**Exhibit10.20(f)**

**Terminationand Assignment Agreement**

Terminationand Assignment Agreement (this “**Agreement**”),****dated as of December 19, 2006, betweenDeutsche Bank AG, acting through its London Branch (“**Deutsche**”), Cephalon, Inc. (“**Cephalon**”)and each of the assignees listed on Schedule 1 hereto (each, an “**Assignee**”).

Deutsche and Cephalon have entered into a warranttransaction (the “**Warrant Transaction**”),dated June 2, 2005 and amended on June 28, 2005, relating to 19,700,214 warrantson Cephalon’s common stock, par value $0.01 per share, (“**Shares**”); a convertible note hedgetransaction (the “**Original****Note Hedge Transaction**”), dated June 2,2005 and amended on June 28, 2005, relating to Cephalon’s Convertible SeniorNotes due June 1, 2015 (the “**Notes**”);and another convertible note hedge transaction (the “**Overallotment****Note HedgeTransaction**”), dated June 28, 2005, relating to the Notes.

Deutsche and Cephalon wish to terminate in part theOriginal Note Hedge Transaction, and Deutsche wishes to assign to each Assigneeand each Assignee wishes to accept, all rights and obligations under part ofthe Warrant Transaction.

Accordingly, the parties agree as follows:—

**1.****                                      OriginalNote Hedge Transaction**

(a)                                  ***Repayment Event***.  Cephalon has repurchased $100,000,000 Notes,which constitutes a Repayment Event and an Additional Termination Event underthe Original Note Hedge Transaction. Pursuant to the terms of the Original Note Hedge Transaction, Deutscheis exercising its right to partially terminate the Original Note HedgeTransaction, and Cephalon is exercising its right to require that any amountowed by Deutsche in connection with such termination be paid in Shares.

(b)                                 ***Settlement of Additional TerminationEvent***.  Deutsche andCephalon agree that the amount owed by Deutsche in connection with the partialtermination referred to in paragraph 1(a) is the number of Shares separatelynotified to Cephalon by Deutsche, acting in its capacity as calculation agent.  Deutsche shall deliver such number of Sharesto Cephalon on December 22, 2006.

**2.****                                      Warrant****Transaction**

(a)                                  ***Assignment***.  Deutsche agrees to assign, and each Assigneeagrees to accept, all of Deutsche’s rights and obligations under the portion ofthe Warrant Transaction relating to the number of Warrants set forth oppositeeach Assignee’s name on Schedule 1 hereto (the “**Assigned Warrants**”).  Deutscheshall retain the remaining Warrants (the “**RetainedWarrants**”).

(b)                                 ***Settlement of Assignment***.  Deutsche and each Assignee agree that theamount owed by each Assignee in connection with the partial assignment referredto in paragraph 2(a) is the number of Shares set forth opposite each Assignee’sname on Schedule 1 hereto (aggregating in total, 961,105 Shares), which is dueon December 22, 2006 (the “**Assignment****Settlement Date**”).  The assignment of the Assigned Warrants shallbecome effective upon each Assignee’s delivery to Deutsche (or to Deutsche’sdesignee, which may be Cephalon) of the relevant number of Shares through thefacilities of The Depository Trust Company, free from any lien, charge, claimor other encumbrance and any other restrictions whatsoever.

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(c)                                  ***Modifications to Assigned Warrants***.  Each of the parties agree that the AssignedWarrants shall be modified as follows (and the Assigned Warrants shall beconstrued as if Cephalon had entered into a separate agreement with eachAssignee with respect to the Assigned Warrants):

(1)                                  Allreferences to “Deutsche”, “Deutsche Bank AG, London”, “Deutsche Bank AG” and “DeutscheBank AG, acting through its London Branch” in the Assigned Warrants are deemedto refer to the relevant Assignee;

(2)                                  Thesecond full paragraph (all in bolded caps), other than the definition of “ExchangeAct”, and the first full sentence of the last paragraph in Section 13 (relatingto The Financial Services Authority) are deemed deleted;

(3)                                  Fromand after the Assignment Settlement Date, Deutsche Bank AG, New York Branchshall be relieved of all its obligations as Agent under the Assigned Warrants,and all references to the Agent in the Assigned Warrants are deemed deleted;

(4)                                  Asapplied to the Assigned Warrants, the ISDA 1992 Master Agreement referred totherein shall be an ISDA 1992 Master Agreement between Assignee and Cephalon;

(5)                                  Forthe avoidance of doubt, the reference in the definition of Maximum Number ofShares to be Delivered to “the total Number of Warrants covered by thisTransaction” shall be deemed to refer to the number of Assigned Warrants; and

(6)                                  The“Repurchase Notice” provision of the Assigned Warrants shall be interpreted asif no Repurchase Notice has yet been given, the reference to the “Trade Date”in such provision refers to the Assignment Settlement Date, and the numeratorin the definition of Warrant Equity Percentage refers only to the Assigned Warrants.

(7)                                  For the avoidance of doubt, each relevant Assigneeshall be the new Calculation Agent as defined in section 2 of the Warrant and shall have the borrow protections undersection 11(c) of the Warrant; provided however in each case only with respectto the portion of the Warrants that have been assigned to such Assignee.

(d)                                 ***Modifications to Retained Warrants***.  Each of Deutsche and Cephalon agree that theRetained Warrants shall be modified as follows (and the Retained Warrants shallbe construed as if Cephalon had entered into a separate agreement with Deutschewith respect to the Retained Warrants):

(1)                                  Forthe avoidance of doubt, the reference in the definition of Maximum Number ofShares to be Delivered to “the total Number of Warrants covered by thisTransaction” shall be deemed to refer to the number of Retained Warrants; and

(2)                                  The“Repurchase Notice” provision of the Retained Warrants shall be interpreted asif no Repurchase Notice has yet been given, the reference to the “Trade Date”in such provision refers to the Assignment Settlement Date, and the numeratorin the definition of Warrant Equity Percentage refers only to the RetainedWarrants.

(e)                                  ***Assignee’s Representation,Warranties and Acknowledgments***.

(1)                                  EachAssignee represents and warrants that: (i) Assignee is an “accredited investor”within the meaning of Regulation D under the Securities Act of 1933, as amended(the “**Securities Act**”), 

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and a “qualifiedinstitutional buyer” within the meaning of Rule 144A under the Securities Act; and(ii) Assignee is acquiring the Assigned Warrants for its own account and notwith a view to the distribution thereof within the meaning of the SecuritiesAct; and

(2)                                  EachAssignee acknowledges that:  (i) theAssigned Warrants are “restricted securities” for purposes of Rule 144 underthe Securities Act; and (ii) the Assigned Warrants have not been registeredunder the Securities Act and cannot be resold unless they are registered underthe Securities Act or in a transaction exempt from or not subject to theregistration requirements of the Securities Act.

**3.****                                      Representations**

Each party represents to each other party that:—

(a)                                  ***Status.***  It is duly organized and validly existingunder the laws of the jurisdiction of its organization or incorporation and, ifrelevant under such laws, in good standing;

(b)                                 ***Powers.***  It has the power to execute and deliver thisAgreement and to perform its obligations under this Agreement and has taken allnecessary action to authorize such execution, delivery and performance;

(c)                                  ***No Violation or Conflict.***  Such execution, delivery and performance donot violate or conflict with any law applicable to it, any provision of itsconstitutional documents, any order or judgment of any court or other agency ofgovernment applicable to it or any of its assets or any contractual restrictionbinding on or affecting it or any of its assets;

(d)                                 ***Consents.***  All governmental and other consents that arerequired to have been obtained by it with respect to this Agreement have beenobtained and are in full force and effect and all conditions of any suchconsents have been complied with;

(e)                                  ***Obligations Binding.***  Its obligations under this Agreementconstitute its legal, valid and binding obligations, enforceable in accordancewith its respective terms (subject to applicable bankruptcy, reorganization,insolvency, moratorium or similar laws affecting creditors’ rights generallyand subject, as to enforceability, to equitable principles of generalapplication (regardless of whether enforcement is sought in a proceeding inequity or at law)); and

(f)                                    ***Absence of Certain Events. ***No Event of Default orPotential Event of Default or, to its knowledge, Termination Event (each asdefined in the ISDA Master Agreement referred to in the Warrant Transaction) withrespect to it has occurred and is continuing and no such event or circumstancewould occur as a result of its entering into or performing its obligationsunder this Agreement.

**4.****                                      Miscellaneous**

(a)                                  ***Entire Agreement.***  This Agreement constitutes the entireagreement and understanding of the parties with respect to its subject matterand supersedes all oral communication and prior writings with respect thereto.

(b)                                 ***Amendments.***  No amendment, modification or waiver inrespect of this Agreement will be effective unless in writing (including awriting evidenced by a facsimile transmission) and executed by each of theparties.

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(c)                                  ***Counterparts*.**  This Agreement may be executed and deliveredin counterparts (including by facsimile transmission), each of which will bedeemed an original.

(d)                                 ***Headings.***  The headings used in this Agreement are forconvenience of reference only and are not to affect the construction of or tobe taken into consideration in interpreting this Agreement.

(e)                                  ***Governing Law.***  This Agreement will be governed by andconstrued in accordance with the laws of the State of New York (withoutreference to choice of law doctrine).

(f)                                    ***Agreement Continuation.***  The Assigned Warrants and Retained Warrants,each as modified herein, shall continue in full force and effect.  All references to the Assigned Warrants inthe Assigned Warrants or any document related thereto shall for all purposesconstitute references to the Assigned Warrants as modified hereby.  All references to the Retained Warrants inthe Retained Warrants or any document related thereto shall for all purposesconstitute references to the Retained Warrants as modified hereby.

(g)                                 ***Matters relating to the Agent***

(1)                                  DeutscheBank AG, New York branch (“**DBNY**”or “**Agent**”), in its capacity asagent under this Agreement will be responsible for (i) effecting thisAgreement, (ii) issuing all required confirmations and statements to theparties, (iii) maintaining books and records relating to this Agreement inaccordance with its standard practices and procedures and in accordance withapplicable law and (iv) unless otherwise requested by Cephalon or an Assignee,as applicable, receiving, delivering, and safeguarding Cephalon’s and Assignee’sfunds and any securities in connection with this Agreement, in accordance withits standard practices and procedures and in accordance with applicable law.

(2)                                  Agentis acting in connection with this Agreement solely in its capacity as Agent forthe parties pursuant to instructions from the parties.  Agent shall have no responsibility orpersonal liability to any party arising from any failure by any other party topay or perform any obligations hereunder, or to monitor or enforce complianceby the parties with any obligation hereunder. Each of Cephalon, Deutsche and each Assignee agrees to proceed solelyagainst each other to collect or recover any securities or monies owing to itin connection with or as a result of this Agreement.  Agent shall otherwise have no liability inrespect of this Agreement, except for its gross negligence or willfulmisconduct in performing its duties as Agent.

(3)                                  Anyand all notices, demands, or communications of any kind relating to thisAgreement between Cephalon, Deutsche and each Assignee shall be transmittedexclusively through Agent at the address to be provided.

(4)                                  Thedate and time of this Agreement will be furnished by the Agent to Cephalon,Deutsche and each Assignee, if requested.

(5)                                  TheAgent will furnish to Cephalon and Assignee upon written request a statement asto the source and amount of any remuneration received or to be received by theAgent in connection with this Agreement.

(6)                                  Cephalon,Deutsche and each Assignee each represents and agrees that this Agreement issuitable for it in the light of such party’s financial situation, investmentobjectives and needs.

(h)                                 ***FSA***                       Deutsche is regulated by TheFinancial Services Authority and has entered into this Agreement as principal.

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IN WITNESS WHEREOF the parties have executed thisAgreement with effect from the date specified on the first page of thisAgreement.

DEUTSCHE BANK AG, acting through its New York branchand solely in its capacity as Agent
| By:    | Signature  illegible |   |
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| Name:  |                 |
| Title: |                 |
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| By:    | Signature  illegible |   |
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CEPHALON, INC.
| By:                                       | /s/ J. Kevin  Buchi |   |
|-------------------------------------------|---------------------|--------|
| Name: J. Kevin Buchi                      |                |
| Title: Executive Vice President & CFO |                |

 

 

DEUTSCHE BANK AG, LONDON
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| By:    | Signature  illegible |   |
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**Visium Balanced Fund, LP**
| By:    | Signature  illegible |   |
|--------|----------------------|--------|
| Name:  |                 |
| Title: |                 |

 

 

**Visium Balanced Offshore Fund,Ltd.**
| By:    | Signature  illegible |   |
|--------|----------------------|--------|
| Name:  |                 |
| Title: |                 |

 

 

**Visium Long Bias Fund, LP**
| By:    | Signature  illegible |   |
|--------|----------------------|--------|
| Name:  |                 |
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**Visium Long Bias Offshore Fund,Ltd.**
| By:    | Signature  illegible |   |
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| Name:  |                 |
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**Atlas Master Fund, Ltd**
| By:                         | /s/ Scott  Shroeder |   |
|-----------------------------|---------------------|--------|
| Name: Scott Shroeder        |                |
| Title: Authorized Signatory |                |

 

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