S-8

As filed with the Securities and Exchange Commission on May 25, 2006

Registration No. 333-      

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

CEPHALON, INC.
(Exact name of issuer as specified in its charter)

Delaware	23-2484489
(State or other jurisdiction of	(I.R.S. Employer Identification No.)
incorporation of organization)

41 Moores Road
Frazer, Pennsylvania 19355
(Address of principal executive offices)

CEPHALON, INC. 2004 EQUITY COMPENSATION PLAN
(Full title of the plan)

John E. Osborn, Esq.
Executive Vice President, General Counsel & Secretary
Cephalon, Inc.
41 Moores Road
Frazer, PA 19355
(Name and address of agent for service)

(610) 344-0200
(Telephone number, including area code, of agent for service)

Copy to:
Pran Jha, Esq.
Sidley Austin LLP
One South Dearborn
Chicago, IL 60603
(312) 853-7000

CALCULATION OF REGISTRATION FEE

Title of class of securities to be registered	Amount to be registered (1)	Proposed maximum offering price per share (2)	Proposed maximum Aggregate offering price (2)	Amount of registration fee
Common stock, $0.01 par value (3)	1,750,000 shares	$56.90	$99,575,000	$10,654.53

(1)Pursuant to Rule 416 under the Securities Act of 1933, this Registration Statement also covers such additional shares as may hereinafter be offered or issued to prevent dilution resulting from stock splits, stock dividends and similar anti-dilution provisions.

(2)Estimated pursuant to paragraphs (c) and (h) of Rule 457 solely for purposes of calculating the registration fee, based upon the average of the high and low sales price for a share of Common Stock on May 22, 2006, as reported on the Nasdaq National Market.

(3)Each share of the registrant’s common stock includes one preferred share purchase right pursuant to the Second Amended and Restated Rights Agreement dated October 27, 2003 between Cephalon, Inc. and StockTrans, Inc., as Rights Agent.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

This registration statement on Form S-8 relates to the registration of an additional 1,750,000 shares of Common Stock, $.01 par value, of the Registrant. The shares are securities of the same class and relating to the same employee benefit plan, the Cephalon, Inc. 2004 Equity Compensation Plan (previously known as the Cephalon, Inc. 1995 Equity Compensation Plan), as those shares registered in the Registrant’s registration statement on Forms S-8, previously filed with the Securities and Exchange Commission on March 28, 1996, December 23, 1998, October 29, 1999, May 28, 2002, June 13, 2003 and August 27, 2004. The earlier registration statements on Form S-8 (Registration Nos. 333-02888, 333-69591, 333-89909, 333-89230, 333-106112 and 333-118611) are hereby incorporated by reference.

Item 8.                    Exhibits.

The Exhibits accompanying this Registration Statement are listed on the accompanying Exhibit Index.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Frazer, Commonwealth of Pennsylvania, on this 25th day of May 2006.

CEPHALON, INC.
By:	/s/ Frank Baldino, Jr.
	Frank Baldino, Jr., Ph.D.
	Chairman and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Frank Baldino, Jr. and John E. Osborn, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, in any and all capacities, to sign any or all amendments (including post-effective amendments) to this Registration Statement, including any filings under Rule 462 promulgated under the Securities Act of 1933, and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities indicated on this 25th day of May 2006.

/s/ Frank Baldino, Jr.	Chairman, President and Chief Executive	May 25, 2006
Frank Baldino, Jr., Ph.D.	Officer (Principal Executive Officer)
/s/ J. Kevin Buchi	Executive Vice President and Chief Financial	May 25, 2006
J. Kevin Buchi	Officer (Principal Financial Officer and
	Principal Accounting Officer)
/s/ William P. Egan	Director	May 25, 2006
William P. Egan
/s/ Martyn D. Greenacre	Director	May 25, 2006
Martyn D. Greenacre
/s/ Vaughn M. Kailian	Director	May 25, 2006
Vaughn M. Kailian
/s/ Kevin E. Moley	Director	May 25, 2006
Kevin E. Moley
/s/ Charles A. Sanders	Director	May 25, 2006
Charles A. Sanders, M.D.
/s/ Gail R. Wilensky	Director	May 25, 2006
Gail R. Wilensky, Ph.D.
/s/ Dennis L. Winger	Director	May 25, 2006
Dennis L. Winger

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Exhibit Index

Exhibit  Number	Exhibit
4.1	Restated Certificate of Incorporation, as amended (filed as Exhibit 3.1 to Cephalon’s Annual Report on Form 10-K for the fiscal year ended December 31, 1996 and incorporated herein by reference).
4.2	Certificate of Amendment to the Restated Certificate of Incorporation as filed with the Secretary of State of Delaware on May 16, 2002 (filed as Exhibit 3.1 to Cephalon’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2002 and incorporated herein by reference).
4.3	Bylaws, as amended and restated (filed as Exhibit 3.2 to Cephalon’s Current Report on Form 8-K filed October 21, 2005 and incorporated herein by reference).
4.4	Specimen copy of stock certificate for shares of Common Stock (filed as Exhibit 4.1 to Cephalon’s Annual Report on Form 10-K for the fiscal year ended December 31, 1993 and incorporated herein by reference).
4.5	Second Amended and Restated Rights Agreement, dated as of October 27, 2003 between Cephalon, Inc. and StockTrans, Inc. as Rights Agent (filed as Exhibit 1 to Cephalon’s Form 8-A12G/A filed on October 27, 2003 and incorporated herein by reference).
4.6	Cephalon, Inc. 2004 Equity Compensation Plan, as amended and restated (filed as Exhibit 99.1 to Cephalon’s Registration Statement on Form S-8 (Registration No. 333-106112) filed on June 13, 2003 and incorporated herein by reference).
4.7	Amendment 2004 — 1 to the Cephalon, Inc. 2004 Equity Compensation Plan, effective as of May 13, 2004 (filed as Exhibit 99.1 to Cephalon’s Registration Statement on Form S-8 (Registration No. 333-118611) filed on August 27, 2004 and incorporated herein by reference).
4.8	Amendment 2006 — 1 to the Cephalon, Inc. 2004 Equity Compensation Plan, effective as of May 17, 2006 (filed as Exhibit 10.1 to Cephalon’s Current Report on Form 8-K filed on May 17, 2006 and incorporated herein by reference).
5.1*	Opinion of Sidley Austin LLP.
23.1	Consent of Sidley Austin LLP (included in its opinion filed as Exhibit 5.1 hereto).
23.2*	Consent of PricewaterhouseCoopers LLP, Philadelphia, PA.
23.3*	Consent of PricewaterhouseCoopers LLP, London, England.
24.1*	Power of Attorney (included on signature page of this Registration Statement).

*Filed herewith.

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EX-5.1

Exhibit 5.1

SIDLEY AUSTIN LLP LOGO SIDLEY AUSTIN LLP
ONE SOUTH DEARBORN
CHICAGO, IL 60603
(312) 853 7000
(312) 853 7036 FAX BEIJING
BRUSSELS
CHICAGO
DALLAS
FRANKFURT


FOUNDED 1866 GENEVA
HONG KONG
LONDON
LOS ANGELES
NEW YORK SAN FRANCISCO
SHANGHAI
SINGAPORE
TOKYO
WASHINGTON, DC

May 25, 2006

Cephalon, Inc.
41 Moores Road
Frazer, Pennsylvania 19355

Re:	Cephalon, Inc.
	Registration Statement on Form S-8

Ladies and Gentlemen:

We have acted as counsel for Cephalon, Inc., a Delaware corporation (the “Company”), in connection with the filing of a Registration Statement on Form S-8 (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Act”), relating to the registration of 1,750,000 shares of common stock, $0.01 par value per share, of the Company (“Company Stock”) to be offered to participants in the Company’s 2004 Equity Compensation Plan (the “Plan”).

We are familiar with the Certificate of Incorporation, as amended, and the By-laws of the Company and all amendments thereto and resolutions of the Board of Directors of the Company relating to the Plan and the Registration Statement.

In this connection, we have examined originals, or copies of originals certified or otherwise identified to our satisfaction, of such records of the Company and other corporate documents, have examined such questions of law and have satisfied ourselves as to such matters of fact as we have considered relevant and necessary as a basis for the opinions set forth herein. We have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, the legal capacity of all natural persons and the conformity with the original documents of any copies thereof submitted to us for our examination.

Based upon the foregoing, we are of the opinion that:

1.             The Company is duly incorporated and validly existing under the laws of the State of Delaware.

2.             Each share of Common Stock which is newly issued pursuant to the Plan will be legally issued, fully paid and non-assessable when: (i) the Registration Statement, as finally amended, shall have become effective under the Act; (ii) the Company’s Board of Directors or a duly authorized committee thereof shall have duly adopted final resolutions authorizing the issuance and sale of such share as contemplated by the Registration Statement; (iii) such share shall have been duly issued and sold in the manner contemplated by the Plan; and

(iv) a certificate representing such share shall have been duly executed, countersigned and registered and duly delivered to the purchaser thereof against payment of the agreed consideration therefor (not less than the par value thereof) in accordance with the Plan.

We do not find it necessary for the purposes of this opinion letter to cover, and accordingly we express no opinion as to the application of, the securities or blue sky laws of the various states or the District of Columbia to the sale of the Common Stock pursuant to the Plan. We assume no obligation to update or supplement this opinion letter to reflect any facts or circumstances which may hereafter come to our attention with respect to the opinions expressed above, including any change in applicable law.

This opinion letter is limited to the General Corporation Law of the State of Delaware.

We hereby consent to the filing of this opinion letter as an exhibit to the Registration Statement and to all references to our firm included in or made a part of the Registration Statement. In giving such consent, we do not thereby admit that we are within the category of persons from whom consent is required by Section 7 of the Act or the related rules promulgated by the Commission.

Very truly yours,

/s/  Sidley Austin LLP

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EX-23.2

EXHIBIT 23.2

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-8 of our report dated March 10, 2006, relating to the financial statements, financial statement schedule, management’s assessment of the effectiveness of internal control over financial reporting and the effectiveness of internal control over financial reporting, of Cephalon, Inc., which appears in Cephalon, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2005.

/s/ PricewaterhouseCoopers LLP

Philadelphia, PA
May 25, 2006

EX-23.3

EXHIBIT 23.3

CONSENT OF INDEPENDENT ACCOUNTANTS

We hereby consent to the incorporation by reference in this Registration Statement on Form S-8 of our report dated March 7, 2006, relating to the financial statements of Zeneus Holdings Limited, which appears in the current report on Form 8-K/A of Cephalon, Inc. filed on March 10, 2006.

/s/ PricewaterhouseCoopers LLP

London, England
May 25, 2006