delay by any party in exercising any right, power or privilege hereunder shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right, power or privilege. The rights and remedies herein provided shall be cumulative and not exclusive of any rights or remedies provided by Law.

     (c) Binding Effect; Benefit; Assignment.

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     (i) The provisions of this Agreement shall be binding upon and shall inure to the benefit of the parties hereto and their respective successors and assigns. No provision of this Agreement is intended to confer any rights, benefits, remedies, obligations or liabilities hereunder upon any Person other than the parties hereto and their respective successors and assigns.

     (ii) Neither any Stockholder, on the one hand, nor Parent, on the other hand, may assign this Agreement or any of his or its rights, interests or obligations hereunder (whether by operation of Law or otherwise) without the prior written approval of Parent or such Stockholder, as applicable, except that Parent may transfer or assign its rights and obligations under this Agreement, in whole or from time to time in part, to one or more of its Affiliates at any time; provided that such transfer or assignment shall not relieve Parent of its obligations under this Agreement.

     (d) Termination. This Agreement shall automatically terminate and become void and of no further force or effect on the earlier of (i) the Effective Time, (ii) the termination of this Agreement by written notice from Parent to the Stockholders, (iii) the occurrence of an Adverse Recommendation Change, and (iv) the termination, or modification in a manner adverse to the stockholders of the Company, of the Offer or the termination of the Merger Agreement in accordance with its terms (the period from the date hereof through such time being referred to as the “Agreement Period”); provided that (A) Sections 11(a), 11(b), 11(e), 11(h) and 11(n) shall survive such termination and (B) no such termination shall relieve or release any Stockholder or Parent from any obligations or liabilities arising out of his or its breach of this Agreement prior to its termination.

     (e) Governing Law; Consent to Jurisdiction; Waiver of Jury Trial.

     (i) This Agreement shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law rules of such state.

     (ii) The parties hereto agree that any suit, action or proceeding seeking to enforce any provision of, or based on any matter arising out of or in connection with, this Agreement or the transactions contemplated hereby shall be brought in the Delaware Chancery Court or, if such court shall not have jurisdiction, in any federal court located in the State of Delaware or other Delaware state court, and each of the parties hereby irrevocably consents to the jurisdiction of such courts (and of the appropriate appellate courts therefrom) in any such suit, action or proceeding and irrevocably waives, to the fullest extent permitted by law, any objection that it may now or hereafter have to the laying of the venue

9

of any such suit, action or proceeding in any such court or that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum. Process in any such suit, action or proceeding may be served on any party anywhere in the world, whether within or without the jurisdiction of any such court. Without limiting the foregoing, each party agrees that service of process on such party as provided in Section 11(a) shall be deemed effective service of process on such party.

     (iii) EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

     (f) Severability. If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction or other Governmental Authority to be invalid, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions of this Agreement shall remain in full force and effect and shall in no way be affected, impaired or invalidated so long as the economic or legal substance of the transactions contemplated hereby is not affected in any manner materially adverse to any party. Upon such a determination, the parties shall negotiate in good faith to modify this Agreement so as to effect the original intent of the parties as closely as possible in an acceptable manner in order that the transactions contemplated hereby be consummated as originally contemplated to the fullest extent possible.

     (g) Specific Performance. The parties hereto agree that irreparable damage would occur if any provision of this Agreement were not performed in accordance with the terms hereof and that the parties shall be entitled to an injunction or injunctions to prevent breaches of this Agreement or to enforce specifically the performance of the terms and provisions hereof, in addition to any other remedy to which they are entitled at law or in equity.

     (h) Expenses. All costs and expenses incurred in connection with this Agreement shall be paid by or on behalf of the party incurring such cost or expense.

     (i) Counterparts; Effectiveness. This Agreement may be signed in any number of counterparts, each of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument. This Agreement shall become effective when each party hereto shall have received a counterpart hereof signed by all of the other parties hereto. Until and unless each party has received a counterpart hereof signed by the other party hereto, this Agreement shall have no effect and no party shall have any right or obligation hereunder (whether by virtue of any other oral or written agreement or other communication).

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     (j) Entire Agreement. This Agreement constitutes the entire agreement between the parties with respect to the subject matter of hereof and thereof and supersede all prior agreements and understandings, both oral and written, between the parties with respect to the subject matter hereof and thereof.

     (k) Headings. The Section headings contained in this Agreement are inserted for convenience only and shall not affect in any way the meaning or interpretation of this Agreement.

     (l) Interpretation. Any reference to any national, state, local or foreign Law shall be deemed also to refer to all rules and regulations promulgated thereunder, unless the context otherwise requires. When a reference is made in this Agreement to Sections or Schedules, such reference shall be to a Section of or Schedule to this Agreement unless otherwise indicated. Whenever the words “include,” “includes” or “including” are used in this Agreement, they shall be deemed to be followed by the words “without limitation.” In this Agreement, the Stockholder of any Company Common Stock held in trust shall be deemed to be the relevant trust and/or the trustees thereof acting in their capacities as such trustees, in each case as the context may require to be most protective of Parent, including for purposes of such trustees’ representations and warranties as to the proper organization of the trust, their power and authority as trustees and the non-contravention of the trust’s governing instruments.

     (m) No Presumption. This Agreement shall be construed without regard to any presumption or rule requiring construction or interpretation against the party drafting or causing any instrument to be drafted.

     (n) Obligations. The obligations of each Stockholder under this Agreement are several and not joint, and no Stockholder shall have any liability or obligation under this Agreement for any breach hereunder by any other Stockholder.

     (o) Stockholder Capacity. Each Stockholder is signing and entering this Agreement solely in his capacity as the beneficial owner of Subject Shares, and nothing herein shall limit or affect in any way any actions that may be hereafter taken by him in his capacity as an employee, officer or director of the Company or any Subsidiary of the Company.

     (p) Non-Survival of Representations and Warranties. None of the representations and warranties in this Agreement or in any instrument delivered pursuant to this Agreement shall survive the Effective Time.

     SECTION 12. Representations and Warranties of Parent. Parent represents and warrants to each Stockholder, as of the date hereof and as of the date of each Company Stockholders Meeting and the Acceptance Date, that it has full power and authority to execute and deliver this Agreement and to perform its

11

obligations hereunder. The execution, delivery and performance by Parent of this Agreement and the consummation by Parent of the transactions contemplated hereby have been duly authorized by all necessary action on the part of Parent. This Agreement constitutes a valid and legally binding obligation of Parent.

[The next page is the signature page]

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     The parties hereto have executed this Tender and Support Agreement as of the date first written above.

ROCHE HOLDINGS, INC.
By:	/s/ Carol Fiederlein
	Name: Carol Fiederlein
	Title: Vice President and
	Corporate Secretary

[Stockholder Signatures Begin on the Next Page]

Edward M. Giles
 

/s/ Edward M. Giles  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Christopher M. Gleeson
 

/s/ Christopher M. Gleeson  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Hany Massarany
 

/s/ Hany Massarany  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

James R. Weersing
 

/s/ James R. Weersing  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Thomas D. Brown
 

/s/ Thomas D. Brown  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Thomas M. Grogan, M.D.
 

/s/ Thomas M. Grogan, M.D.  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Rodney F. Dammeyer
 

/s/ Rodney F. Dammeyer  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Mark D. Tucker
 

/s/ Mark D. Tucker  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Mark C. Miller
 

/s/ Mark C. Miller  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

Lawrence L. Mehren
 

/s/ Lawrence L. Mehren  

Address: 

[Stockholder Tender and Support Agreement — Stockholder Signature Page]

SCHEDULE A

			Number of
			Shares
			Subject
			to
	Number of		Unexercised		Number of		Number of
	Shares		Company		Company		Company
	Beneficially		Stock		Restricted		Performance
Name	Owned		Options		Shares		Units
Thomas D. Brown		0		48,114		0		0
Rodney Dammeyer		0		37,453		0		0
Edward M. Giles		231,082		115,724		0		0
Christopher M. Gleeson		75,857		590,263		0		4,354
Thomas M. Grogan, M.D.		63,771		212,097		0		0
Hany Massarany		12,632		226,164		0		15,000
Lawrence L. Mehren		0		66,666		0		0
Mark C. Miller		40,800		128,954		0		0
Mark D. Tucker		11,823		36,000		11,000		0
James R. Weersing		118,568		81,209		0		0

A-1

EX-99.(A)(34)

Exhibit (a)(34)

GUARANTEE

     GUARANTEE dated as of January 21, 2008 by Roche Holding Ltd, a joint stock company organized under the laws of Switzerland (the “Guarantor”), for the benefit of Ventana Medical Systems, Inc. (the “Beneficiary”).

W I T N E S S E T H :

     WHEREAS, Roche Holdings, Inc., a Delaware corporation (the “Obligor”) is an indirect wholly-owned subsidiary of Guarantor; and

     WHEREAS, the Obligor has entered into an Agreement and Plan of Merger (the “Merger Agreement”) dated as of January 21, 2008 among Beneficiary, Obligor and Rocket Acquisition Corporation (the “Merger Subsidiary”);

     NOW, THEREFORE, in consideration of the promises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Guarantor agrees as follows:

     1. The Guarantee, etc. The Guarantor hereby unconditionally and irrevocably guarantees the full and punctual performance and discharge of Obligor’s payment and performance obligations, including the obligation to cause the Merger Subsidiary to perform its obligations, under the Merger Agreement (each a “Guaranteed Obligation”). The Guaranteed Obligations include, without limitation, an unconditional guarantee of payment and not of collectability.

     2. Guarantee Unconditional. The obligations of the Guarantor hereunder shall be unconditional and absolute and, without limiting the generality of the foregoing, shall not be released, discharged or otherwise affected by:

     (a) any extension, renewal, settlement, compromise, waiver or release in respect of any obligation of the Obligor under the Merger Agreement, by operation of law or otherwise;

     (b) any modification or amendment of or supplement to the Merger Agreement;

     (c) the existence of any claim, set-off or other rights which the Guarantor may have at any time against the Obligor;

     (d) any change in the corporate existence, structure or ownership of the Obligor, or any insolvency, bankruptcy, reorganization

or other similar proceeding affecting the Obligor or its assets or any resulting release or discharge of any obligation of the Obligor contained in the Merger Agreement; or

     (e) any other act or omission to act or delay of any kind by the Obligor, the Beneficiary or any other person or any other circumstance whatsoever which might, but for the provisions of this paragraph, constitute a legal or equitable discharge of or defense to the Guarantor’s obligations hereunder.

     3. Discharge Only Upon Satisfaction in Full. The Guarantor’s obligations hereunder shall remain in full force and effect until all Guaranteed Obligations shall have been performed in full. In the event that any payment to the Beneficiary in respect of any Guaranteed Obligation is rescinded or must otherwise be returned for any reason whatsoever, the Guarantor shall remain liable hereunder with respect to such Guaranteed Obligation as if such payment had not been made. The Guarantor hereby unconditionally and irrevocably agrees not to exercise any rights that it may now have or hereafter acquire against Obligor or any other Person primarily or secondarily liable with respect to any of the Guaranteed Obligations that arise from the existence, payment, performance or enforcement of the Guarantor’s obligations hereunder including, without limitation, any right of subrogation, reimbursement, exoneration, contribution or indemnification and any right to participate in any claim or remedy of the Beneficiary against any other Person primarily or secondarily liable with respect to any of the Guaranteed Obligations, whether such claim, remedy or right arises in equity or under contract, statute or common law, including, without limitation, the right to take or receive from Obligor or any other Person primarily or secondarily liable with respect to any of the Guaranteed Obligations, directly or indirectly, in cash or other property or by set-off or in any other manner, payment or security on account of such claim, remedy or right, in each case unless and until all of the Guaranteed Obligations and all other amounts payable under this Guarantee shall have been paid in full in cash. If any amount shall be paid to the Guarantor in violation of the immediately preceding sentence, such amount shall be received and held in trust for the benefit of the Beneficiary, and shall forthwith be paid or delivered to the Beneficiary in the same form as so received (with any necessary endorsement or assignment) to be credited and applied to the amounts payable under this Guarantee.

     4. Waivers by the Guarantor. The Guarantor irrevocably waives all defenses, including, without limitation, suretyship defenses, and any requirement that at any time any action be taken by any person or entity against the Obligor, the Guarantor or any other person or entity.

     5. Representations and Warranties. The Guarantor represents and warrants to the Beneficiary that:

     (a) the Guarantor is duly organized and validly existing under the laws of the jurisdiction of its organization;

     (b) the execution, delivery and performance by the Guarantor of this Guarantee are within the Guarantor’s corporate powers and have been duly authorized by all necessary corporate action;

     (c) this Guarantee has been duly executed and delivered by the Guarantor and constitutes a legal, valid and binding obligation of the Guarantor, enforceable in accordance with its terms, subject to applicable bankruptcy, insolvency, reorganization, moratorium, and other laws affecting creditors’ rights generally and subject to general principles of equity, regardless of whether considered in a proceeding in equity or at law;

     (d) the execution, delivery and performance of this Guarantee (i) do not require any consent or approval of, registration or filing with, or other action by, any governmental authority, except such as have been obtained and are in full force and effect, (ii) will not violate any applicable law or regulation or the charter, by-laws or other organizational documents of the Guarantor or any order of any court or governmental authority, and (iii) will not violate or result in a default under any indenture, agreement or other instrument binding upon the Guarantor or any of its properties or give rise to a right thereunder to require the Guarantor to make any payment;

     (e) there are no actions, suits or proceedings by or before any arbitrator or court or other governmental authority pending against or, to the knowledge of the Guarantor, threatened against or affecting the Guarantor as to which there is a reasonable possibility of adverse determinations that, in the aggregate, could reasonably be expected to result in a material adverse effect on the assets, operations or condition, financial or otherwise, of the Guarantor or the ability of the Guarantor to perform its obligations under this Guarantee; and

     (f) the audited consolidated balance sheet of the Obligor as of December 31, 2006 and the related statements of income, cash flows, recognized income and expense and changes in equity for the fiscal year then ended, together with the notes thereto, fairly present in all material respects the consolidated financial position, results of operations and cash flows of the Obligor as of December 31, 2006 and for the year then ended.

     6. Notices. All notices, requests and other communications to any party hereunder shall be in writing (including, without limitation, facsimile transmission) and shall be given, as follows:

     (i) if to the Guarantor, to it at:

Roche Holding Ltd
Grenzacherstrasse 124
CH-4070 Basel
Switzerland
Attention: General Counsel
Facsimile No.: +41 61 688 3196

     with a copy to:

Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
Attention: Christopher Mayer
                  Marc O. Williams
Facsimile No.: (212) 450-3800

     (ii) if to the Obligor, to it at:

Roche Holdings, Inc.
1220 N. Market St., Suite #334
Wilmington, DE 19801-2535
Attention: Carol Fiederlein, Secretary
Facsimile No.: (302) 425 4713

     with a copy to:

Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
Attention: Christopher Mayer
                  Marc O. Williams
Facsimile No.: (212) 450-3800

     (iii) if to the Beneficiary, to it at:

Ventana Medical Systems, Inc.
1910 E. Innovation Park Drive
Tucson, Arizona 85755
Attention: Chief Executive Officer
                    General Counsel
Facsimile No.: (520) 229-4204

     with a copy to:

Sidley Austin LLP
One South Dearborn Street
Chicago, Illinois 60603
Attention: Thomas A. Cole
                    Frederick C. Lowinger
                    Michael A. Gordon
                    Robert L. Verigan
Facsimile No.: (312) 853-7036

     and with a copy to:

Snell & Wilmer LLP
One Arizona Center
400 East Van Buren
Phoenix, Arizona 85004
Attention: Daniel M. Mahoney
Facsimile No.: (602) 382-6070

or to such other address or facsimile number as such party may hereafter specify for the purpose by notice to the other parties hereto. All such notices, requests and other communications shall be deemed received on the date of receipt by the recipient thereof if received prior to 5 p.m. on a business day in the place of receipt. Otherwise, any such notice, request or communication shall be deemed to have been received on the next succeeding business day in the place of receipt.

     7. Defined Terms. Capitalized terms used but not defined herein shall have the meanings assigned to them in the Merger Agreement.

     8. No Waiver. No failure or delay by the Beneficiary in exercising any right, power or privilege under this Guarantee or the Merger Agreement shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right, power or privilege.

     9. Amendments and Waivers. Any provision of this Guarantee may be amended or waived if, but only if, such amendment or waiver is in writing and is signed by the Beneficiary and the Guarantor.

     10. Successors and Assigns. This Guarantee shall be binding upon the Guarantor and its successors and permitted assigns, for the benefit of the Beneficiary and its successors and assigns. The Guarantor may not assign its rights, duties or obligations hereunder to any other Person (except by operation of law) without the prior written consent of the Beneficiary.

     11. Governing Law. This Guarantee shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law rules of such state.

     12. Jurisdiction. The parties hereto agree that any suit, action or proceeding seeking to enforce any provision of, or based on any matter arising out of or in connection with, this Guarantee or the transactions contemplated hereby shall be brought in the Court of Chancery of the State of Delaware in and for New Castle County, Delaware or, if such court shall not have jurisdiction, in any federal court located in the State of Delaware or other Delaware state court, and each of the parties hereby irrevocably consents to the jurisdiction of such courts (and of the appropriate appellate courts therefrom) in any such suit, action or proceeding and irrevocably waives, to the fullest extent permitted by law, any objection that it may now or hereafter have to the laying of the venue of any such suit, action or proceeding in any such court or that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum. Process in any such suit, action or proceeding against any party other than a party having its registered office in Switzerland may be served anywhere in the world, whether within or without the jurisdiction of any such court. Process in any such suit, action or proceeding against any party having its registered office in Switzerland shall be made in accordance with the provisions of the Hague Convention of 15 November 1965 on the Service Abroad of Judicial and Extrajudicial Documents in Civil or Commercial Matters. Without limiting the foregoing, each party agrees that service of process as provided in Section 6 on a party not having its registered office in Switzerland shall be deemed effective service of process on such party.

     13. WAIVER OF JURY TRIAL. EACH PARTY HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS GUARANTEE OR THE TRANSACTIONS CONTEMPLATED HEREBY.

     14. Expenses. The Guarantor agrees to pay all reasonable out-of-pocket expenses (including, without limitation, the reasonable fees and expenses of the Beneficiary’s counsel) incurred by the Beneficiary in connection with the successful enforcement of the rights of the Beneficiary hereunder.

* * * * *

ROCHE HOLDING LTD
By:	/s/ Steve Krognes
	Name:	Steve Krognes
	Title:	Authorized Signatory
By:	/s/ Beat Kraehenmann
	Name:	Beat Kraehenmann
	Title:	Authorized Signatory

Agreed to and accepted by: VENTANA MEDICAL SYSTEMS, INC.
By:	/s/ Christopher M. Gleeson
	Name:	Christopher M. Gleeson
	Title:	President and Chief Executive Officer

EX-99.(E)(16)

Exhibit (e)(16)

AGREEMENT AND PLAN OF MERGER
dated as of
January 21, 2008
among
VENTANA MEDICAL SYSTEMS, INC.,
ROCHE HOLDINGS, INC.
and
ROCKET ACQUISITION CORPORATION

TABLE OF CONTENTS

			Page
ARTICLE 1 The Offer
	Section 1.01.	The Offer		2
	Section 1.02.	Company Action		3
	Section 1.03.	Directors		4
	Section 1.04.	Top-Up Option		5
ARTICLE 2 The Merger
	Section 2.01.	The Merger		6
	Section 2.02.	Conversion of Shares		6
	Section 2.03.	Surrender and Payment		6
	Section 2.04.	Dissenting Shares		7
	Section 2.05.	Stock Options		7
	Section 2.06.	Restricted Shares		8
	Section 2.07.	Performance Units		8
	Section 2.08.	Employee Stock Purchase Plan		8
	Section 2.09.	Compensation Arrangements		8
	Section 2.10.	Adjustments		8
	Section 2.11.	Withholding Rights		8
	Section 2.12.	Lost Certificates		8
ARTICLE 3 The Surviving Corporation
	Section 3.01.	Certificate of Incorporation		9
	Section 3.02.	Bylaws		9
	Section 3.03.	Directors and Officers		9
ARTICLE 4 Representations and Warranties of the Company
	Section 4.01.	Corporate Existence and Power		9
	Section 4.02.	Corporate Authorization		9
	Section 4.03.	Governmental Authorization		10
	Section 4.04.	Non-contravention		10
	Section 4.05.	Capitalization		10
	Section 4.06.	Subsidiaries		11
	Section 4.07.	SEC Filings		11
	Section 4.08.	Financial Statements		12
	Section 4.09.	Disclosure Documents		12

i

			Page
	Section 4.10.	Absence of Certain Changes		12
	Section 4.11.	No Undisclosed Material Liabilities		13
	Section 4.12.	Compliance with Laws and Court Orders		13
	Section 4.13.	Litigation		13
	Section 4.14.	Taxes		13
	Section 4.15.	Labor and Employment		14
	Section 4.16.	Employee Benefit Plans		14
	Section 4.17.	Environmental Matters		16
	Section 4.18.	Material Contracts		17
	Section 4.19.	Intellectual Property		17
	Section 4.20.	Finders’ Fees		18
	Section 4.21.	Opinion of Financial Advisors		18
	Section 4.22.	Anti-takeover Statutes and Rights Agreement		18
ARTICLE 5 Representations and Warranties of Parent
	Section 5.01.	Corporate Existence and Power		19
	Section 5.02.	Corporate Authorization		19
	Section 5.03.	Governmental Authorization		19
	Section 5.04.	Non-contravention		19
	Section 5.05.	Disclosure Documents		20
	Section 5.06.	Finders’ Fees		20
	Section 5.07.	Financing		20
	Section 5.08.	Operations of Merger Subsidiary		20
ARTICLE 6 Covenants of the Company
	Section 6.01.	Conduct of the Company		20
	Section 6.02.	Stockholder Meeting; Proxy Material		22
	Section 6.03.	Access to Information		22
	Section 6.04.	No Solicitation; Change of Recommendation		23
ARTICLE 7 Covenants of Parent
	Section 7.01.	Obligations of Merger Subsidiary		25
	Section 7.02.	Voting of Shares		25
	Section 7.03.	Director and Officer Liability		25
	Section 7.04.	Employee Matters		26
ARTICLE 8 Covenants of Parent and the Company
	Section 8.01.	Reasonable Best Efforts		27
	Section 8.02.	Cooperation		27

ii

			Page
	Section 8.03.	Public Announcements		27
	Section 8.04.	Further Assurances		28
	Section 8.05.	Merger Without Meeting of Stockholders		28
	Section 8.06.	Section 16 Matters		28
	Section 8.07.	Notices of Certain Events		28
	Section 8.08.	Takeover Statutes		28
	Section 8.09.	Litigation		28
	Section 8.10.	Transfer Taxes		29
ARTICLE 9 Conditions to the Merger
	Section 9.01.	Conditions to the Obligations of Each Party		29
ARTICLE 10 Termination
	Section 10.01.	Termination		29
	Section 10.02.	Effect of Termination		30
ARTICLE 11 Miscellaneous
	Section 11.01.	Notices		30
	Section 11.02.	Survival of Representations and Warranties		31
	Section 11.03.	Amendments and Waivers		31
	Section 11.04.	Expenses		32
	Section 11.05.	Disclosure Schedule References and SEC Document References		32
	Section 11.06.	Binding Effect; Benefit; Assignment		32
	Section 11.07.	Governing Law		33
	Section 11.08.	Jurisdiction		33
	Section 11.09.	WAIVER OF JURY TRIAL		33
	Section 11.10.	Counterparts; Effectiveness		33
	Section 11.11.	Entire Agreement		33
	Section 11.12.	Severability		33
	Section 11.13.	Specific Performance		33
ARTICLE 12 Definitions
	Section 12.01.	Definitions		34
	Section 12.02.	Other Definitional and Interpretative Provisions		36

iii

AGREEMENT AND PLAN OF MERGER

AGREEMENT AND PLAN OF MERGER (this “Agreement”) dated as of January 21, 2008, among VENTANA MEDICAL SYSTEMS, INC., a Delaware corporation (the “Company”), ROCHE HOLDINGS, INC., a Delaware corporation (“Parent”), and ROCKET ACQUISITION CORPORATION, a Delaware corporation and a wholly-owned indirect subsidiary of Parent (“Merger Subsidiary”).

WITNESSETH:

WHEREAS, on June 27, 2007 Merger Subsidiary filed a Tender Offer Statement on Schedule TO (together with any amendments or supplements thereto, the “Schedule TO”) with respect to the tender offer by Merger Subsidiary (as such offer has been amended from time to time prior to the date hereof, the “Existing Offer”) to purchase all outstanding shares of common stock, $0.001 par value, of the Company, together with the associated Company Rights (as defined below) for so long as such Company Rights are outstanding (collectively, the “Shares”); and

WHEREAS, the parties hereto have agreed to the acquisition of the Company on the terms and subject to the conditions set forth herein, and Parent has agreed to cause Merger Subsidiary to amend the Existing Offer to reflect such agreement (the “Amended Offer”, and as it may be amended from time to time in accordance with this Agreement, the “Offer”);

NOW, THEREFORE, the parties hereto agree as follows:

ARTICLE 1

The Offer

Section 1.01.  The Offer.  (a) Provided that nothing shall have occurred that would give rise to a right to terminate the Offer pursuant to any of the conditions set forth in Annex I, as promptly as practicable after the date hereof, but in no event later than five Business Days following the public announcement of the execution of this Agreement, Merger Subsidiary shall amend the Offer to (i) increase the purchase price to $89.50 per Share, net to the seller in cash, (ii) provide that the conditions to the Offer shall be as set forth in Annex I and no others, (iii) provide that the expiration date shall be February 7, 2008 and (iv) make such other amendments as are necessary or appropriate to conform to the requirements of this Agreement. The Offer shall be subject to the condition that there shall be validly tendered in accordance with the terms of the Offer prior to the expiration date of the Offer and not withdrawn, a number of Shares that, together with the Shares then owned by Parent and its Affiliates, represents at least a majority of the total number of Shares outstanding on a fully-diluted basis (the “Minimum Condition”) and to the other conditions set forth in Annex I and to no other conditions. Merger Subsidiary expressly reserves the right to waive any of the conditions to the Offer and to make any other changes in the terms of or conditions to the Offer; provided that without the prior consent of the Company (which consent may be granted or withheld by the Company in its sole discretion) (A) the Minimum Condition may not be waived, (B) no change may be made that changes the form of consideration to be paid, decreases the price per Share or the number of Shares sought in the Offer, amends or adds to the conditions to the Offer set forth in Annex I or amends any other term of the Offer in any manner adverse to the stockholders of the Company and (C) the expiration date shall not be extended except as otherwise provided herein. Notwithstanding the foregoing, (x) Merger Subsidiary shall extend the Offer if at the scheduled or extended expiration date of the Offer any of the conditions to the Offer shall not be satisfied or waived, from time to time until such conditions are satisfied or waived; and (y) Merger Subsidiary shall extend the Offer for any period required by any rule, regulation, interpretation or position of the U.S. Securities and Exchange Commission (the “SEC”) or the Nasdaq Global Select Market applicable to the Offer; provided that in no event shall Merger Subsidiary be required to extend the Offer beyond the End Date unless Parent or Merger Subsidiary is not then permitted to terminate this Agreement pursuant to Section 10.01(b)(i), in which case Merger Subsidiary shall be required to extend the Offer beyond the End Date. Following expiration of the Offer, Merger Subsidiary shall, if requested by the Company, or may, in its sole discretion, provide a subsequent offering period (“Subsequent Offering Period”) in accordance with

2

Rule 14d-11 of the 1934 Act. Subject to the foregoing, including the requirements of Rule 14d-11, and upon the terms and subject to the conditions of the Offer, Merger Subsidiary shall, and Parent shall cause it to, accept for payment and pay for, as promptly as practicable after the expiration of the Offer, all Shares (1) validly tendered and not withdrawn pursuant to the Offer and (2) validly tendered in the Subsequent Offering Period (the date on which Shares are first accepted for payment, the “Acceptance Date”).

(b) As promptly as practicable after the date hereof, but in no event later than five Business Days following the public announcement of the execution of this Agreement, Merger Subsidiary shall, and shall cause its Affiliates to, (i) file with the SEC an amendment to the Schedule TO, which shall include a revised offer to purchase and form of letter of transmittal and summary advertisement reflecting the terms and conditions set forth in this Agreement (collectively, together with any amendments or supplements thereto, the “Offer Documents”), and (ii) to the extent required by applicable U.S. federal securities laws, cause the Offer Documents to be disseminated to holders of Shares. Each of Parent, Merger Subsidiary and the Company agrees promptly to correct any information provided by it or any of its Affiliates for use in the Schedule TO and the Offer Documents if and to the extent that such information shall have become false or misleading in any material respect. Merger Subsidiary shall, and shall cause its Affiliates to, use their respective reasonable best efforts to cause the Schedule TO as so corrected to be filed with the SEC and the Offer Documents as so corrected to be disseminated to holders of Shares, in each case as and to the extent required by applicable U.S. federal securities laws. The Company and its counsel shall be given a reasonable opportunity to review and comment (A) on the Schedule TO and the Offer Documents each time before any such document is filed with the SEC and (B) on any correspondence with the SEC (including comment response letters) concerning the Offer or the Offer Documents, and Merger Subsidiary shall give reasonable and good faith consideration to any comments made by the Company and its counsel. Parent and Merger Subsidiary shall provide the Company and its counsel with any written or oral comments Parent, Merger Subsidiary or their respective Affiliates or counsel may receive from the SEC with respect to the Offer Documents promptly, but in no event later than twelve hours, after the receipt of such comments.

Section 1.02.  Company Action.  (a) The Company hereby consents to the Offer and represents that its board of directors (the “Board of Directors”), at a meeting duly called and held has (i) determined that this Agreement and the transactions contemplated hereby, including the Offer and the Merger, are fair to and in the best interests of the Company’s stockholders, (ii) approved and adopted this Agreement and the transactions contemplated hereby, including the Offer and the Merger, and declared this Agreement advisable, in accordance with the requirements of the Delaware General Corporation Law (“Delaware Law”) and (iii) resolved (subject to Section 6.04(b)) to recommend acceptance of the Offer and adoption of this Agreement by the stockholders of the Company.

(b) The Company has been advised that, except as set forth in Section 1.02(b) of the Company Disclosure Schedule (as defined below), as of the date hereof, all of its directors and executive officers who own Shares intend to tender their Shares pursuant to the Offer. The Company shall promptly furnish Parent with a list of its stockholders, mailing labels and any available listing or computer file containing the names and addresses of all record holders of Shares and lists of securities positions of Shares held in stock depositories, in each case true and correct as of the most recent practicable date, and shall provide to Parent such additional information (including updated lists of stockholders, mailing labels and lists of securities positions) as Parent may reasonably request in connection with the Offer.

(c) As promptly as practicable after the amendment to the Schedule TO is filed with the SEC pursuant to the first sentence of Section 1.01(b), but in no event later than five Business Days following the public announcement of the execution of this Agreement, the Company shall file with the SEC and, to the extent required by applicable U.S. securities laws, disseminate to holders of Shares an amendment to the Solicitation/Recommendation Statement on Schedule 14D-9 filed by the Company on July 11, 2007 (together with any amendments or supplements thereto, the “Schedule 14D-9”) that, subject to Section 6.04(b), shall reflect the recommendations of the Board of Directors referred to above. Each of the Company, Parent and Merger Subsidiary agrees promptly to correct any information provided by it or any of its Affiliates for use in the Schedule 14D-9 if and to the extent that it shall have become false or misleading in any material respect. The Company shall cause the Schedule 14D-9 as so corrected to be filed with the SEC and to be disseminated to

3

holders of Shares, in each case as and to the extent required by applicable U.S. federal securities laws. Parent, Merger Subsidiary and their counsel shall be given a reasonable opportunity to review and comment (A) on the Schedule 14D-9 each time before it is filed with the SEC and (B) on any correspondence with the SEC (including comment response letters) concerning the Schedule 14D-9, and the Company shall give reasonable and good faith consideration to any comments made by Parent, Merger Subsidiary and their counsel. The Company shall provide Parent and Merger Subsidiary and their counsel with any written or oral comments the Company or its counsel may receive from the SEC with respect to the Schedule 14D-9 promptly, but in no event later than twelve hours, after the receipt of such comments.

Section 1.03.  Directors.  (a) Effective upon the acceptance for payment of any Shares pursuant to the Offer, Parent shall be entitled to designate the number of directors, rounded up to the next whole number, on the Board of Directors that equals the product of (i) the total number of directors on the Board of Directors (giving effect to the election of any additional directors pursuant to this Section 1.03) and (ii) the percentage that the number of Shares beneficially owned by Parent and its Affiliates (including Shares accepted for payment) bears to the total number of Shares outstanding, and the Company shall use its reasonable best efforts to take all action necessary to cause Parent’s designees to be elected or appointed to the Board of Directors, including increasing the number of directors and seeking and accepting resignations of incumbent directors. At such time, the Company shall also use its reasonable best efforts to cause individuals designated by Parent to constitute the number of members, rounded up to the next whole number, on (A) each committee of the Board of Directors and (B) each board of directors of each Subsidiary of the Company (and each committee thereof) that, in each case, represents the same percentage as such individuals represent on the Board of Directors. Notwithstanding the foregoing, following the election or appointment of Parent’s designees pursuant to this Section 1.03(a) and until the Effective Time, the Board of Directors shall at all times include, and the Company, Parent and Merger Subsidiary shall cause the Board of Directors to at all times include, at least three Continuing Directors and each committee of the Board of Directors and the board of directors of each Subsidiary of the Company shall at all times include, and the Company, Parent and Merger Subsidiary shall cause each committee of the Board of Directors and the board of directors of each Subsidiary of the Company to at all times include, at least one Continuing Director. A “Continuing Director” shall mean a person who is a member of the Board of Directors as of the date hereof or a person selected by the Continuing Directors then in office. If the number of Continuing Directors is reduced to below three prior to the Effective Time, any remaining Continuing Directors (or Continuing Director, if there shall be only one remaining) shall be entitled to designate a person to fill such vacancy who is not an officer, director, stockholder or designee of Parent or any of its Affiliates and who shall be deemed to be a Continuing Director for all purposes of this Agreement, or, if no Continuing Directors then remain, the other directors shall designate three persons to fill such vacancies who are not officers, directors, stockholders or designees of Parent or any of its Affiliates, and such persons shall be deemed to be Continuing Directors for all purposes of this Agreement.

(b) The Company’s obligations to appoint Parent’s designees to the Board of Directors shall be subject to Section 14(f) of the 1934 Act and Rule 14f-1 promulgated thereunder. Subject to applicable Laws, the Company shall promptly take all actions required pursuant to Section 14(f) and Rule 14f-1 in order to fulfill its obligations under this Section 1.03, including mailing to stockholders of the Company the information required by Section 14(f) and Rule 14f-1 as is necessary to enable Parent’s designees to be elected or designated to the Board of Directors (provided that Parent or Merger Subsidiary shall have provided to the Company on a timely basis all information with respect to itself and its nominees, officers, directors and Affiliates required by Section 14(f) and Rule 14f-1). Parent shall supply to the Company in writing and be solely responsible for any information with respect to itself and its nominees, officers, directors and Affiliates required by Section 14(f) and Rule 14f-1.

(c) Following the election or appointment of Parent’s designees pursuant to Section 1.03(a) and until the Effective Time, the approval of a majority of the Continuing Directors shall be required to authorize (and such authorization shall constitute the authorization of the Board of Directors and no other action on the part of the Company, including any action by any other director of the Company, shall be required) (i) any amendment or termination of this Agreement by the Company, (ii) any agreement between the Company and any of its Subsidiaries, on the one hand, and Parent, Merger Subsidiary or any of their respective Affiliates (other than

4

the Company and its Subsidiaries), on the other hand, (iii) the taking of any action by the Company or any of its Subsidiaries that would prevent or would materially delay the consummation of the Merger, (iv) any extension of time for performance of any obligation or action hereunder by Parent or Merger Subsidiary or (v) any waiver of any of the Company’s rights or remedies under this Agreement.

Section 1.04.  Top-Up Option.  (a) Subject to Sections 1.04(b) and 1.04(c), the Company grants to Merger Subsidiary an option, for so long as this Agreement has not been terminated pursuant to the provisions hereof (the “Top-Up Option”), to purchase from the Company, up to the number of authorized and unissued Shares, the number of Shares that, when added to the number of Shares owned by Merger Subsidiary at the time of exercise of the Top-Up Option, constitutes one Share more than 90% of the Shares that would be outstanding immediately after the issuance of all Shares to be issued upon exercise of the Top-Up Option, calculated on a fully-diluted basis (the Shares to be issued upon exercise of the Top-Up Option, the “Top-Up Shares”).

(b) The Top-Up Option may be exercised by Merger Subsidiary in accordance with Section 1.04(c), in whole or in part, only once, at any time during the 10 Business Day period following the Acceptance Date, or if any Subsequent Offering Period is provided, during the 10 Business Day period following the expiration date of such Subsequent Offering Period, and only if Merger Subsidiary shall own as of such time less than 90% of the outstanding Shares; provided that notwithstanding anything in this Agreement to the contrary, the Top-Up Option shall not be exercisable to the extent (i) the issuance of the Shares upon exercise of the Top-Up Option would require approval of the Company’s stockholders under the rules and regulations of the Nasdaq Global Select Market or (ii) the number of Shares issuable upon exercise of the Top-Up Option would exceed the number of authorized but unissued and unreserved Shares. The aggregate purchase price payable for the Top-Up Shares being purchased by Merger Subsidiary pursuant to the Top-Up Option shall be determined by multiplying the number of such Shares by an amount in cash equal to the price paid for each Share in the Offer, without interest. Such purchase price shall be payable in cash by Merger Subsidiary.

(c) In the event Merger Subsidiary wishes to exercise the Top-Up Option, Merger Subsidiary shall deliver to the Company a notice (the “Top-Up Notice”) setting forth (i) the number of Top-Up Shares that Merger Subsidiary intends to purchase pursuant to the Top-Up Option and (ii) the place and time at which the closing of the purchase of such Top-Up Shares by Merger Subsidiary is to take place. The Top-Up Notice shall also include an undertaking signed by Parent and Merger Subsidiary that, as promptly as practicable following such exercise of the Top-Up Option, Merger Subsidiary intends to (and Merger Subsidiary shall, and Parent shall cause Merger Subsidiary to, as promptly as practicable after such exercise) consummate the Merger in accordance with Section 253 of Delaware Law as contemplated by Section 8.05. At the closing of the purchase of the Top-Up Shares, Parent and Merger Subsidiary shall cause to be delivered to the Company the consideration required to be delivered in exchange for the Top-Up Shares, and the Company shall cause to be issued to Merger Subsidiary a certificate representing the Top-Up Shares. The parties hereto agree to use their reasonable best efforts to cause the closing of the purchase of the Top-Up Shares to occur on the same day that the Top-Up Notice is deemed received by the Company pursuant to Section 11.01, and if not so consummated on such day, as promptly thereafter as possible. The parties further agree to use their reasonable best efforts to cause the Merger to be consummated in accordance with Section 253 of Delaware Law as contemplated by Section 8.05 as close in time as possible to (including, to the extent possible, on the same day as) the issuance of the Top-Up Shares.

(d) Parent and Merger Subsidiary understand that the Top-Up Shares will not be registered under the 1933 Act and will be issued in reliance upon an exemption thereunder for transactions not involving a public offering. Each of Parent and Merger Subsidiary represents, warrants and agrees that the Top-Up Option is being, and the Top-Up Shares will be, acquired by Merger Subsidiary for the purpose of investment and not with a view to or for resale in connection with any distribution thereof within the meaning of the 1933 Act. Any certificates evidencing Top-Up Shares may include any legends required by applicable securities laws.

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ARTICLE 2

The Merger

Section 2.01.  The Merger.  (a) At the Effective Time, Merger Subsidiary shall be merged (the “Merger”) with and into the Company in accordance with Delaware Law, whereupon the separate existence of Merger Subsidiary shall cease, and the Company shall be the surviving corporation (the “Surviving Corporation”).

(b) As soon as practicable (and in no event later than the third Business Day) after satisfaction or, to the extent permitted hereunder, waiver of all conditions to the Merger set forth in Article 9, the Company and Merger Subsidiary shall file a certificate of merger (or, if the Merger is consummated pursuant to Section 253 of Delaware Law, a certificate of ownership and merger) with the Delaware Secretary of State and make all other filings or recordings required by Delaware Law and this Agreement in connection with the Merger. The Merger shall become effective at such time (the “Effective Time”) as the certificate of merger (or, if the Merger is to be consummated pursuant to Section 253 of Delaware Law, the certificate of ownership and merger) is duly filed with the Delaware Secretary of State or at such later time as is permitted by applicable Law and specified in the certificate of merger.

(c) At the Effective Time, the separate existence of Merger Subsidiary shall cease, and from and after the Effective Time, the Surviving Corporation shall possess all the rights, powers, privileges and franchises and be subject to all of the obligations, liabilities, debts, duties, restrictions and disabilities of the Company and Merger Subsidiary, all as provided under Delaware Law.

Section 2.02.  Conversion of Shares.  At the Effective Time, by virtue of the Merger and without any action on the part of Parent, Merger Subsidiary, the Company or the holders of securities of Parent, Merger Subsidiary or the Company:

(a) except as otherwise provided in Section 2.02(b), Section 2.02(c) or Section 2.04, each Share outstanding immediately prior to the Effective Time shall be converted into the right to receive an amount in cash equal to the price paid for each Share in the Offer, without interest (the “Merger Consideration”);

(b) each Share held by the Company as treasury stock or by Parent or any of its Subsidiaries immediately prior to the Effective Time shall be canceled, and no payment shall be made with respect thereto;

(c) each Share held by a Subsidiary of the Company immediately prior to the Effective Time shall be converted into such number of shares of stock of the Surviving Corporation such that each such Subsidiary owns the same percentage of the outstanding capital stock of Surviving Corporation immediately following the Effective Time as such Subsidiary owned in the Company immediately prior to the Effective Time; and

(d) each share of common stock of Merger Subsidiary outstanding immediately prior to the Effective Time shall be converted into and become one share of common stock of the Surviving Corporation with the same rights, powers and privileges as the shares so converted and shall constitute the only outstanding shares of capital stock of the Surviving Corporation (except for any such shares resulting from the conversion of Shares pursuant to Section 2.02(c)).

Section 2.03.  Surrender and Payment.  (a) Prior to the Effective Time, Parent shall appoint an agent reasonably acceptable to the Company (the “Exchange Agent”) for the purpose of exchanging for the Merger Consideration (i) certificates representing Shares (the “Certificates”) or (ii) uncertificated Shares (the “Uncertificated Shares”). Merger Subsidiary or one of its Affiliates shall deposit with the Exchange Agent, as needed from time to time, the Merger Consideration to be paid in respect of the Certificates and the Uncertificated Shares. Promptly after the Effective Time, Parent shall send, or shall cause the Exchange Agent to send, to each holder of Shares at the Effective Time a letter of transmittal and instructions for use in such exchange (which shall specify that the delivery shall be effected, and risk of loss and title shall pass, only upon proper delivery of the Certificates or transfer of the Uncertificated Shares to the Exchange Agent).

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(b) Each holder of Shares that have been converted into the right to receive the Merger Consideration shall be entitled to receive, upon (i) surrender to the Exchange Agent of a Certificate, together with a properly completed letter of transmittal, or (ii) receipt of an “agent’s message” by the Exchange Agent (or such other evidence, if any, of transfer as the Exchange Agent may reasonably request) in the case of a book-entry transfer of Uncertificated Shares, the Merger Consideration payable for each Share represented by a Certificate or for each Uncertificated Share. Until so surrendered or transferred, as the case may be, each such Certificate or Uncertificated Share shall represent after the Effective Time for all purposes only the right to receive the Merger Consideration.

(c) If any portion of the Merger Consideration is to be paid to a Person other than the Person in whose name the surrendered Certificate or Uncertificated Share is registered, it shall be a condition to such payment that (i) either such Certificate shall be properly endorsed or shall otherwise be in proper form for transfer or such Uncertificated Share shall be properly transferred and (ii) the Person requesting such payment shall pay to the Exchange Agent any transfer or other Taxes required as a result of such payment to a Person other than the registered holder of such Certificate or Uncertificated Share or establish to the satisfaction of the Exchange Agent that such Tax has been paid or is not payable.

(d) After the Effective Time, there shall be no further registration of transfers of Shares. If, after the Effective Time, Certificates or Uncertificated Shares are presented to the Surviving Corporation, they shall be canceled and exchanged for the Merger Consideration provided for, and in accordance with the procedures set forth, in this Article 2.

(e) Any portion of the Merger Consideration made available to the Exchange Agent pursuant to Section 2.03(a) (and any interest or other income earned thereon) that remains unclaimed by the holders of Shares six months after the Effective Time shall be returned to the Surviving Corporation or one of its Affiliates upon demand, and any such holder who has not exchanged such Shares for the Merger Consideration in accordance with this Section 2.03 prior to that time shall thereafter look only to the Surviving Corporation for payment of the Merger Consideration in respect of such Shares without any interest thereon. Notwithstanding the foregoing, neither the Surviving Corporation nor any of its Affiliates shall be liable to any holder of Shares for any amount paid to a public official pursuant to applicable abandoned property, escheat or similar laws.

(f) Any portion of the Merger Consideration made available to the Exchange Agent pursuant to Section 2.03(a) to pay for Shares for which appraisal rights have been perfected shall be returned to the Surviving Corporation or one of its Affiliates, upon demand.

Section 2.04.  Dissenting Shares.  Notwithstanding Section 2.02, Shares outstanding immediately prior to the Effective Time and held by a holder who has not voted in favor of the Merger or consented thereto in writing and who has properly demanded appraisal for such Shares in accordance with Delaware Law shall not be converted into a right to receive the Merger Consideration, unless and until such holder fails to perfect, withdraws (in accordance with Delaware Law) or otherwise loses the right to appraisal. If, after the Effective Time, such holder fails to perfect, withdraws (in accordance with Delaware Law) or loses the right to appraisal, such Shares shall be treated as if they had been converted as of the Effective Time into a right to receive the Merger Consideration. The Company shall give Parent prompt notice of any demands received by the Company for appraisal of Shares, and Parent shall have the right to participate in all negotiations and proceedings with respect to such demands. Except with the prior written consent of Parent, the Company shall not make any payment with respect to, or offer to settle or settle, any such demands.

Section 2.05.  Stock Options.   At the Effective Time, each then-outstanding option to purchase Shares granted under any stock option or compensation plan or arrangement of the Company (a “Company Stock Option”), whether or not vested or exercisable, shall vest and be canceled, and, in exchange therefor, the Surviving Corporation shall pay to each former holder of any such Company Stock Option at or promptly after the Effective Time an amount in cash equal to the product of (a) the excess, if any, of the Merger Consideration over the applicable exercise price per Share of such Company Stock Option and (b) the number of Shares such holder could have purchased (assuming full vesting of such Company Stock Option) had such holder exercised such Company Stock Option in full immediately prior to the Effective Time.

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Section 2.06.  Restricted Shares.  At the Effective Time, each then-outstanding restricted Share granted under any equity or compensation plan or arrangement of the Company (a “Company Restricted Share”) shall vest (and all restrictions thereon shall immediately lapse) and shall be converted into the right to receive the Merger Consideration in accordance with Section 2.02(a).

Section 2.07.  Performance Units.  At the Effective Time, each then-outstanding performance unit granted under any equity or compensation plan or arrangement of the Company (a “Company Performance Unit”), whether or not vested, shall vest and be canceled, and, in exchange therefor, the Surviving Corporation shall pay to each former holder of any such cancelled Company Performance Unit at or promptly after the Effective Time an amount in cash equal to the product of the Merger Consideration and the number of Shares subject to or related to such Company Performance Unit.

Section 2.08.  Employee Stock Purchase Plan.  The Company shall take all action that is necessary to (a) suspend all payroll deductions and cause the exercise of each outstanding purchase right under the Company’s 2005 Employee Stock Purchase Plan (the “Company ESPP”) not later than the initial scheduled expiration of the Amended Offer; (b) provide that no further purchase period or offering period shall commence under the Company ESPP following that date; and (c) immediately prior to and effective as of the Effective Time and subject to the consummation of the Merger, terminate the Company ESPP.

Section 2.09.  Compensation Arrangements.  Prior to the Acceptance Date, to the extent necessary, the Company (acting through the Compensation Committee of the Board of Directors) will take all steps that may be necessary or reasonably advisable to cause any employee agreement, plan or arrangement pursuant to which consideration is payable to any officer, director or employee to be approved by the Compensation Committee of the Board of Directors (comprised solely of “independent directors” determined in accordance with the requirements of Rule 14d-10(d)(2) under the 1934 Act and the instructions thereto) as an “employment compensation, severance or other employee benefit arrangement” within the meaning of Rule 14d-10(d)(2) and to satisfy the requirements of the non-exclusive safe harbor set forth in Rule 14d-10(d).

Section 2.10.  Adjustments.  If, during the period between the date of this Agreement and the Effective Time, the outstanding Shares shall be changed into a different number of shares or a different class (including by reason of any reclassification, recapitalization, stock split or combination, exchange or readjustment of Shares, or stock dividend thereon with a record date during such period, but excluding any change that results from any exercise of Company Stock Options), the cash payable pursuant to the Offer, the Merger Consideration and any other amounts payable pursuant to this Agreement shall be appropriately adjusted.

Section 2.11.  Withholding Rights.  Notwithstanding anything else contained herein to the contrary, each of the Surviving Corporation and Parent shall be entitled to deduct and withhold from the consideration otherwise payable to any Person pursuant to Article 1 and Article 2 such amounts as it is required to deduct and withhold with respect to the making of such payment under any provision of Tax law. If the Surviving Corporation or Parent, as the case may be, so withholds amounts, such amounts shall be treated for all purposes of this Agreement as having been paid to the Person in respect of which the Surviving Corporation or Parent, as the case may be, made such deduction and withholding.

Section 2.12.  Lost Certificates.  If any Certificate shall have been mutilated, lost, stolen or destroyed, upon the making of an affidavit of that fact by the Person claiming such Certificate to be mutilated, lost, stolen or destroyed, the completion of the letter of transmittal by such Person and, if required by the Surviving Corporation, the posting by such Person of a bond, in such reasonable amount as the Surviving Corporation may direct, as indemnity against any claim that may be made against it with respect to such Certificate, the Exchange Agent shall pay, in exchange for such mutilated, lost, stolen or destroyed Certificate, the Merger Consideration to be paid in respect of the Shares represented by such Certificate as contemplated by this Article 2.

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ARTICLE 3

The Surviving Corporation

Section 3.01.  Certificate of Incorporation.  The certificate of incorporation of the Company in effect at the Effective Time shall, subject to the provisions of Section 7.03 hereof, be the certificate of incorporation of the Surviving Corporation until amended in accordance with Delaware Law.

Section 3.02.  Bylaws.  The bylaws of Merger Subsidiary in effect at the Effective Time shall, subject to the provisions of Section 7.03 hereof, be the bylaws of the Surviving Corporation until amended in accordance with Delaware Law.

Section 3.03.  Directors and Officers.  From and after the Effective Time, until successors are duly elected or appointed and qualified in accordance with Delaware Law, (a) the directors of Merger Subsidiary at the Effective Time shall be the directors of the Surviving Corporation and (b) the officers of the Company at the Effective Time shall be the officers of the Surviving Corporation.

ARTICLE 4

Representations and Warranties of the Company

Except as disclosed in (a) the Company SEC Documents filed with the SEC prior to the date hereof (the “Filed SEC Documents”) or (b) the disclosure schedule delivered by the Company to Parent and Merger Subsidiary prior to or simultaneously with the execution of this Agreement (the “Company Disclosure Schedule”), the Company represents and warrants to Parent that:

Section 4.01.  Corporate Existence and Power.  The Company is a corporation duly incorporated, validly existing and in good standing under the laws of the State of Delaware and has all corporate powers and all governmental licenses, authorizations, permits, consents and approvals required to carry on its business in substantially the same manner as now conducted, except for those licenses, authorizations, permits, consents and approvals (a) set forth in Section 4.01 of the Company Disclosure Schedule or (b) the absence of which would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect. The Company is duly qualified to do business as a foreign corporation and is in good standing in each jurisdiction where such qualification is necessary, except for those jurisdictions where failure to be so qualified would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect. The Company has heretofore made available to Parent true and complete copies of the certificate of incorporation and bylaws of the Company as currently in effect.

Section 4.02.  Corporate Authorization.  (a) The execution, delivery and performance by the Company of this Agreement and the consummation by the Company of the transactions contemplated hereby are within the Company’s corporate powers and, except for any required approval of the Company’s stockholders in connection with the consummation of the Merger, have been duly authorized by all necessary corporate action on the part of the Company. The affirmative vote of the holders of a majority of the outstanding Shares (if required by Delaware Law) is the only vote of the holders of any of the Company’s capital stock required in connection with the consummation of the Merger (the “Company Stockholder Approval”) This Agreement constitutes a valid and binding agreement of the Company.

(b) At a meeting duly called and held, the Board of Directors has (i) determined that this Agreement and the transactions contemplated hereby are fair to and in the best interests of the Company’s stockholders, (ii) approved and adopted this Agreement and the transactions contemplated hereby, including the Offer and the Merger, and declared this Agreement advisable, in accordance with the requirements of Delaware Law and (iii) resolved (subject to Section 6.04(b)) to recommend acceptance of the Offer and adoption of this Agreement by the stockholders of the Company (the “Company Board Recommendation”).

Section 4.03.  Governmental Authorization.  The execution, delivery and performance by the Company of this Agreement and the consummation by the Company of the transactions contemplated hereby require no action by or in respect of, or filing with, any Governmental Authority, other than (a) the filing of a certificate

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of merger (or certificate of ownership and merger) with respect to the Merger with the Delaware Secretary of State, (b) compliance with any applicable Antitrust Laws, (c) compliance with any applicable requirements of the 1934 Act and any other applicable U.S. state or federal securities laws, (d) compliance with any applicable rules and regulations of the Nasdaq Global Select Market and (e) any actions or filings the absence of which would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

Section 4.04.  Non-contravention.  Except as set forth in Section 4.04 of the Company Disclosure Schedule, the execution, delivery and performance by the Company of this Agreement and the consummation by the Company of the transactions contemplated hereby do not and will not (a) contravene, conflict with, or result in any violation or breach of any provision of the certificate of incorporation or bylaws of the Company, (b) assuming compliance with the matters referred to in Section 4.03, contravene, conflict with, or result in a violation or breach of any provision of applicable Law or any judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction, (c) require any consent or other action by any Person under, constitute a default, or an event that, with or without notice or lapse of time or both, could become a default, under, or cause or permit the termination, cancellation, acceleration or other change of any right or obligation or the loss of any benefit to which the Company or any of its Subsidiaries is entitled under any provision of any agreement or other instrument binding upon the Company or any of its Subsidiaries or any license, franchise, permit, certificate, approval or other similar authorization affecting, or relating in any way to, the assets or business of the Company and its Subsidiaries or (d) result in the creation or imposition of any Lien on any asset of the Company or any of its Subsidiaries, except, in the case of clauses (b) through (d), for such matters as would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

Section 4.05.  Capitalization.  (a) The authorized capital stock of the Company consists of 100,000,000 Shares and 5,000,000 shares of preferred stock. As of January 20, 2008 there were outstanding 34,844,346 Shares (of which an aggregate of 16,150 are Company Restricted Shares), no shares of preferred stock, Company Stock Options to purchase an aggregate of 4,895,184 Shares (of which options to purchase an aggregate of 3,922,382 Shares were exercisable) and Company Performance Units with respect to 43,104 Shares. All outstanding shares of capital stock of the Company have been, and all shares that may be issued upon exercise of Company Stock Options or delivered in settlement of Company Performance Units will be, when issued in accordance with the respective terms thereof, duly authorized and validly issued and fully paid and nonassessable and free of preemptive rights. Section 4.05 of the Company Disclosure Schedule contains a list of (i) each outstanding Company Stock Option, including the holder, date of grant, exercise price, number of Shares subject thereto and the number of such Shares that have vested and (ii) all outstanding Company Restricted Shares and Company Performance Units, including with respect to each such share or unit, the holder, date of grant and number vested, and such list is complete and accurate in all material respects.

(b) Except for the Company’s obligations under the Rights Agreement and the Company Rights issued pursuant thereto, except as set forth in this Section 4.05 and for changes since January 20, 2008 resulting from the exercise of Company Stock Options outstanding on such date and the purchase of Shares pursuant to the Company ESPP in accordance with its terms as in effect on the date hereof, there are no outstanding (i) shares of capital stock of or other voting securities or ownership interests in the Company or (ii) options or other rights to acquire from the Company, or other obligation of the Company to issue, any capital stock or other voting securities or ownership interests in, or any securities convertible into or exchangeable or exercisable for capital stock or other voting securities or ownership interests in, the Company (the items in clauses (i) and (ii) being referred to collectively as the “Company Securities”). There are no outstanding obligations of the Company or any of its Subsidiaries to repurchase, redeem or otherwise acquire any of the Company Securities.

(c) Except as set forth in Section 4.05 of the Company Disclosure Schedule, none of (i) the Shares or (ii) Company Securities are owned by any Subsidiary of the Company.

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Section 4.06.  Subsidiaries.   (a) Each Subsidiary of the Company is a corporation duly incorporated, validly existing and in good standing under the laws of its jurisdiction of incorporation, has all corporate powers and all governmental licenses, authorizations, permits, consents and approvals required to carry on its business in substantially the same manner as now conducted, except for those licenses, authorizations, permits, consents and approvals the absence of which would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect. Each such Subsidiary is duly qualified to do business as a foreign corporation and is in good standing in each jurisdiction where such qualification is necessary, except for those jurisdictions where failure to be so qualified would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect. Except as set forth in Section 4.06(a) of the Company Disclosure Schedule, all Subsidiaries of the Company and their respective jurisdictions of incorporation are identified in the Company 10-K. Except for Subsidiaries of the Company, neither the Company nor any of its Subsidiaries owns more than 5% of the outstanding equity interests in any Person.

(b) Except as set forth in Section 4.06(b) of the Company Disclosure Schedule, all of the outstanding capital stock of or other voting securities or ownership interests in each Subsidiary of the Company is owned by the Company, directly or indirectly, free and clear of any Lien and free of any other limitation or restriction (including any restriction on the right to vote, sell or otherwise dispose of such capital stock or other voting securities or ownership interests). Except as set forth in the preceding sentence, there are no outstanding (i) shares of capital stock of or other voting securities or ownership interests in any Subsidiary of the Company or (ii) options or other rights to acquire from the Company or any of its Subsidiaries, or other obligation of the Company or any of its Subsidiaries to issue, any capital stock of or other voting securities or ownership interests in, or any securities convertible into or exchangeable or exercisable for any capital stock of or other voting securities or ownership interests in, any Subsidiary of the Company (the items in clauses (i) and (ii) being referred to collectively as the “Company Subsidiary Securities”). There are no outstanding obligations of the Company or any of its Subsidiaries to repurchase, redeem or otherwise acquire any of the Company Subsidiary Securities.

Section 4.07.  SEC Filings.   (a) The Company has made available to Parent (i) the Company’s annual report on Form 10-K for the year ended December 31, 2006 (the “Company 10-K”), (ii) its quarterly reports on Form 10-Q for the quarters ended March 31, 2007, June 30, 2007 and September 30, 2007, (iii) its proxy or information statements relating to meetings of the stockholders of the Company held (or actions taken without a meeting by such stockholders) since December 31, 2006, and (iv) all of its other reports, statements, schedules and registration statements filed by the Company with the SEC since December 31, 2006 (the documents referred to in this Section 4.07(a), collectively, the “Company SEC Documents”). As of its date (or, if amended prior to the date hereof, as of the date of the last such amendment), each Company SEC Document complied as to form in all material respects with the applicable requirements of the 1933 Act and the 1934 Act, as the case may be, and did not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements made therein, in the light of the circumstances under which they were made, not misleading.

(b) The Company has established and maintains disclosure controls and procedures (as defined in Rule 13a-15 under the 1934 Act). Such disclosure controls and procedures are designed to ensure that information required to be disclosed in the Company’s periodic reports filed or submitted under the 1934 Act is recorded, processed, summarized and reported within the required time periods. Such disclosure controls and procedures are effective in timely alerting the Company’s principal executive officer and principal financial officer to material information required to be included in the Company’s periodic reports required under the 1934 Act.

(c) The Company has established and maintains a system of internal control over financial reporting (as defined in Rule 13a-15 under the 1934 Act). Such internal controls are designed to provide reasonable assurance regarding the reliability of the Company’s financial reporting and the preparation of Company financial statements for external purposes in accordance with GAAP. The Company has disclosed, based on its most recent evaluation of internal controls prior to the date hereof, to the Company’s auditors and audit committee (i) any significant deficiencies and material weaknesses in the design or operation of internal controls which are reasonably likely to adversely affect the Company’s ability to record, process,

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summarize and report financial information and (ii) any fraud, whether or not material, that involves management or other employees who have a significant role in internal controls. The Company has made available to Parent a summary of any such disclosure made by management to the Company’s auditors and audit committee since January 1, 2005.

(d) Since January 1, 2005, each Company SEC Document that was required to be accompanied by the certifications required to be filed or submitted by the Company’s principal executive officer and principal financial officer pursuant to the Sarbanes-Oxley Act was accompanied by such certification and, at the time of filing or submission of each such certification, such certification was true and accurate and complied with the Sarbanes-Oxley Act.

(e) There are no outstanding loans or other extensions of credit made by the Company or any of its Subsidiaries to any executive officer (as defined in Rule 3b-7 under the 1934 Act) or director of the Company. The Company has complied, since January 1, 2005, in all material respects with the Sarbanes-Oxley Act.

Section 4.08.  Financial Statements.  The consolidated financial statements of the Company (including all related notes and schedules) included in the Company SEC Documents fairly present in all material respects the consolidated financial position of the Company and its consolidated Subsidiaries as of the dates thereof and the consolidated results of their operations and their cash flows for the periods then ended (subject, in the case of unaudited interim financial statements, to normal year-end audit adjustments and the absence of notes as permitted by Form 10-Q) in conformity with United States generally accepted accounting principles (“GAAP”) applied on a consistent basis (except as may be indicated in the notes thereto). For purposes of this Agreement, “Company Balance Sheet” means the consolidated balance sheet of the Company as set forth in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2007, and “Company Balance Sheet Date” means September 30, 2007.

Section 4.09.  Disclosure Documents.   (a) Each document required to be filed by the Company with the SEC or required to be distributed or otherwise disseminated to the Company’s stockholders in connection with the transactions contemplated by this Agreement (the “Company Disclosure Documents”), including the Schedule 14D-9, and any amendments or supplements thereto, when filed, distributed or disseminated, as applicable, will comply as to form in all material respects with the applicable requirements of the 1934 Act.

(b) The information with respect to the Company or any of its Subsidiaries that the Company furnishes to Parent in writing specifically for use in the Schedule TO and the Offer Documents, at the time of the filing of the Schedule TO or any amendment or supplement thereto, at the time of any distribution or dissemination of the Offer Documents and at the time of the consummation of the Offer, will not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements made therein, in the light of the circumstances under which they were made, not misleading.

Section 4.10.  Absence of Certain Changes.   Except as set forth in Section 4.10 of the Company Disclosure Schedule, since the Company Balance Sheet Date, the business of the Company and its Subsidiaries has been conducted in the ordinary course consistent with past practices and there has not been (a) any event, occurrence, development or state of circumstances or facts that has had or would reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect; (b) any amendment to the articles of incorporation or bylaws of the Company; (c) any split, combination or reclassification of any shares of the Company’s capital stock or declaration, setting aside or payment of any dividend or other distribution (whether in cash, stock or property or any combination thereof) in respect of the Company’s capital stock, or redemption, repurchase or other acquisition or offer to redeem, repurchase or otherwise acquire any Company Securities; (d) any sale, assignment, license or other transfer of any Necessary Intellectual Property or Company Intellectual Property (or any rights therein) or acquisition of any material Intellectual Property other than in the ordinary course of business consistent with past practices; (e) except as required by the terms of an applicable plan or agreement then in effect or as required or deemed advisable pursuant to applicable Law and except as would not result in an expense greater than $25,000 in the aggregate, (i) any increase in compensation, bonuses or other benefits payable to any director or executive officer or, except in the ordinary

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course of business consistent with past practices, other employee of the Company or any of its Subsidiaries or (ii) any entering into, adoption or amendment in any material respect of any employment, change of control, severance, compensation, bonus, profit-sharing, stock option or other stock related rights or other forms of incentive or deferred compensation, retirement benefits or other benefit agreement, plan, arrangement or policy applicable to any director or executive officer or, except in the ordinary course of business consistent with past practices, any other employee of the Company or any of its Subsidiaries; or (f) any resolution, commitment or agreement to take any of the actions described in clauses (b) through (e) of this Section 4.10.

Section 4.11.  No Undisclosed Material Liabilities.  There are no liabilities or obligations of the Company or any of its Subsidiaries of any kind whatsoever, whether accrued, contingent, absolute, determined, determinable or otherwise, other than:

(a) liabilities or obligations disclosed or provided for in the Company Balance Sheet or in the Filed SEC Documents;

(b) liabilities or obligations incurred in the ordinary course of business consistent with past practices;

(c) liabilities or obligations that would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect; and

(d) liabilities or obligations incurred in connection with the transactions contemplated by this Agreement.

Section 4.12.  Compliance with Laws and Court Orders.  Except as set forth in Section 4.12 of the Company Disclosure Schedule, the Company and each of its Subsidiaries is (and since December 31, 2005 has been) in compliance with, and to the knowledge of the Company is not under investigation with respect to, and has not been threatened to be charged with, or given notice of any violation of, any provision of applicable Law or any judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction, except for such matters as would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

This Section 4.12 excludes the subject matters covered by Sections 4.07, 4.14, 4.17 and 4.19.

Section 4.13.  Litigation.  Except as set forth in Section 4.13 of the Company Disclosure Schedule, there is no action, suit, investigation or proceeding pending against, or, to the knowledge of the Company, threatened against or otherwise affecting, the Company, any of its Subsidiaries, any of their respective properties or, to the knowledge of the Company, any present or former officer, director or employee of the Company or any of its Subsidiaries, that would reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

Section 4.14.  Taxes.  (a) Except as set forth in Section 4.14(a) of the Company Disclosure Schedule, each Tax Return required to be filed with any Taxing Authority by, or on behalf of, the Company or any of its Subsidiaries has been timely filed and each such Tax Return is true and complete in all respects, except where the failure to timely file or to be true and complete would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect.

(b) Except as set forth in Section 4.14(b) of the Company Disclosure Schedule and except for such matters as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, the Company and each of its Subsidiaries has paid (or has had paid on its behalf) or has withheld and remitted to the appropriate Taxing Authority all Taxes shown as due and payable on all Tax Returns that have been filed.

(c) The consolidated federal income Tax Returns for the affiliated group of which the Company is the common parent through the Tax year ended December 31, 2004 have been examined and the examinations have been closed or are Tax Returns with respect to which the applicable period for assessment under Law, after giving effect to extensions or waivers, has expired.

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(d) Except as set forth in Section 4.14(d) of the Company Disclosure Schedule, there is no audit, examination, or proceeding by any Taxing Authority now pending or, to the Company’s knowledge, threatened against or with respect to the Company or its Subsidiaries in respect of any Tax that would reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

(e) During the two-year period ending on the date hereof, neither the Company nor any of its Subsidiaries has constituted either a “distributing corporation” or a “controlled corporation” (within the meaning of Section 355(a)(1)(A) of the Code).

(f) Neither the Company nor any of its Subsidiaries has been required to disclose to the Internal Revenue Service that it has participated in a “listed transaction” within the meaning of Treasury Regulation Section 1.6011-4(b).

(g) For purposes of this Agreement:

“Tax” (and, with correlative meaning, “Taxes”) means (i) all taxes, charges, fees, duties, levies, penalties or other assessments, including income, gross receipts, excise, real and personal property, sales, use, transfer, license, payroll, social security, medicare, franchise, gains, built-in gains, unemployment insurance, escheat, workers’ compensation, employer health tax or other taxes, imposed by any Governmental Authority (including withholding on amounts paid to or by any Person), together with any interest, penalty, addition to tax or additional amount imposed by any Governmental Authority (a “Taxing Authority”) responsible for the imposition of any such tax (domestic or foreign), and any liability for any of the foregoing as transferee, (ii) liability for the payment of any amount of the type described in clause (i) as a result of being or having been before the Effective Time a member of an affiliated, consolidated, combined or unitary group or similar arrangement required or permitted under applicable Law.

“Tax Return” means any report, return, document, declaration or other information or filing required to be supplied to any Taxing Authority with respect to Taxes, including information returns, any documents with respect to or accompanying payments of estimated Taxes, or with respect to or accompanying requests for the extension of time in which to file any such report, return, document, declaration or other information.

Section 4.15.  Labor and Employment.  (a) The Company and its Subsidiaries have complied with all Laws relating to labor and employment, including those relating to wages, hours, collective bargaining, unemployment compensation, worker’s compensation, equal employment opportunity, age and disability discrimination, immigration control, employee classification, information privacy and security, payment and withholding of taxes, and continuation coverage with respect to group health plans, except for such matters as would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

(b) Except as set forth in Section 4.15(b) of the Company Disclosure Schedule, neither the Company nor any of its Subsidiaries is a party to or subject to, or is currently negotiating in connection with entering into, any collective bargaining agreement or other labor agreement with any union or labor organization, and to the knowledge of the Company there has not been any activity or proceeding of any labor organization or employee group to organize any such employees. Furthermore, (i) there are no unfair labor practice charges or complaints against the Company or any of its Subsidiaries pending before the National Labor Relations Board; (ii) there are no labor strikes, slowdowns or stoppages actually pending or to the knowledge of the Company threatened against or affecting the Company or any of its Subsidiaries; (iii) there are no representation claims or petitions pending before the National Labor Relations Board or any foreign equivalent; and (iv) there are no grievance or pending arbitration proceedings against the Company or any of its Subsidiaries that arose out of or under any collection bargaining agreement, in each case, except for such matters as would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

Section 4.16.  Employee Benefit Plans.  (a) Section 4.16(a) of the Company Disclosure Schedule contains a correct and complete list identifying each material “employee benefit plan,” as defined in Section 3(3) of ERISA, each material employment, severance or similar contract, plan, arrangement or policy and each other material plan or arrangement (written or oral) providing for compensation, bonuses, profit-

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sharing, stock option or other stock related rights or other forms of incentive or deferred compensation, vacation benefits, insurance (including any self-insured arrangements), health or medical benefits, employee assistance program, disability or sick leave benefits, workers’ compensation, supplemental unemployment benefits, severance benefits and post-employment or retirement benefits (including compensation, pension, health, medical or life insurance benefits) which is maintained, administered or contributed to by the Company or any Affiliate and covers any employee or former employee of the Company or any of its Subsidiaries, or with respect to which the Company or any of its Subsidiaries has any liability. Copies of such plans (and, if applicable,related trust or funding agreements or insurance policies) and all amendments thereto have been made available to Parent together with the most recent annual report (Form 5500 including, if applicable, Schedule B thereto) and tax return (Form 990) prepared in connection with any such plan or trust. Such plans are referred to collectively herein as the “Employee Plans.” Employee Plans that primarily cover any employee or former employee outside of the United States are referred to herein collectively as “International Plans” and are specifically identified in Section 4.16(a) of the Company Disclosure Schedule by an asterisk.

(b) Neither the Company nor any ERISA Affiliate nor any predecessor thereof sponsors, maintains or contributes to, or has in the six-year period preceding the date hereof sponsored, maintained or contributed to, any employee plan subject to Title IV of ERISA. The Company does not maintain or contribute to, or have liability in connection with, any Employee Plan that is a “defined-benefit” type or similar actuarial arrangement that primarily covers employees or former employees outside of the United States, other than any such arrangements that are mandated by local law.

(c) Neither the Company nor any ERISA Affiliate nor any predecessor thereof contributes to, or has in the six-year period preceding the date hereof contributed to, any multiemployer plan, as defined in Section 3(37) of ERISA (a “Multiemployer Plan”).

(d) Except for matters that would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect, each Employee Plan has been maintained in compliance with its terms and with the requirements prescribed by any and all statutes, orders, rules and regulations, including ERISA and the Code, which are applicable to such Employee Plan. Each Employee Plan that is intended to be qualified under Section 401(a) of the Code has received a favorable determination letter, or has pending or has time remaining in which to file, an application for such determination from the Internal Revenue Service, and the Company is not aware of any reason why any such determination letter should be revoked or not be issued. The Company has made available to Parent copies of the most recent Internal Revenue Service determination letters with respect to each such Employee Plan. Except for matters that would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect, no events have occurred with respect to any Employee Plan that could result in payment or assessment by or against the Company of any excise taxes under Sections 4972, 4975, 4976, 4977, 4979, 4980B, 4980D, 4980E or 5000 of the Code.

(e) Except as set forth in Section 4.16(e) of the Company Disclosure Schedule, the consummation by the Company of the transactions contemplated by this Agreement will not (either alone or together with any other event) entitle any employee or independent contractor of the Company or any of its Subsidiaries to any severance, bonus, retirement, job security or similar benefit or enhance such benefit or accelerate the time of payment or vesting or trigger any payment or funding (through a grantor trust or otherwise) of compensation or benefits under, or increase the amount payable or trigger any other material obligation pursuant to, any Employee Plan. There is no contract, plan or arrangement (written or otherwise) covering any employee or former employee of the Company or any of its Subsidiaries that, individually or collectively, would entitle any employee or former employee to any severance or other payment solely as a result of the transactions contemplated hereby, or could give rise to the payment of any amount that would not be deductible pursuant to the terms of Section 280G of the Code.

(f) Neither the Company nor any of its Subsidiaries has any liability in respect of post-retirement health, medical or life insurance benefits for retired, former or current employees of the Company or its Subsidiaries except (i) as required to avoid excise tax under Section 4980B of the Code or (ii) for benefits provided during any severance period pursuant to a written employment or separation plan or agreement and that in the aggregate do not constitute a material liability of the Company.

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(g) Except as set forth in Section 4.16(g) of the Company Disclosure Schedule or as required or deemed advisable by applicable Law, there has been no amendment to, written interpretation or announcement (whether or not written) by the Company or any of its Affiliates relating to, or change in employee participation or coverage under, an Employee Plan which would increase the expense of maintaining such Employee Plan above the level of the expense incurred in respect thereof for the fiscal year ended December 31, 2006 by an amount that would reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

(h) For purposes of this Agreement:

“ERISA” means the Employee Retirement Income Security Act of 1974.

“ERISA Affiliate” of any entity means any other entity that, together with such entity, would be treated as a single employer under Section 414 of the Code.

Section 4.17.  Environmental Matters.  (a) Except as would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect:

(i) no notice, notification, demand, request for information, citation, summons or order has been received, no complaint has been filed, no penalty has been assessed, and no investigation, action, claim, suit, proceeding or review is pending or, to the knowledge of the Company, is threatened by any Governmental Authority or other Person relating to the Company or any of its Subsidiaries and relating to or arising out of any alleged violation of or liability under any Environmental Law or Environmental Permit, or seeking costs, damages, fines, penalties or injunctive relief relating to any Hazardous Substance;

(ii) the Company and its Subsidiaries have all required Environmental Permits and are and have been in compliance with all Environmental Laws and Environmental Permits; and

(iii) there are no liabilities or obligations of the Company or any of its Subsidiaries of any kind whatsoever, whether accrued, contingent, absolute, determined, determinable or otherwise, arising under or relating to any Environmental Law, Environmental Permit or any Hazardous Substance.

(b) There has been no material environmental site investigation, environmental report or other written environmental analysis that is in the possession or control of the Company or any of its Subsidiaries in relation to the current or former business of, or any property or facility now or previously owned, leased or operated by, the Company or any of its Subsidiaries that has not been provided to Parent at least five Business Days prior to the date hereof.

(c) Neither the Company nor any of its Subsidiaries owns, leases or operates or has owned, leased or operated any real property, or conducts or has conducted any operations, in New Jersey or Connecticut. The consummation of the transactions contemplated hereby require no filings to be made or actions to be taken pursuant to any Environmental Law or Environmental Permit.

(d) For purposes of this Section 4.17, the terms “Company” and “Subsidiaries” shall include any entity that is, in whole or in part, a predecessor of the Company or any of its Subsidiaries, and for purposes of this Agreement

“Environmental Laws” means any Law, permit requirement, judgment, injunction, order or decree of, or agreement with, any Governmental Authority or other third party relating to the protection of the environment, employee health and safety or pollutants, contaminants or otherwise hazardous substances, wastes or materials, including exposure thereto.

“Environmental Permits” means all permits, licenses, franchises, certificates, approvals and other similar authorizations of or from Governmental Authorities relating to or required by Environmental Laws and affecting, or relating to, the business of the Company or any of its Subsidiaries as currently conducted.

“Hazardous Substance” means any pollutant, contaminant or chemical or any toxic, radioactive, ignitable, corrosive, reactive or otherwise hazardous substance, waste (including infectious and medical waste) or

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material, or any substance, waste or material having any constituent elements displaying any of the foregoing characteristics, listed, defined or regulated under any Environmental Law.

Section 4.18.   Material Contracts.  Except as set forth in the Filed SEC Documents, neither the Company nor any of its Subsidiaries is a party to or bound by any “material contract” (as such term is defined in item 601(b)(10) of Regulation S-K of the SEC) (all such contracts, the “Material Contracts”).

True and complete copies of all such Material Contracts and all amendments to or waivers thereunder have been made available by the Company to Parent. Except for breaches, violations or defaults which would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect, (a) each of the Material Contracts is valid and in full force and effect and (b) neither the Company nor any of its Subsidiaries, nor to the Company’s knowledge any other party to a Material Contract, has violated any provision of, or taken or failed to take any act which, with or without notice or lapse of time or both, would constitute a default under the provisions of such Material Contract, and neither the Company nor any of its Subsidiaries has received notice that it has breached, violated or defaulted under any Material Contract. Other than exclusive distributor arrangements entered into in the ordinary course of business consistent with past practice, and except as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect or a material adverse effect on the operations of Parent and its Subsidiaries, neither the Company nor any of its Subsidiaries is party to any agreement or arrangement that limits or otherwise restricts the ability of the Company or any of its Subsidiaries (or, after the consummation of the Offer or the Merger, Parent, the Company or any of their respective Subsidiaries or any successor thereto) to engage or compete in any line of business, in any location or with any Person.

Section 4.19.   Intellectual Property.  (a) For purposes of this Agreement,

“Intellectual Property” means all U.S. and foreign (i) patents and all proprietary rights associated therewith, (ii) trademarks, service marks, trade names, trade dress, domain names, brand names, certification marks, corporate names and other indications of origin, together with all goodwill related to the foregoing, (iii) copyrights and designs and all rights associated therewith and the underlying works of authorship, (iv) all inventions, trade secrets, processes, formulae, methods, schematics, drawings, blue prints, technology, know-how, software, discoveries, ideas and improvements, (v) all registrations of any of the foregoing and all applications therefor and (vi) other proprietary or confidential information and materials.

“Company Intellectual Property” means all Intellectual Property that is owned or exclusively licensed by the Company or any of its Subsidiaries, and includes without limitation all of the Company Registered Intellectual Property as defined below.

(b) Except as set forth in Section 4.19(b) of the Company Disclosure Schedule or as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect: (i) the Company and its Subsidiaries own, or otherwise possess legally enforceable rights to use all Intellectual Property necessary to conduct the business of the Company and its Subsidiaries as currently conducted (the “Necessary Intellectual Property”), (ii) the execution and delivery of this Agreement by the Company and the consummation of the transactions contemplated by this Agreement will not alter, encumber, impair or extinguish any Necessary Intellectual Property or any of the Company and its Subsidiaries’ material rights therein, other than with respect to off the shelf software that is commercially available on nondiscriminatory pricing terms (“Off-the-Shelf Software”), (iii) there is no claim, action, suit, investigation or proceeding pending or, to the knowledge of the Company, threatened against the Company or any of its Subsidiaries (A) challenging or seeking to deny or restrict the rights of the Company or any of its Subsidiaries in any Necessary Intellectual Property, or (B) alleging that any services provided, processes used or products manufactured or sold by or on behalf of the Company or any of its Subsidiaries infringe, violate or otherwise misappropriate any Intellectual Property right of any third party, or that the Company or any of its Subsidiaries have done so within the past two years, (iv) there are no restrictions on the disclosure, use, license or transfer by the Company of the Company Intellectual Property or the Necessary Intellectual Property and (v) no third party has been granted any current or contingent license or immunity to sell, license or otherwise distribute products or services utilizing the Company Intellectual Property.

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(c) Section 4.19(c) of the Company Disclosure Schedule lists all material (i) patents and patent applications, (ii) trademark, trade name and service mark registrations (including Internet domain name registrations) and applications therefor and (iii) copyright registrations and applications included in the Company Intellectual Property (collectively, “Company Registered Intellectual Property”). All applications for Company Registered Intellectual Property are without challenge, all registrations of Company Registered Intellectual Property are in force, and all annuity, maintenance, renewal and other fees that have become due relating to any Company Registered Intellectual Property have been properly paid in accordance with all applicable requirements. Except as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, the Company and its Subsidiaries are the sole and exclusive owners of the Company Intellectual Property (excluding Intellectual Property that is licensed exclusively by the Company or any of its Subsidiaries), free and clean of any Liens.

(d) Except as set forth in Section 4.19(d) of the Company Disclosure Schedule or as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, none of the Company Intellectual Property has been adjudged (by consent or otherwise) invalid, unenforceable, not owned solely by the Company, or not infringed; and no claims with respect to Company Intellectual Property are pending, or to the knowledge of the Company, threatened by any Person challenging the ownership, validity, enforceability or effectiveness of any of the Company Intellectual Property.

(e) The Company and its Subsidiaries have used reasonable commercial efforts to maintain the confidentiality of all material Company Intellectual Property the value of which is contingent upon maintaining the confidentiality thereof. Except as set forth in Section 4.19(e) of the Company Disclosure Schedule, to the knowledge of the Company, no such Intellectual Property has been disclosed other than to employees, representatives and agents all of whom are bound by written confidentiality agreements. Except as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, the Company and its Subsidiaries have appropriate procedures in place designed to provide that all Intellectual Property conceived by their employees as a result of performing their duties for the Company and its Subsidiaries and third parties performing research and development for them have been assigned or are required to be assigned to the Company or any of its Subsidiaries. To the knowledge of the Company, the Company and its Subsidiaries are in material compliance with all confidentiality agreements and other protective agreements to which they are a party that protect the Intellectual Property of third parties.

(f) To the knowledge of the Company, no party other than the Company or its Subsidiaries possesses any current or contingent rights to any material source code that is part of the Company Intellectual Property.

(g) To the knowledge of the Company, no third party is infringing any Company Intellectual Property in a manner that materially impairs the enforceability of such Company Intellectual Property.

Section 4.20.  Finders’ Fees.  Except for (a) Merrill Lynch, Pierce, Fenner & Smith Incorporated and Goldman, Sachs & Co. (the “Company Financial Advisors”) and (b) P&M Corporate Finance, LLC, there is no investment banker, broker, finder or other intermediary that has been retained by or is authorized to act on behalf of the Company or any of its Subsidiaries who is entitled to any fee or commission from the Company or any of its Affiliates in connection with the transactions contemplated by this Agreement. The aggregate amount of all such fees or commissions does not exceed the amount set forth in Section 4.20 of the Company Disclosure Schedule.

Section 4.21.  Opinion of Financial Advisors.  The Board of Directors has received opinions of the Company Financial Advisors to the effect that, as of the date of such opinions, the consideration to be paid in the Offer and the Merger is fair, from a financial point of view, to the holders of the Shares.

Section 4.22.  Anti-takeover Statutes and Rights Agreement.  (a) Assuming that neither Parent nor any of its Affiliates is an “interested stockholder” (as defined in Section 203 of Delaware Law) as of immediately prior to the execution and delivery of this Agreement, the Company has taken all action necessary to exempt the Offer, the Merger, this Agreement and the transactions contemplated hereby from the restrictions on business combinations of Section 203 of Delaware Law and, to the extent permissible under applicable Law, all provisions of Sections 10-2721 to 10-2727 and Sections 10-2741 to 10-2743 of the Arizona Revised

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Statutes that apply or purport to apply to the Offer, the Merger, this Agreement and the transactions contemplated hereby. To the knowledge of the Company, except for Section 203 of Delaware Law and such provisions of the Arizona Revised Statutes, no other “control share acquisition,” “fair price,” “moratorium” or other anti-takeover laws enacted under U.S. state or federal laws apply to this Agreement or any of the transactions contemplated hereby.

(b) The Company has taken all action necessary to render the rights (the “Company Rights”) issued pursuant to the Rights Agreement dated as of May 6, 1998, between the Company and Wells Fargo Bank, N.A. (as successor to Norwest Bank Minnesota, N.A.) (the “Rights Agreement”) inapplicable to the Offer, the Merger, this Agreement and the transactions contemplated hereby.

ARTICLE 5

Representations and Warranties of Parent

Parent represents and warrants to the Company that:

Section 5.01.  Corporate Existence and Power.  Each of Parent and Merger Subsidiary is duly incorporated, validly existing and in good standing under the laws of its jurisdiction of incorporation (to the extent such jurisdiction recognizes the concept of good standing) and has all corporate powers and all governmental licenses, authorizations, permits, consents and approvals required to carry on its business in substantially the same manner as now conducted, except for those licenses, authorizations, permits, consents and approvals the absence of which would not reasonably be expected to have, individually or in the aggregate, a Parent Material Adverse Effect.

Section 5.02.  Corporate Authorization.  The execution, delivery and performance by Parent and Merger Subsidiary of this Agreement and the consummation by Parent and Merger Subsidiary of the transactions contemplated hereby are within the corporate powers of Parent and Merger Subsidiary and have been duly authorized by all necessary corporate action. This Agreement constitutes a valid and binding agreement of each of Parent and Merger Subsidiary.

Section 5.03.  Governmental Authorization.  The execution, delivery and performance by Parent and Merger Subsidiary of this Agreement and the consummation by Parent and Merger Subsidiary of the transactions contemplated hereby require no action by or in respect of, or filing with, any Governmental Authority, other than (a) the filing of a certificate of merger (or certificate of ownership and merger) with respect to the Merger with the Delaware Secretary of State, (b) compliance with any applicable Antitrust Laws, (c) compliance with any applicable requirements of the 1934 Act or any other U.S. state or federal securities laws and (d) any actions or filings the absence of which would not reasonably be expected to have, individually or in the aggregate, a Parent Material Adverse Effect.

Section 5.04.  Non-contravention.  The execution, delivery and performance by Parent and Merger Subsidiary of this Agreement and the consummation by Parent and Merger Subsidiary of the transactions contemplated hereby do not and will not (a) contravene, conflict with, or result in any violation or breach of any provision of the certificate of incorporation, bylaws or other organizational documents of Parent or Merger Subsidiary, (b) assuming compliance with the matters referred to in Section 5.03, contravene, conflict with, or result in any violation or breach of any provision of applicable Law or any judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction, (c) require any consent or other action by any Person under, constitute a default, or an event that, with or without notice or lapse of time or both, could become a default, under, or cause or permit the termination, cancellation, acceleration or other change of any right or obligation or the loss of any benefit to which Parent or Merger Subsidiary is entitled under any provision of any agreement or other instrument binding upon Parent or Merger Subsidiary, or any license, franchise, permit, certificate, approval or other similar authorization affecting, or relating in any way to, the assets or business of Parent or Merger Subsidiary or (d) result in the creation or imposition of any Lien on any asset of Parent or Merger Subsidiary except, in the case of clauses (b) through (d), for such matters as would not reasonably be expected to have, individually or in the aggregate, a Parent Material Adverse Effect.

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Section 5.05.  Disclosure Documents.  (a) The information with respect to Parent and any of its Affiliates that Parent furnishes to the Company in writing specifically for inclusion or incorporation by reference in any Company Disclosure Document will not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements made therein, in the light of the circumstances under which they were made, not misleading (i) in the case of the proxy or information statement of the Company (the “Company Proxy Statement”), if any, to be filed with the SEC in connection with the Merger, as supplemented or amended, if applicable, at the time such Company Proxy Statement or any amendment or supplement thereto is first mailed to stockholders of the Company and at the time such stockholders vote on adoption of this Agreement, and (ii) in the case of any Company Disclosure Document other than the Company Proxy Statement, at the time of the filing of such Company Disclosure Document or any supplement or amendment thereto and at the time of any distribution or dissemination thereof.

(b) The Schedule TO, when amended and filed in accordance with this Agreement, and the Offer Documents, when distributed or disseminated in accordance with this Agreement, will comply as to form in all material respects with the applicable requirements of the 1934 Act and, at the time of such filing, at the time of such distribution or dissemination and at the time of consummation of the Offer, will not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements made therein, in the light of the circumstances under which they were made, not misleading; provided that this representation and warranty will not apply to statements or omissions in the Schedule TO and the Offer Documents based upon information furnished to Parent or Merger Subsidiary in writing by the Company specifically for inclusion or incorporation by reference therein.

Section 5.06.  Finders’ Fees.  Except for Citigroup Global Markets Inc. and Greenhill & Co., LLC, whose fees and expenses will be paid by Parent, there is no investment banker, broker, finder or other intermediary that has been retained by or is authorized to act on behalf of Parent who is entitled to any fee or commission from Parent or any of its Affiliates in connection with the transactions contemplated by this Agreement.

Section 5.07.  Financing.  Merger Subsidiary has sufficient cash, available lines of credit or other sources of immediately available funds (or such funds will be made available to Merger Subsidiary by Parent or an Affiliate of Parent at each of the Acceptance Date and Effective Time) to enable it to purchase all of the Shares outstanding on a fully-diluted basis and to pay all related fees and expenses pursuant to the Offer and the Merger.

Section 5.08.  Operations of Merger Subsidiary.  Merger Subsidiary is an indirect, wholly owned Subsidiary of Parent that was formed solely for the purpose of engaging in the Offer, the Merger and the transactions contemplated by this Agreement, and Merger Subsidiary has engaged in no business activity, has conducted no operations and has incurred no liability, other than in connection with the Offer, the Merger and the transactions contemplated by this Agreement.

ARTICLE 6

Covenants of the Company

The Company agrees that:

Section 6.01.  Conduct of the Company.  From the date hereof until the earlier of the Acceptance Date or termination of this Agreement in accordance with its terms, except as (i) required by applicable Laws, (ii) contemplated by this Agreement, or (iii) set forth in Section 6.01 of the Company Disclosure Schedule, the Company shall, and shall cause each of its Subsidiaries to, use their respective reasonable best efforts to conduct their businesses in all material respects in the ordinary course consistent with past practices and use their respective reasonable best efforts to (A) preserve intact their present business organizations, (B) keep available the services of their officers, employees and consultants, and (C) maintain relationships with their customers, suppliers and others having significant business relationships with them. Without limiting the generality of the foregoing, except as (x) required by applicable Law, (y) contemplated by this Agreement, or (z) set forth in Section 6.01 of the Company Disclosure Schedule, without Parent’s prior written consent

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(which consent shall not be unreasonably withheld or delayed), the Company shall not, nor shall it permit any of its Subsidiaries to:

(a) amend its articles of incorporation, bylaws or other similar organizational documents (whether by merger, consolidation or otherwise);

(b) split, combine or reclassify any shares of its capital stock or declare, set aside or pay any dividend or other distribution (whether in cash, stock or property or any combination thereof) in respect of its capital stock except for dividends payable by any wholly-owned Subsidiaries of the Company, or redeem, repurchase or otherwise acquire or offer to redeem, repurchase or otherwise acquire any Company Securities or any Company Subsidiary Securities;

(c) (i) issue, sell or otherwise deliver, or authorize the issuance, sale or other delivery of, any Company Securities or Company Subsidiary Securities, other than (A) the issuance of Shares upon the exercise of Company Stock Options that were outstanding on January 20, 2008 in accordance with the terms of those options on such date and (B) the issuance by any direct or indirect wholly-owned Subsidiary of the Company of Company Subsidiary Securities to the Company or to another direct or indirect wholly owned Subsidiary of the Company, or the purchase of Shares pursuant to the Company ESPP in accordance with its terms as in effect on the date hereof or (ii) amend any term of any Company Security or any Company Subsidiary Security (whether by merger, consolidation or otherwise);

(d) incur any capital expenditures or any obligations or liabilities in respect thereof, except for (i) those contemplated by the capital expenditure budget attached to Section 6.01 of the Company Disclosure Schedule, (ii) any unbudgeted capital expenditures in an amount not to exceed $2 million individually or $10 million in the aggregate incurred in the ordinary course of business consistent with past practices or in connection with the Company’s current build out at its Tucson, Arizona campus and (iii) capital expenditures incurred in the ordinary course of business consistent with past practices in connection with placement of field assets at customer sites;

(e) make any loans, advances or capital contributions to, or investments in, any other Person except for loans, advances and capital contributions in the ordinary course of business consistent with past practices;

(f) acquire any material assets or property other than capital expenditures permitted pursuant to Section 6.01(d) and purchases of inventory and supplies in the ordinary course of business consistent with past practices;

(g) except as permitted pursuant to Section 6.01(h), sell, lease, license or otherwise transfer any material assets or property other than sales of products of the Company and its Subsidiaries or third parties for whom the Company and its Subsidiaries act as resellers in the ordinary course of business consistent with past practices;

(h) sell, assign, license or otherwise transfer any Necessary Intellectual Property or Company Intellectual Property (or any rights therein) or acquire any material Intellectual Property other than in the ordinary course of business consistent with past practices;

(i) incur, guaranty or otherwise become liable for any indebtedness for borrowed money other than in the ordinary course of business consistent with past practices, other than indebtedness existing solely between the Company and its wholly owned Subsidiaries or between such wholly owned Subsidiaries;

(j) except as permitted pursuant to Sections 6.01(g) or 6.01(h), create or incur any material Lien on any material assets or property;

(k) enter into any agreement or arrangement that limits or otherwise restricts in any material respect the Company or any of its Subsidiaries or any successor thereto or that could, after the consummation of the Offer or the Merger, limit or otherwise restrict in any material respect Parent, the Company or any of their respective Affiliates or any successor thereto, from engaging or competing in any line of business, in any location or with any Person;

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(l) amend, modify or waive in any material respect or terminate any Material Contract or enter into any agreement that would constitute a Material Contract if entered into as of the date hereof except in the ordinary course of business consistent with past practices;

(m) except as required by the terms of an applicable plan or agreement in effect on the date hereof or as required or deemed advisable pursuant to applicable Law, (i) increase compensation, bonuses or other benefits payable to any director or executive officer or, except in the ordinary course of business consistent with past practices, any other employee of the Company or any of its Subsidiaries or (ii) enter into, adopt or amend in any material respect any employment, change of control, severance, compensation, bonus, profit-sharing, stock option or other stock related rights or other forms of incentive or deferred compensation, retirement benefits or other benefit agreement, plan, arrangement or policy applicable to any director or executive officer or, except in the ordinary course of business consistent with past practices, any other employee of the Company or any of its Subsidiaries;

(n) (i) settle, or propose to settle, any litigation, investigation, arbitration, proceeding or claim that is material to the Company and its Subsidiaries taken as a whole or that relates to the transactions contemplated hereby, or (ii) waive, release or assign any material rights or claims;

(o) materially change the Company’s methods of accounting, except as required by concurrent changes in GAAP or by applicable Law, as agreed to by its independent public accountants;

(p) except as may be required by Law, make or change any material Tax election, change any annual Tax accounting period, adopt or change any method of Tax accounting, materially amend any Tax Returns or file claims for material Tax refunds, enter into any material closing agreement, settle any material Tax claim, audit or assessment, or surrender any right to claim a material Tax refund, offset or other reduction in Tax liability; or

(q) resolve, commit or agree to do any of the foregoing.

Section 6.02.  Stockholder Meeting; Proxy Material.  If required by Delaware Law to consummate the Merger, the Company shall cause a meeting of its stockholders (the “Company Stockholder Meeting”) to be duly called and held as soon as reasonably practicable after the Acceptance Date for the purpose of voting on the adoption of this Agreement; provided that the Company shall not be required to mail the Company Proxy Statement or any other proxy materials relating to the vote of the Company’s stockholders with respect to the adoption of this Agreement prior to the Acceptance Date. Subject to Section 6.04(b), the Company Board Recommendation shall be included in the Company Proxy Statement. In connection with such meeting, the Company shall, following the Acceptance Date, (a) promptly prepare and file with the SEC, use its reasonable best efforts to have cleared by the SEC and thereafter mail to its stockholders as promptly as practicable the Company Proxy Statement and all other proxy materials required by Law for such meeting, (b) use its reasonable best efforts to obtain the Company Stockholder Approval and (c) otherwise comply with all legal requirements applicable to such meeting.

Section 6.03.  Access to Information.  From the date hereof until the Effective Time, the Company shall (a) provide Parent, its counsel, financial advisors, auditors and other authorized representatives reasonable access to the properties, offices and books and records of the Company and its Subsidiaries and such financial and operating data and other information as such Persons may reasonably request and (b) instruct the employees, counsel, financial advisors, auditors and other authorized representatives of the Company and its Subsidiaries to cooperate with Parent in its investigation of the Company and its Subsidiaries. Any investigation pursuant to this Section 6.03 shall comply with applicable Law and be conducted during business hours and in such manner so as not to interfere unreasonably with the conduct of the business of the Company and its Subsidiaries. No information or knowledge obtained by Parent in any investigation pursuant to this Section 6.03 shall affect or be deemed to modify any representation or warranty made by the Company hereunder. Nothing in this Section 6.03 shall require the Company (i) to permit any inspection, or to disclose any information, that in the reasonable judgment of the Company would result in the disclosure of any trade secrets of third Persons or violate any of the Company’s obligations with respect to confidentiality, (ii) to disclose any privileged information of the Company or any of its Subsidiaries, (iii) to disclose any information

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the disclosure of which could, in the reasonable judgment of the Company, cause significant competitive harm to the Company if the transactions contemplated hereby are not consummated or (iv) to permit invasive testing of any of the Company’s or its Subsidiaries’ real property. In no event shall the Company be required to supply pursuant to this Section 6.03 to Parent, or Parent’s representatives, any information relating to indications of interest from, or discussions with, any other potential acquirers of the Company, with respect to which Section 6.04 shall apply. All requests for access to the offices or books and records of the Company or its Subsidiaries shall be made to such representatives of the Company as the Company shall designate, who shall be solely responsible for coordinating all such requests and all access permitted hereunder. All information disclosed by the Company to Parent and its representatives pursuant hereto shall be subject to the terms of the Confidentiality Agreement (the “Confidentiality Agreement”) dated November 13, 2007 between the Company and Roche Holding Ltd, a joint stock company organized under the laws of Switzerland (“Holding”).

Section 6.04.  No Solicitation; Change of Recommendation.  (a) Neither the Company nor any of its Subsidiaries shall, nor shall the Company or any of its Subsidiaries authorize or permit any of its officers, directors or employees to (and the Company and its Subsidiaries shall use their respective reasonable best efforts to cause their respective counsel, financial advisors, auditors and other agents and representatives not to) (such counsel, financial advisors, auditors and other agents and representatives, together with the officers, directors and employees of the Company and its Subsidiaries, collectively referred to herein as the “Company Representatives”), directly or indirectly:

(i) solicit, initiate or knowingly take any action to encourage or facilitate the making of an Acquisition Proposal,

(ii) participate in any discussions or negotiations with or furnish any information with respect to the Company or any of its Subsidiaries to any third party in connection with an Acquisition Proposal,

(iii) take any action to render the Company Rights or Section 203 of Delaware Law inapplicable to any transaction included in the definition of Acquisition Proposal or grant any waiver or release under any standstill or similar agreement with respect to any class of equity securities of the Company or any of its Subsidiaries, or

(iv) approve or enter into any agreement (including an agreement in principle, letter of intent, term sheet or other similar instrument) with respect to an Acquisition Proposal.

Notwithstanding the foregoing, if at any time prior to the Acceptance Date, the Company receives a bona fide written Acquisition Proposal that was not solicited on or after the date of this Agreement, (1) the Company and Company Representatives may contact the third party or parties making such Acquisition Proposal solely for the purpose of clarifying the terms and conditions thereof and (2) if the Board of Directors determines in good faith (after considering the advice of its outside legal and financial advisors) that such Acquisition Proposal is or could be reasonably expected to result in a Superior Proposal, the Company may:

(x) subject to entering into a confidentiality agreement with terms no less favorable in the aggregate in any material respect to the Company than those contained in the Confidentiality Agreement, furnish information (including non-public information) with respect to the Company or any of its Subsidiaries to the third party or parties that made such Acquisition Proposal and participate in discussions or negotiations with respect to such Acquisition Proposal; provided that (i) the Company shall notify Parent promptly (but in no event later than 24 hours) after receipt of any Acquisition Proposal or any request for information with respect to the Company or any of its Subsidiaries by a third party or parties that has made or is considering making an Acquisition Proposal or any indication that a third party is considering making an Acquisition Proposal (such notice to identify the third party and contain the material terms and conditions of any such proposal, request or indication); (ii) the Company shall keep Parent informed, on a prompt basis, of the status of, and any material changes in any such proposal, request or indication; and (iii) the Company shall

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promptly provide to Parent any material information furnished to the third party that has not previously been provided by Parent; and

(y) approve and enter into a definitive agreement with respect to a Superior Proposal and take any actions listed in Section 6.04(a)(iii) or 6.04(a)(iv), as applicable; provided that (i) the Company shall have complied in all material respects with the provisions of this Section 6.04; (ii) the Company shall have notified Parent in writing that the Board of Directors has determined that the Acquisition Proposal is a Superior Proposal and intends, subject to clause (iii) below, to enter into such a definitive agreement with respect to the Superior Proposal and to terminate this Agreement and attaching the most current version of such agreement (or a summary containing all the material terms and conditions thereof and identifying the third party that has made such proposal); (iii) Parent does not make, within three Business Days after receipt of such written notice, an offer that the Board of Directors shall have concluded in good faith (after considering the advice of its outside legal and financial advisors) causes such Acquisition Proposal to cease to be a Superior Proposal (it being understood that the Company shall not enter into an agreement with respect to the Superior Proposal during such three Business Day period) and (iv) the Company shall, concurrently with entering into such definitive agreement, terminate this Agreement and pay the Termination Fee contemplated by Section 11.04(b).

(b) The Board of Directors shall not fail to make, withdraw or modify in a manner adverse to Parent the Company Board Recommendation or publicly recommend or announce its intention to enter into an agreement (including an agreement in principle, letter of intent, term sheet or other similar instrument) with respect to any Acquisition Proposal or otherwise take any action or make any statement inconsistent with the Company Board Recommendation (collectively, an “Adverse Recommendation Change”). Notwithstanding the foregoing, at any time prior to the Company Stockholder Approval the Board of Directors may make an Adverse Recommendation Change if the Board of Directors determines in good faith (after considering the advice of its outside legal and financial advisors) that the failure to take such action would be inconsistent with its fiduciary duties under Delaware Law.

(c) It is understood and agreed that any “stop, look and listen” communication pursuant to Rule 14d-9(f) under the 1934 Act or other factually accurate public statement by the Company that, in each case, merely describes the Company’s receipt of an Acquisition Proposal and the operation of this Agreement with respect thereto and reaffirms the Company Board Recommendation shall not be deemed to be an Adverse Recommendation Change. Nothing in this Section 6.04 or elsewhere in this Agreement shall prevent the Board of Directors from disclosing any information required to be disclosed under applicable Law or from complying with Rule 14d-9 or Rule 14e-2(a) promulgated under the 1934 Act with respect to an Acquisition Proposal (or any similar communication to holders of Shares in connection with the making or amendment of a tender offer or exchange offer). In addition, nothing in this Section 6.04 or this Agreement shall prohibit the Company from taking any action that any court of competent jurisdiction orders the Company to take.

(d) The Company and its Subsidiaries shall, and shall cause their officers, directors and employees (and the Company and its Subsidiaries shall use their respective reasonable best efforts to cause their respective counsel, financial advisors, auditors, consultants and other agents and representatives) to cease immediately and cause to be terminated any and all existing activities, discussions or negotiations, if any, with any third party conducted prior to the date hereof with respect to any Acquisition Proposal. The Company shall promptly request that each third party, if any, that has executed a confidentiality agreement in connection with a possible Acquisition Proposal return or destroy all confidential information heretofore furnished to such Person by or on behalf of the Company or any of its Subsidiaries (and all analyses and other materials prepared by or on behalf of such Person that contains, reflects or analyzes that information).

(e) For purposes of this Agreement:

“Acquisition Proposal” means any inquiry, proposal or offer from any Person or Persons (other than Parent and its Affiliates) relating to any (i) acquisition of assets of the Company and its Subsidiaries (including securities of Subsidiaries) representing 20% or more of the Company’s consolidated assets or revenues, (ii) acquisition of 20% or more of the outstanding Shares, (iii) tender offer or exchange offer that if

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consummated would result in any Person beneficially owning 20% or more of the outstanding Shares or (iv) merger, consolidation, share exchange, business combination, recapitalization, reorganization, liquidation, dissolution or similar transaction involving the Company, in each case, other than the transactions contemplated by this Agreement.

“Superior Proposal” means any Acquisition Proposal (with all percentages in the definition of “Acquisition Proposal” changed to 50%) on terms that the Board of Directors determines in good faith (after considering the advice of its outside legal and financial advisors and taking into account all the terms and conditions of the Acquisition Proposal) is reasonably likely to be capable of consummation and is more favorable to the Company’s stockholders than the Offer and the Merger (after giving effect to any subsequent offer made by Parent in response to such Superior Proposal).

ARTICLE 7

Covenants of Parent

Parent agrees that:

Section 7.01.  Obligations of Merger Subsidiary.  Parent shall take all action necessary (a) to cause Merger Subsidiary to perform its obligations under this Agreement and to consummate the Offer and the Merger on the terms and conditions set forth in this Agreement and (b) to ensure that, prior to the Effective Time, Merger Subsidiary shall not conduct any business or make any investments other than as specifically contemplated by this Agreement.

Section 7.02.  Voting of Shares.  Parent shall vote (or cause to be voted) all Shares beneficially owned by it or any of its Affiliates in favor of adoption of this Agreement at the Company Stockholder Meeting.

Section 7.03.  Director and Officer Liability.  (a) Parent shall cause the Surviving Corporation to do the following (and shall itself do the following as if it were the Surviving Corporation):

(i) for six years after the Effective Time, indemnify and hold harmless the current and former officers, directors, employees and employee benefit plan fiduciaries of the Company or any of its Subsidiaries (each, an “Indemnified Person”) in respect of acts, omissions or events occurring at or prior to the Effective Time to the fullest extent (A) provided in the certificate of incorporation or bylaws of the Company or the organizational documents of any Subsidiary of the Company, as applicable, or (B) permitted by applicable Law, in each case as in effect on the date of this Agreement;

(ii) for six years after the Effective Time, unless otherwise required by applicable Law, cause the Surviving Corporation’s and each of its Subsidiaries’ certificate of incorporation and bylaws or equivalent organizational documents (or any such documents of any successor to the business of the Surviving Corporation or any of its Subsidiaries) to contain provisions regarding limitations on personal liability of directors and indemnification of, and advancement of expenses to, Indemnified Persons in respect of acts, omissions or events occurring at or prior to the Effective Time that are no less advantageous to the intended beneficiaries than the corresponding provisions in the Company’s and its Subsidiaries’ certificate of incorporation and bylaws or equivalent organizational documents, in each case, as in effect on the date of this Agreement; provided that if any claim is asserted against any individual entitled to the protections of such provisions within such six-year period, such provisions shall not be modified until the final disposition of any such claims;

(iii) honor all obligations of the Company to each Indemnified Person (including rights relating to advancement of expenses and indemnification rights to which such Indemnified Persons are entitled because they are serving as a director, officer, agent or employee of another Person at the request of the Company or any of its Subsidiaries) in respect of acts, omissions or events occurring at or prior to the Effective Time to the fullest extent provided in any indemnification agreements to which the Company or any Subsidiary of the Company is a party as of the date hereof, in each case, as in effect on the date of this Agreement;

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(iv) either (A) continue to maintain in effect for six years after the Effective Time the Company’s directors’ and officers’ insurance policies and fiduciary liability insurance policies (collectively, the “D&O Insurance”) in place as of the date hereof with terms, conditions, retentions and limits of liability that are at least as favorable as those contained in the Company’s D&O Insurance policies in effect as of the date hereof or (B) purchase comparable D&O Insurance for such six-year period with terms, conditions, retentions and limits of liability that are at least as favorable as those contained in the Company’s D&O Insurance policies in effect as of the date hereof; provided that if the aggregate cost for such insurance coverage exceeds 300% of the current annual premium paid by the Company (which current annual premium amount is set forth in Section 7.03(a)(iv) of the Company Disclosure Schedule), the Surviving Corporation shall be obligated to obtain D&O Insurance with the best available coverage with respect to matters occurring at or prior to the Effective Time for an aggregate cost of 300% of the current annual premium; and

(v) if Parent or the Surviving Corporation or any of their respective successors or assigns (A) consolidates with or merges into any other Person and is not the continuing or surviving entity, (B) ceases to continue to exist for any reason, or (C) transfers or conveys all or substantially all of its properties and assets to any Person, then, and in each such case, to the extent necessary, ensure that the successors and assigns of Parent or the Surviving Corporation, as the case may be, shall assume the obligations set forth in this Section 7.03.

(b) Any determination required to be made with respect to whether the conduct of an Indemnified Person who is or was an officer or director of the Company complies with the standards set forth under applicable Law, the certificate of incorporation or bylaws of the Surviving Corporation or any indemnification agreement to which the Company is a party as of the date hereof, as the case may be, shall be made by independent legal counsel jointly selected by such Indemnified Person and Parent.

(c) Nothing in this Section 7.03 shall impair any rights of any Indemnified Person, and without limiting the generality of the foregoing, if any Indemnified Person who is or was an officer or director of the Company becomes involved in any actual or threatened action, suit, claim, proceeding or investigation covered by this Section 7.03 after the Effective Time, Parent shall, or shall cause the Surviving Corporation to, to the fullest extent permitted by applicable Law, promptly advance to such Indemnified Person such Indemnified Person’s legal or other expenses (including the cost of any investigation and preparation incurred in connection therewith), subject to the providing by such Indemnified Person of an undertaking to reimburse all amounts so advanced in the event of a non-appealable determination of a court of competent jurisdiction that such Indemnified Person is not entitled thereto.

(d) The rights of each Indemnified Person under this Section 7.03 shall be in addition to (and not in substitution for) any other rights such Indemnified Person may have under the certificate of incorporation or bylaws of the Company or equivalent organizational documents of any of its Subsidiaries, Delaware Law, any agreement with the Company or any of its Subsidiaries or otherwise and are intended for the benefit of and shall be enforceable by such Indemnified Person and such Indemnified Person’s heirs, executors or similar representatives. The rights under this Section 7.03 shall survive consummation of the Merger and shall not be amended in a manner that is adverse to the Indemnified Persons without the consent of the Indemnified Persons affected thereby.

Section 7.04.  Employee Matters.  (a) For a period of one year following the Effective Time, Parent shall provide to all employees of the Company or any of its Subsidiaries as of the Effective Time who continue employment with the Surviving Corporation or any of its Affiliates (“Continuing Employees”) with compensation and benefits that are in the aggregate substantially equivalent to compensation and benefits provided by the Company and its Subsidiaries as in effect immediately prior to the Acceptance Date.

(b) Parent shall ensure that, as of the Effective Time, each Continuing Employee receives full credit for all purposes (other than the accrual of benefits under a defined benefit pension plan) for service with the Company or any of its Subsidiaries (or predecessor employers to the extent the Company provides such past service credit) under the comparable employee benefit plans, programs and policies of Parent, the Surviving Corporation or any Affiliate of the Surviving Corporation, as applicable, in which such employee becomes a

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participant. With respect to each health or other welfare benefit plan maintained by Parent or the Surviving Corporation or any Affiliate of the Surviving Corporation, as applicable, for the benefit of any Continuing Employees, Parent shall (i) cause to be waived any waiting period requirements, insurability requirements and the application of any pre-existing condition limitations under such plan and (ii) cause each Continuing Employee to be given credit under such plan for all amounts paid by such Continuing Employee under any similar Company benefit plan for the plan year in which such participation commences for purposes of applying deductibles, co-payments and out-of-pocket maximums as though such amounts had been paid in accordance with the terms and conditions of the plans maintained by Parent, the Surviving Corporation or such Affiliate, as applicable, for such plan year. In addition, Parent shall implement, or cause its appropriate Affiliates to implement, the additional arrangements agreed upon by Parent and the Company.

(c) Parent shall cause the Surviving Corporation to assume and honor in accordance with their terms all written employment, change of control, severance, retention or termination agreements applicable to any employee of the Company or any of its Subsidiaries.

ARTICLE 8

Covenants of Parent and the Company

The parties hereto agree that:

Section 8.01.  Reasonable Best Efforts.  (a) Subject to the terms and conditions of this Agreement, the Company and Parent shall 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 under Law to consummate the transactions contemplated by this Agreement, including (i) making as promptly as practicable any required filings with any Governmental Authority or other third party and furnishing all information reasonably required in connection with such filings, (ii) using reasonable best efforts to cause the expiration of any applicable waiting periods, (iii) using reasonable best efforts to obtain any consent, authorization or approval of any private third Person required to be obtained by Parent, Merger Subsidiary or the Company or any of their respective Subsidiaries in connection with the transactions contemplated by this Agreement, (iv) using reasonable best efforts to prevent the entry of any judgment, injunction, order or decree that would prohibit the consummation of the Offer or the Merger and (v) taking any other actions by or with respect to any Governmental Authority or other third party that are necessary, proper or advisable to consummate the transactions contemplated by this Agreement.

(b) In furtherance and not in limitation of the foregoing, each of Parent and the Company shall make an appropriate filing pursuant to any applicable Antitrust Laws with respect to the transactions contemplated hereby as promptly as practicable, and supply as promptly as practicable any additional information or documents that may be requested and use reasonable best efforts to cause the expiration or termination of any applicable waiting periods or the taking of any other actions by or with respect to such Antitrust Laws as soon as practicable.

Section 8.02.  Cooperation. The Company and Parent shall cooperate with one another (a) in connection with the preparation of the Company Disclosure Documents and the Offer Documents, (b) in determining whether any action by or in respect of, or filing with, any Governmental Authority is required, or any actions, consents, approvals or waivers are required to be obtained from parties to any material contracts, in connection with the consummation of the transactions contemplated by this Agreement and (c) in taking such actions or making any such filings, furnishing information required in connection therewith or with the Company Disclosure Documents or the Offer Documents and seeking timely to obtain any such actions, consents, approvals or waivers.

Section 8.03.  Public Announcements.  Parent and its Affiliates, on the one hand, and the Company and its Subsidiaries, on the other hand, shall consult with each other, and use reasonable best efforts to accommodate the comments (including as to timing) of the other, before issuing any press release or making any other public statement, or scheduling any press conference or conference call with investors or analysts, with respect to this Agreement or the transactions contemplated hereby and, except as may be required by

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Law or any listing agreement with or rule of any national securities exchange, shall not issue any such press release or make any such other public statement or schedule any such press conference or conference call before such consultation. Notwithstanding anything in this Agreement to the contrary, neither Parent nor any of its Affiliates or representatives shall, without the prior consent of the Company, contact any employees in their capacity as employees (except for executive officers of the Company), customers or suppliers of the Company or its Subsidiaries, whether in person or by telephone, mail or other means of communication, prior to the Acceptance Date in connection with the transactions contemplated hereby.

Section 8.04.   Further Assurances.  At and after the Effective Time, the officers and directors of the Surviving Corporation shall be authorized to execute and deliver, in the name and on behalf of the Company or Merger Subsidiary, any deeds, bills of sale, assignments or assurances and to take and do, in the name and on behalf of the Company or Merger Subsidiary, any other actions and things to vest, perfect or confirm of record or otherwise in the Surviving Corporation any and all right, title and interest in, to and under any of the rights, properties or assets of the Company acquired or to be acquired by the Surviving Corporation as a result of, or in connection with, the Merger.

Section 8.05.  Merger Without Meeting of Stockholders.  If at any time after the Acceptance Date, Parent and its Affiliates shall own at least 90% of the outstanding Shares, the parties shall take all necessary and appropriate action to cause the Merger to be effected as soon as practicable without a meeting of stockholders of the Company in accordance with Section 253 of Delaware Law.

Section 8.06.  Section 16 Matters.  Prior to the Effective Time, the Company shall take all such steps as may be required to cause any disposition of Shares in the Merger (including derivative securities with respect to such Shares) by each individual who is subject to the reporting requirements of Section 16(a) of the 1934 Act with respect to the Company to be exempt under Rule 16b-3 promulgated under the 1934 Act.

Section 8.07.  Notices of Certain Events.  Subject to applicable Law, each of the Company and Parent shall promptly notify the other of:

(a) any notice or other communication received by the Company or any of its Subsidiaries or Parent or any of its Affiliates from any Person alleging that the consent of such Person is or may be required in connection with the transactions contemplated by this Agreement;

(b) any notice or other communication received by the Company or any of its Subsidiaries or Parent or any of its Affiliates from any Governmental Authority that relate to the transactions contemplated by this Agreement; and

(c) any actions, suits, investigations or proceedings commenced or, to its knowledge, threatened against the Company or any of its Subsidiaries or Parent or any of its Affiliates that relate to the consummation of the transactions contemplated by this Agreement.

Section 8.08.  Takeover Statutes.  If any “fair price,” “moratorium,” “control share acquisition” or other similar anti-takeover statute or regulation shall become applicable to the transactions contemplated hereby, each of the Company, Parent and Merger Subsidiary and the respective members of their boards of directors shall, to the extent permitted by applicable Law, use reasonable best efforts to grant such approvals and take such actions as are necessary so that the transactions contemplated by this Agreement may be consummated as promptly as practicable on the terms contemplated herein andotherwise act to eliminate or minimize the effects of such statute or regulation on the transactions contemplated hereby.

Section 8.09.   Litigation.  (a) Each of the parties shall promptly enter into stipulations staying all litigation currently pending between them or their respective Affiliates and representatives, or commenced by or on behalf of any of them in connection with the Offer, and the parties shall cause such stipulations to be filed promptly after the date of this Agreement. Each of the parties shall also, promptly following the Acceptance Date, enter into and file stipulations dismissing with prejudice all such litigation and releasing all claims against the other parties hereto (and their Affiliates and representatives) based on any action or omission that occurred prior to the date of such stipulations as of the date such stipulations are filed. Notwithstanding the foregoing, if this Agreement is terminated in accordance with Section 10.01, after such

28

termination, nothing herein shall prevent either party (or its Affiliates or representatives) from pursuing any such litigation or any other litigation against any other party hereto (or its Affiliates or representatives).

(b) The Company shall give Parent the opportunity to participate in the defense or settlement of any stockholder litigation that currently exists or arises after the date of this Agreement against the Company or its directors or officers relating to any of the transactions contemplated hereby.

Section 8.10.   Transfer Taxes.  Subject to Section 2.03(c), all stock transfer, real estate transfer, documentary, stamp, recording and other similar Taxes (including interest, penalties and additions to any such Taxes) (“Transfer Taxes”) incurred in connection with the transactions contemplated hereby shall be paid by either Merger Subsidiary or the Surviving Corporation, and the Company shall cooperate with Merger Subsidiary and Parent in preparing, executing and filing any Tax Returns with respect to such Transfer Taxes.

ARTICLE 9

Conditions to the Merger

Section 9.01.  Conditions to the Obligations of Each Party.  The obligations of the Company, Parent and Merger Subsidiary to consummate the Merger are subject to the satisfaction of the following conditions:

(a) if required by Delaware Law, the Company Stockholder Approval shall have been obtained;

(b) there is no Law or judgment, injunction, order or decree of any Governmental Authority with, in any such case, competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Merger; and

(c) Merger Subsidiary shall have purchased Shares pursuant to the Offer.

ARTICLE 10

Termination

Section 10.01.  Termination.  This Agreement may be terminated and the Offer and/or the Merger may be abandoned at any time prior to the Effective Time (notwithstanding receipt of the Company Stockholder Approval):

(a) by mutual written agreement of the Company and Parent;

(b) by either the Company or Parent, if:

(i) the Acceptance Date has not occurred on or before May 31, 2008 (the “End Date”); provided that the End Date shall be extended to June 30, 2008 if on May 31, 2008, none of the conditions set forth in Annex I exists other than as a result of restrictions under applicable Antitrust Laws; provided, further that the right to terminate this Agreement pursuant to this Section 10.01(b)(i) shall not be available to any party whose breach of any provision of this Agreement results in the failure of the Acceptance Date to occur on or before such time; or

(ii) if there is a Law or final, non-appealable judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Offer or the Merger;

(c) by Parent, if prior to the first acceptance for payment of Shares pursuant to the Offer:

(i) an Adverse Recommendation Change shall have occurred;

(ii) the Company shall have intentionally and materially breached its obligations under Section 6.04 (it being understood that actions taken by officers, directors or employees of the Company or its Subsidiaries or Company Representatives shall not give rise to a right to terminate the Agreement pursuant to this Section 10.01(c)(ii) so long as neither the Company nor any of its Subsidiaries has authorized or permitted any such actions by its officers, directors or employees and

29

the Company and its Subsidiaries have used their respective reasonable best efforts to cause such Company Representatives not to take any such actions); or

(iii) a breach of any representation or warranty or failure to perform any covenant or agreement on the part of the Company set forth in this Agreement shall have occurred that would cause the condition set forth in clauses (b)(ii) or (b)(iii) of Annex I to exist, and such breach or failure is incapable of being cured by the End Date;

(d) by the Company, if Parent, Merger Subsidiary or any of their Affiliates shall have breached in any material respect any of their respective representations or warranties or failed to perform in any material respect any of their respective covenants or agreements set forth in this Agreement or the Guarantee dated as of the date hereof between Holding and the Company, which breach or failure to perform is incapable of being cured by the End Date; or

(e) by the Company pursuant to Section 6.04(a)(y).

The party desiring to terminate this Agreement pursuant to this Section 10.01 (other than pursuant to Section 10.01(a)) shall give notice of such termination to the other party.

Section 10.02.    Effect of Termination.  If this Agreement is terminated pursuant to Section 10.01, this Agreement shall become void and of no effect with no liability on the part of any party (or any stockholder, director, officer, employee, agent or advisor of such party) to the other party hereto; provided that, if such termination shall result from the (a) intentional failure of either party to fulfill a condition to the performance of the obligations of the other party or (b) material breach of either party to perform a covenant hereof, such party shall be fully liable for any and all liabilities and damages incurred or suffered by the other party as a result of such failure or breach. The provisions of Article 11 shall survive any termination hereof pursuant to Section 10.01.

ARTICLE 11

Miscellaneous

Section 11.01.  Notices.  All notices, requests and other communications to any party hereunder shall be in writing (including facsimile transmission) and shall be given,

if to Parent, to:

Roche Holdings, Inc.
1220 N. Market St., Suite #334
Wilmington, Delaware 19801-2535
Attention: Carol Fiederlein
Facsimile No.: (302) 425-4713

with a copy to:

Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
Attention:  Christopher Mayer
Marc O. Williams
Facsimile No.: (212) 450-3800

if to Merger Subsidiary, to:

Rocket Acquisition Corporation
9115 Hague Road
Indianapolis, Indiana 46250
Attention: Steve A. Oldham
Facsimile No.: (317) 521-3082

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with a copy to:

Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
Attention:  Christopher Mayer
Marc O. Williams
Facsimile No.: (212) 450-3800

if to the Company, to:

Ventana Medical Systems, Inc.
1910 E. Innovation Park Drive
Tucson, Arizona 85755
Attention: Chief Executive Officer
General Counsel
Facsimile No.: (520) 229-4204

with a copy to:

Sidley Austin LLP
1 South Dearborn Street
Chicago, Illinois 60603
Attention:  Thomas A. Cole
Frederick C. Lowinger
Michael A. Gordon
Robert L. Verigan
Facsimile No.: (312) 853-7036

and to:

Snell & Wilmer LLP
One Arizona Center
400 East Van Buren
Phoenix, Arizona 85004
Attention: Daniel M. Mahoney
Facsimile No.: (602) 382-6070

or to such other address or facsimile number as such party may hereafter specify for the purpose by notice to the other parties hereto. All such notices, requests and other communications shall be deemed received on the date of receipt by the recipient thereof if received prior to 5 p.m. on a business day in the place of receipt. Otherwise, any such notice, request or communication shall be deemed to have been received on the next succeeding business day in the place of receipt.

Section 11.02.  Survival of Representations and Warranties.  The representations and warranties contained herein and in any certificate or other writing delivered pursuant hereto shall not survive the Acceptance Date.

Section 11.03.  Amendments and Waivers.  (a) Any provision of this Agreement may be amended or waived prior to the Effective Time if, but only if, such amendment or waiver is in writing and is signed, in the case of an amendment, by each party to this Agreement or, in the case of a waiver, by each party against whom the waiver is to be effective; provided that, after the Company Shareholder Approval has been obtained (if applicable), there shall be no amendment or waiver that, under Delaware law, would require the further approval of the stockholders of the Company without such approval.

(b) No failure or delay by any party in exercising any right, power or privilege hereunder shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof

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or the exercise of any other right, power or privilege. The rights and remedies herein provided shall be cumulative and not exclusive of any rights or remedies provided by Law.

Section 11.04.  Expenses.  (a) General. All costs and expenses incurred in connection with this Agreement shall be paid by the party incurring such cost or expense.

(b) Termination Fee.

(i) If this Agreement is terminated by Parent pursuant to Section 10.01(c)(i) or by the Company pursuant to Section 10.01(e), then the Company shall pay to Parent in immediately available funds $110,000,000 (the “Termination Fee”), in the case of a termination by Parent, within two Business Days after such termination and, in the case of a termination by the Company, immediately before and as a condition to such termination.

(ii) If (A) this Agreement is terminated by Parent or the Company pursuant to Section 10.01(b)(i), (B) after the date of this Agreement and prior to such termination, an Acquisition Proposal shall have been publicly announced or otherwise been communicated to the Board of Directors of the Company or its stockholders and not withdrawn and (C) within nine months following the date of such termination, the Company shall have entered into a definitive agreement with respect to or recommended to its stockholders an Acquisition Proposal or an Acquisition Proposal shall have been consummated (provided that for purposes of this clause (C), each reference to “20%” in the definition of Acquisition Proposal shall be deemed to be a reference to “50%”), then the Company shall pay to Parent in immediately available funds, concurrently with the occurrence of the applicable event described in clause (C), the Termination Fee.

The Company acknowledges that the agreements contained in this Section 11.04(b) are an integral part of the transactions contemplated by this Agreement and that, without these agreements, Parent and Merger Subsidiary would not enter into this Agreement.

(c) Each of Parent, Merger Subsidiary and the Company acknowledges and agrees that in the event Parent is entitled to receive payment of the Termination Fee, the right of Parent to receive such amounts shall constitute Parent’s and its Affiliates’ sole and exclusive remedy for, and such amounts shall constitute liquidated damages in respect of, any termination of this Agreement regardless of the circumstances giving rise to such termination.

Section 11.05.  Disclosure Schedule References and SEC Document References.  (a) The parties hereto agree that any reference in a particular Section of the Company Disclosure Schedule shall only be deemed to be an exception to (or, as applicable, a disclosure for purposes of) (i) the representations and warranties (or covenants, as applicable) of the Company that are contained in the corresponding Section of this Agreement and (ii) any other representations and warranties of the Company that are contained in this Agreement, but only if the relevance of that reference as an exception to (or a disclosure for purposes of) such representations and warranties would be reasonably apparent to a person who has read that reference and such representations and warranties, without any independent knowledge on the part of the reader regarding the matter(s) so disclosed.

(b) The parties hereto agree that any information contained in any part of any Filed SEC Document shall only be deemed to be an exception to (or a disclosure for purposes of) the Company’s representations and warranties if the relevance of that information as an exception to (or a disclosure for purposes of) such representations and warranties would be reasonably apparent to a person who has read that information concurrently with such representations and warranties, without any independent knowledge on the part of the reader regarding the matter(s) so disclosed; provided that in no event shall any information contained in any part of any Filed SEC Document entitled “Risk Factors” or containing a description or explanation of “Forward-Looking Statements” be deemed to be an exception to (or a disclosure for purposes of) any representations and warranties of the Company contained in this Agreement.

Section 11.06.   Binding Effect; Benefit; Assignment.  (a) The provisions of this Agreement shall be binding upon and shall inure to the benefit of the parties hereto and their respective successors and assigns.

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Except as provided in Section 7.03, no provision of this Agreement is intended to confer any rights, benefits, remedies, obligations or liabilities hereunder upon any Person other than the parties hereto and their respective successors and assigns.

(b) No party may assign, delegate or otherwise transfer any of its rights or obligations under this Agreement without the prior written consent of each other party hereto, except that Parent or Merger Subsidiary may transfer or assign its rights and obligations under this Agreement, in whole or from time to time in part, to one or more of its Affiliates at any time; provided that such transfer or assignment shall not relieve Parent or Merger Subsidiary of its obligations under this Agreement or prejudice the rights of stockholders to receive payment for Shares validly tendered and accepted for payment pursuant to the Offer or Shares converted into cash pursuant to the Merger.

Section 11.07.  Governing Law.  This Agreement shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law rules of such state.

Section 11.08.  Jurisdiction.  The parties hereto agree that any suit, action or proceeding seeking to enforce any provision of, or based on any matter arising out of or in connection with, this Agreement or the transactions contemplated hereby shall be brought in the Court of Chancery of the State of Delaware in and for New Castle County, Delaware or, if such court shall not have jurisdiction, in any federal court located in the State of Delaware or other Delaware state court, and each of the parties hereby irrevocably consents to the jurisdiction of such courts (and of the appropriate appellate courts therefrom) in any such suit, action or proceeding and irrevocably waives, to the fullest extent permitted by law, any objection that it may now or hereafter have to the laying of the venue of any such suit, action or proceeding in any such court or that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum. Process in any such suit, action or proceeding may be served on any party anywhere in the world, whether within or without the jurisdiction of any such court. Without limiting the foregoing, each party agrees that service of process on such party as provided in Section 11.01 shall be deemed effective service of process on such party.

Section 11.09.  WAIVER OF JURY TRIAL.  EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

Section 11.10.  Counterparts; Effectiveness.  This Agreement may be signed in any number of counterparts, each of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument. This Agreement shall become effective when each party hereto shall have received a counterpart hereof signed by all of the other parties hereto. Until and unless each party has received a counterpart hereof signed by the other party hereto, this Agreement shall have no effect and no party shall have any right or obligation hereunder (whether by virtue of any other oral or written agreement or other communication).

Section 11.11.  Entire Agreement.  This Agreement constitutes the entire agreement between the parties with respect to the subject matter of hereof and thereof and supersede all prior agreements and understandings, both oral and written, between the parties with respect to the subject matter hereof and thereof.

Section 11.12.  Severability.  If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction or other Governmental Authority to be invalid, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions of this Agreement shall remain in full force and effect and shall in no way be affected, impaired or invalidated so long as the economic or legal substance of the transactions contemplated hereby is not affected in any manner materially adverse to any party. Upon such a determination, the parties shall negotiate in good faith to modify this Agreement so as to effect the original intent of the parties as closely as possible in an acceptable manner in order that the transactions contemplated hereby be consummated as originally contemplated to the fullest extent possible.

Section 11.13.  Specific Performance.  The parties hereto agree that irreparable damage would occur if any provision of this Agreement were not performed in accordance with the terms hereof and that, except as provided in Section 11.04(c), the parties shall be entitled to an injunction or injunctions to prevent breaches of

33

this Agreement or to enforce specifically the performance of the terms and provisions hereof, in addition to any other remedy to which they are entitled at law or in equity.

ARTICLE 12

Definitions

Section 12.01.   Definitions.  (a) As used herein, the following terms have the following meanings:

“Affiliate” means, with respect to any Person, any other Person directly or indirectly controlling, controlled by or under common control with such Person;  provided  that neither Genentech, Inc., a Delaware corporation, nor Chugai Pharmaceutical Co., Ltd., a Japanese company, shall be deemed an Affiliate of Holding or any of its Subsidiaries for purposes of this Agreement, it being understood that Holding, Parent and Merger Subsidiary shall be deemed to be Affiliates of one another for purposes of this Agreement.

“Antitrust Laws” means applicable Laws that are designed to prohibit, restrict or regulate actions having the purpose or effect of monopolization or restraint of trade.

“Business Day” means a day other than Saturday, Sunday or other day on which commercial banks in New York, New York are authorized or required by Law to close.

““Code” means the Internal Revenue Code of 1986.

“Company Material Adverse Effect” means a material adverse effect on

(i) the business, operations, results of operations, assets, liabilities or financial condition of the Company and its Subsidiaries, taken as a whole, excluding any effect resulting from (A) changes in the financial or securities markets or general economic or political conditions in the United States, (B) changes (including changes of Law or regulation) or conditions generally affecting the industry in which the Company and its Subsidiaries operate and not specifically relating to or having a materially disproportionate effect on the Company and its Subsidiaries, (C) acts of war, sabotage or terrorism or natural disasters involving the United States not having a materially disproportionate effect on the Company and its Subsidiaries, (D) the announcement or consummation of the Offer or the transactions contemplated by this Agreement, or (E) any failure by the Company to meet any internal or published budgets, projections, forecasts or predictions of financial performance for any period (it being understood that this clause (E) shall not prevent a party from asserting that any fact, change, event, occurrence or effect that may have contributed to such failure independently constitutes or contributes to a Company Material Adverse Effect); or

(ii) the Company’s ability to consummate the transactions contemplated by this Agreement.

“Governmental Authority” shall mean any government, court, regulatory or administrative agency, commission or authority or other governmental instrumentality, whether domestic or foreign, federal, state or local, multinational or supranational.

“knowledge” means, with respect to the Company, the actual knowledge after reasonable inquiry of any of the persons listed in Section 12.01(a) of the Company Disclosure Schedule.

“Law” means all laws (including common law), statutes, ordinances, codes, rules and regulations of any Governmental Authorities.

“Lien” means, with respect to any property or asset, any mortgage, lien, pledge, charge, security interest, encumbrance, restriction, easement, right of way, title defect or other adverse claim of any kind in respect of such property or asset. For purposes of this Agreement, a Person shall be deemed to own subject to a Lien, any property or asset that it has acquired or holds subject to the interest of a vendor or lessor under any conditional sale agreement, capital lease or other title retention agreement relating to such property or asset.

““1933 Act” means the Securities Act of 1933.

““1934 Act” means the Securities Exchange Act of 1934.

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“Parent Material Adverse Effect” means a material adverse effect on Parent’s ability to consummate the transactions contemplated by this Agreement or to perform its obligations under this Agreement.

“Person” means an individual, corporation, partnership, limited liability company, association, trust or other entity or organization, including a Governmental Authority.

“Subsidiary” means, with respect to any Person, any entity of which securities or other ownership interests having ordinary voting power to elect a majority of the board of directors or other persons performing similar functions are at any time directly or indirectly owned by such Person.

(b) Each of the following terms is defined in the Section set forth opposite such term:

Term	Section
Acceptance Date	1.01
Acquisition Proposal	6.04
Adverse Recommendation Change	6.04
Amended Offer	Recitals
Agreement	Preamble
Board of Directors	1.02
Certificates	2.03
Company	Preamble
Company Balance Sheet	4.08
Company Balance Sheet Date	4.08
Company Board Recommendation	4.02
Company Disclosure Documents	4.09
Company Disclosure Schedule	4.01
Company ESPP	2.08
Company Financial Advisors	4.20
Company Intellectual Property	4.19
Company Performance Unit	2.07
Company Proxy Statement	5.05
Company Registered Intellectual Property	4.19
Company Representatives	6.04
Company Restricted Share	2.06
Company Rights	4.22
Company SEC Documents	4.07
Company Securities	4.05
Company Stock Option	2.05
Company Stockholder Approval	4.02
Company Stockholder Meeting	6.02
Company Subsidiary Securities	4.06
Company 10-K	4.07
Confidentiality Agreement	6.03
Continuing Director	1.03
Continuing Employees	7.04
D&O Insurance	7.03
Delaware Law	1.02
Effective Time	2.01
Employee Plans	4.16

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Term	Section
End Date	10.01
Environmental Laws	4.17
Environmental Permits	4.17
ERISA	4.16
ERISA Affiliate	4.16
Exchange Agent	2.03
Existing Offer	Recitals
Filed SEC Documents	4.01
GAAP	4.08
Hazardous Substance	4.17
Holding	6.03
Indemnified Person	7.03
Intellectual Property	4.19
International Plans	4.16
Material Contracts	4.18
Merger	2.01
Merger Consideration	2.02
Merger Subsidiary	Preamble
Minimum Condition	1.01
Multiemployer Plan	4.16
Necessary Intellectual Property	4.19
Off-the-Shelf Software	4.19
Offer	Recitals
Offer Documents	1.01
Parent	Preamble
Rights Agreement	4.22
Schedule TO	Recitals
Schedule 14D-9	1.02
SEC	1.01
Shares	Recitals
Subsequent Offering Period	1.01
Superior Proposal	6.04
Surviving Corporation	2.01
Tax	4.14
Taxing Authority	4.14
Tax Return	4.14
Termination Fee	11.04
Top-Up Notice	1.04
Top-Up Option	1.04
Top-Up Shares	1.04
Transfer Taxes	8.10
Uncertificated Shares	2.03

Section 12.02.   Other Definitional and Interpretative Provisions.  The words “hereof”, “herein” and “hereunder” and words of like import used in this Agreement shall refer to this Agreement as a whole and not

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to any particular provision of this Agreement. The captions herein are included for reference purposes only and shall be ignored in the construction or interpretation hereof. References to Articles, Sections, Exhibit, Annexes and Schedules are to Articles, Sections, Exhibit, Annexes and Schedules of this Agreement unless otherwise specified. All Exhibit, Annexes and Schedules annexed hereto or referred to herein are hereby incorporated in and made a part of this Agreement as if set forth in full herein. All terms defined in this Agreement and used but not otherwise defined in any Exhibit, Annex or Schedule or any other document made or delivered pursuant hereto shall have the meaning as defined in this Agreement. The definitions contained in this Agreement are applicable to the singular as well as the plural forms of such terms. Whenever the words “include”, “includes” or “including” are used in this Agreement, they shall be deemed to be followed by the words “without limitation”. “Writing”, “written” and comparable terms refer to printing, typing and other means of reproducing words (including electronic media) in a visible form. References to any statute shall be deemed to refer to such statute as amended from time to time and to any rules or regulations promulgated thereunder. References to any agreement or contract shall be deemed to refer to such agreement or contract as amended, modified or supplemented from time to time in accordance with the terms thereof; provided that with respect to any agreement or contract listed on any schedules hereto, all such amendments, modifications or supplements must also be listed in the appropriate schedule. References to any Person include the successors and permitted assigns of that Person.

[The remainder of this page has been intentionally left blank; the next
page is the signature page.]

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed by their respective authorized officers as of the day and year first above written.

VENTANA MEDICAL SYSTEMS, INC.

By:  /s/  Christopher M. Gleeson

Name:     Christopher M. Gleeson

Title:  President and Chief Executive Officer

ROCHE HOLDINGS, INC.

By:  /s/  Carol Fiederlein

Name:     Carol Fiederlein

Title:  Vice President and Corporate Secretary

ROCKET ACQUISITION CORPORATION

By:  /s/  Bruno Maier

Name:     Bruno Maier

Title:  President

By:  /s/  Beat Kraehenmann

Name:     Beat Kraehenmann

Title:  Secretary

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ANNEX I

Notwithstanding any other provision of this Agreement, Merger Subsidiary shall not be required to accept for payment, or pay for, any Shares, and may, subject to Article 1 and Article 10 of this Agreement, terminate the Offer, if:

(a) prior to the expiration of the Offer, (i) the Minimum Condition (as defined in the Merger Agreement) shall not have been satisfied or (ii) there are any restrictions or prohibitions under any applicable Antitrust Law (including suspensory filing requirements, waiting periods and required actions, consents or clearances by any Governmental Authority) that would make illegal the consummation of the Offer or the Merger; or

(b) at any time on or after the date of this Agreement and prior to the expiration of the Offer, any of the following conditions exists:

(i) there is a Law or judgment, injunction, order or decree of any Governmental Authority with competent jurisdiction restraining, prohibiting or otherwise making illegal the consummation of the Offer or the Merger;

(ii) (A) the representations and warranties of the Company contained in the second sentence of Section 4.05 shall not be true and correct in all material respects at and as of immediately prior to the expiration of the Offer as if made at and as of such time (other than such representations and warranties that by their terms address matters only as of another specified time, which shall be true and correct in all material respects only as of such time) or (B) the other representations and warranties of the Company contained in this Agreement (disregarding all materiality and Company Material Adverse Effect qualifications contained therein) shall not be true and correct at and as of immediately prior to the expiration of the Offer as if made at and as of such time (other than representations and warranties that by their terms address matters only as of another specified time, which shall be true and correct only as of such time), except, in the case of clause (B) only, for such matters as have not had and would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect;

(iii) the Company shall have failed to perform in all material respects all of its obligations to be performed or complied with by it under this Agreement prior to such time;

(iv) the Company shall have failed to deliver to Parent a certificate signed by an executive officer of the Company dated as of the date on which the Offer expires certifying that the conditions specified in clauses (ii) and (iii) of this paragraph (b) do not exist; or

(v) this Agreement shall have been terminated in accordance with its terms.

I-1