Exhibit 10.320

SEPARATION AGREEMENT

This Separation Agreement (this “Agreement”) is entered into between Zofia E.
Dziewanowska, M.D., Ph.D., an individual (“Executive”), and Ligand
Pharmaceuticals Incorporated, (the “Company”), effective as of the Effective
Date (as defined below).

WHEREAS, Executive is currently employed by the Company as its Vice President,
Clinical Research and Regulatory;

WHEREAS, both the Executive and the Company have determined that it is in their
mutual best interests formally and finally resolve all matters between them; and

WHEREAS, Executive and the Company desire to set forth the terms and conditions
of the foregoing arrangement.

NOW, THEREFORE, in consideration of the mutual promises herein contained, the
parties agree as follows:

1. Effective Date; Termination of Employment.

(a) Effective Date. This Agreement shall become effective upon the occurrence of
both of the following events: (i) execution of the Agreement by the Parties; and
(ii) expiration of the revocation period applicable under the Release (as
defined in Section 2(g) below) without any party thereto having given notice of
revocation. The date of the last to occur of the foregoing events shall be
referred to in this Agreement as the “Effective Date.” Until and unless both of
the foregoing events occur, this Agreement shall be null and void.

(b) Termination of Employment Status. Executive’s employment by the Company
shall terminate effective as of March 31, 2009 (the “Termination Date”),
including her position as Vice President, Clinical Research and Regulatory (and
any other titles or officer positions she may hold) of the Company (and any of
its affiliates and subsidiaries).

(c) Consulting Agreement. Following the Termination Date, Executive and the
Company intend to enter into a consulting agreement (the “Consulting Agreement”)
pursuant to which Executive will continue to provide certain services to the
Company, on the terms and conditions set forth therein.

2. Compensation.

(a) Compensation Through Termination Date. On the Termination Date, the Company
shall issue Executive her final paycheck, reflecting (i) her earned but unpaid
base salary through March 31, 2008, and (ii) all accrued, unused PTO (vacation
and sick leave) due Executive through the Termination Date. Subject to Sections
2(b) and (c) below, Executive acknowledges and agrees that with her final check,
the payment of any outstanding expense reimbursements, and the payment of any
amounts payable under any of the employee benefit plans of the Company in
accordance with the terms of such plans, Executive will have received all
monies, bonuses, commissions, expense reimbursement, vacation pay, or other
compensation she earned or was due during her employment by the Company.

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(b) Compensation on Effective Date. On the Effective Date, in consideration for
the Release and her continued compliance with Section 3 below, Executive shall
be entitled to receive a cash lump sum payment of $499,200, consisting of
(i) $332,800, representing Executive’s annual base salary as in effect
immediately prior to the Termination Date, and (ii) $166,400, representing
Executive’s maximum target bonus for 2009. In addition, for a period of twelve
(12) months following the Termination Date (or such earlier date on which the
Executive becomes employed by another employer offering substantial similar
medical benefit coverage) (the “COBRA Coverage Period”), the Company shall pay
the monthly premium Executive would be required to pay for continuation coverage
pursuant to the Consolidated Omnibus Budget Reconciliation Act of 1985, as
amended (“COBRA”) for Executive and her eligible dependents who were covered
under the Company’s health plans as of the Termination Date such that
Executive’s premiums are the same as for active employees. Executive shall be
solely responsible for all matters relating to her continuation of coverage
pursuant to COBRA, including, without limitation, her election of such coverage
and her timely payment of the employee portion of any COBRA premiums. Following
the COBRA Coverage Period, the Executive will then be responsible for paying the
full cost of continuation coverage under COBRA for the Executive and her
eligible dependents should the Executive elect to continue coverage after such
period.

(c) Stock Awards. On the Effective Date, the vesting and/or exercisability of
any outstanding unvested portions of Executive’s Stock Awards (as defined below)
shall be automatically accelerated. Following the Termination Date, the vested
Stock Awards shall be exercisable by Executive in accordance with the terms of
the Company equity plan(s) and stock award agreements pursuant to which they
were granted. With respect to Executive’s Stock Awards granted on or after
August 17, 2007, such Stock Awards may be exercised by Executive (or Executive’s
guardian or legal representative) until (i) the date that is nine (9) months
following the Termination Date, or (ii) such longer period as may be specified
in the applicable stock award agreement; provided, however, that in no event
shall any Stock Award remain exercisable beyond the original outside expiration
date of such Stock Award. In addition, with respect to Executive’s Stock Awards
granted prior to August 17, 2007, such Stock Awards may be exercised by
Executive (or Executive’s guardian or legal representative) until
(i) December 31, 2009 first occurring following the date the Stock Award would
otherwise have expired following Executive’s termination, or (ii) such longer
period as may be specified in the applicable stock award agreement; provided,
however, that in no event shall any such Stock Award remain exercisable beyond
the original outside expiration date of such Stock Award. For purposes of this
Agreement, “Stock Awards” means all stock options, stock appreciation rights,
restricted stock and such other awards granted pursuant to the Company’s stock
option and equity incentive award plans or agreements and any shares of stock
issued upon exercise thereof.

(d) Exclusive Remedy. Except as otherwise expressly required by law (e.g.,
COBRA) or as specifically provided herein, all of Executive’s rights to
compensation, benefits, and other amounts hereunder (if any) accruing after the
termination of Executive’s employment by or service to the Company shall cease
upon such termination. In addition, Executive acknowledges and agrees that she
is not entitled to any reimbursement by the Company for any taxes payable by her
as a result of the payments and benefits received by her pursuant to this
Section 2, including, without limitation, any excise tax imposed by Section 4999
of the Code.

(e) No Mitigation. Executive shall not be required to mitigate the amount of any
payment provided for in this Section 2 by seeking other employment or otherwise,
nor shall the amount of any payment or benefit provided for in this Section 2 be
reduced by any compensation earned by Executive as the result of employment by
another employer or self-employment or by retirement benefits; provided,
however, that loans, advances (other than salary advances) or other amounts owed
by Executive to the Company under a written agreement may be offset by the
Company against amounts payable to Executive under this Section 2.

 

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(f) Company Property. Executive shall immediately surrender to the Company all
lists, books and records of, or in connection with, the Company’s business, and
all other property belonging to the Company, it being distinctly understood that
all such lists, books and records, and other documents, are the property of the
Company, other than any such property that the Company determines is necessary
for Executive’s provision of consulting services pursuant to the Consulting
Agreement. The Company expressly agrees that Executive continued access to her
computer, files and office are necessary for her provision of consulting
services pursuant to the Consulting Agreement.

(g) Release. Executive’s right to receive any of the payments or other
compensation to be made to Executive pursuant to Sections 2(b) and (c) shall be
contingent on Executive providing to the Company (and failing to revoke) a full
and complete general release in the form attached hereto as Exhibit A (the
“Release”) within fifty-five (55) days following the Termination Date. In the
event the Release does not become effective (and the revocation period
thereunder expired) within the fifty-five (55) day period following the
Termination Date, Executive shall not be entitled to the aforesaid payments and
benefits.

3. Certain Covenants. Executive hereby expressly reaffirms her obligations under
the Company’s Confidentiality and Proprietary Rights Agreement, a copy of which
is attached to this Agreement as Exhibit B and incorporated herein by reference,
and agrees that such obligations shall survive the Termination Date and any
termination of her services to the Company. The Company shall be entitled to
cease all severance payments to Executive in the event of her breach of this
Section 3.

4. Nondisparagement; Confidentiality. Executive agrees that neither she nor
anyone acting by, through, under or in concert with her shall disparage or
otherwise communicate negative statements or opinions about the Company, its
board members, officers, employees or business. The Company agrees that neither
its board members nor officers shall disparage or otherwise communicate negative
statements or opinions about Executive. Except as may be required by law,
neither Executive, nor any member of Executive’s family, nor anyone else acting
by, through, under or in concert with Executive will disclose to any individual
or entity (other than Executive’s legal or tax advisors) the terms of this
Agreement.

5. Dispute Resolution.

(a) Mediation. In the event of any dispute, claim or controversy based on,
arising out of or relating to Executive’s employment or this Agreement (a
“Dispute”), the parties shall attempt to resolve the dispute in non-binding
mediation in accordance with the National Rules for the Resolution of Employment
Disputes (the “Rules”) of the American Arbitration Association (“AAA”). If the
parties are unable to agree upon a mediator, one shall be appointed by the AAA
in accordance with its Rules. Each party shall pay the fees of its own attorneys
and all other expenses connected with presenting its case. Other costs of the
mediation, including the cost of any record or transcripts of the mediation,
AAA’s administrative fees, the fee of the mediator, and all other fees and
costs, shall be borne by the Company. If the matter has not been resolved
pursuant to the aforesaid mediation procedure within thirty (30) days of the
commencement of such procedure, or such other period as the parties agree,
either party may submit the dispute to arbitration pursuant to Section 5(b)
below.

(b) Arbitration. Any Dispute not settled pursuant to Section 5(a) above shall be
settled by final and binding arbitration in San Diego, California, before a
single neutral arbitrator in accordance with the Rules of the AAA, and judgment
on the award rendered by the arbitrator may be entered in any court having
jurisdiction. Arbitration may be compelled pursuant to the California
Arbitration Act (Code of Civil Procedure §§ 1280 et seq.). If the parties are
unable to agree upon an arbitrator, one shall be appointed by the AAA in
accordance with its Rules. Each party shall pay the fees of its own attorneys,
the expenses of

 

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its witnesses and all other expenses connected with presenting its case;
provided, however, Executive and the Company agree that, to the extent permitted
by law, the arbitrator shall award reasonable attorneys’ fees to the prevailing
party; provided, further, that the prevailing party shall be reimbursed for such
fees, costs and expenses within sixty (60) days following any such award;
provided, further, that the parties’ obligations pursuant to the foregoing
provisos shall terminate on the tenth (10th) anniversary of the Termination
Date. Other costs of the arbitration, including the cost of any record or
transcripts of the arbitration, AAA’s administrative fees, the fee of the
arbitrator, and all other fees and costs, shall be borne by the Company.

(c) Other Relief. This Section 5 is intended to be the exclusive method for
resolving any and all claims by the parties against each other for payment of
damages under this Agreement or relating to Executive’s employment; provided,
however, that neither this Agreement nor the submission to mediation or
arbitration shall limit the parties’ right to seek provisional relief, including
without limitation injunctive relief, in any court of competent jurisdiction
pursuant to California Code of Civil Procedure § 1281.8 or any similar statute
of an applicable jurisdiction. Seeking any such relief shall not be deemed to be
a waiver of such party’s right to compel arbitration. Both Executive and the
Company expressly waive their right to a jury trial.

6. Litigation Cooperation. Executive agrees to provide reasonable assistance to
the Company (including the board of directors and any committees thereof) and
its counsel and accountants in any financial audits or internal investigation
involving securities, financial, accounting, or other matters, and in its
defense of, or other participation in, any administrative, judicial, or other
proceeding arising from any charge, complaint or other action which has been or
may be filed relating to the period during which Executive was employed by the
Company. The Company agrees to reimburse Executive for her reasonable expenses
incurred in connection with such cooperation within thirty (30) days after
receipt of an invoice from Executive setting forth in reasonable detail such
expenses. Notwithstanding the foregoing, the Company shall have no obligation by
virtue of this Section 6 to pay Executive for time spent by Executive in any
pending or future litigation or arbitration where Executive is a co-defendant or
party to the arbitration or litigation or with respect to which Executive
requests indemnification pursuant to Section 7. This Section 6 shall in no way
limit the Company’s obligations under Section 7 below.

7. Indemnification Agreement. The Company hereby reaffirms its obligations under
that certain Indemnification Agreement between the Company and Executive
attached hereto as Exhibit C (the “Indemnification Agreement”). The Company’s
obligations under the Indemnification Agreement shall survive Executive’s
termination of employment by or service to the Company.

8. Agreed-Upon Statement; Employment References. Any inquiries regarding
Executive from prospective employers shall be forwarded to the Chief Executive
Officer of the Company. Except as required by law or court order, the Company
shall not make any additional or inconsistent internal or public statements
regarding Executive’s termination.

9. Miscellaneous.

(a) Entire Agreement. This Agreement and the agreements referenced herein set
forth the entire agreement of the parties hereto in respect of the subject
matter contained herein and therein and supersede all prior agreements,
promises, covenants, arrangements, communications, representations or
warranties, whether oral or written, by any officer, employee or representative
of any party hereto, and any prior agreement of the parties hereto in respect of
the subject matter contained herein, including without limitation, any prior
severance agreements, any contrary or limiting provisions in any Company equity
compensation plan, that certain Change in Control Severance Agreement dated as
of August 17, 2007, and that certain offer

 

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letter dated as of March 15, 2002, between Executive and the Company, as
amended. This Agreement shall not limit in any way any obligation Executive may
have under any other agreement with or promise to the Company relating to
confidentiality, proprietary rights in technology or the assignment of interests
in any intellectual property.

(b) Assignment; Assumption by Successor. The rights of the Company under this
Agreement may, without the consent of Executive, be assigned by the Company, in
its sole and unfettered discretion, to any person, firm, corporation or other
business entity which at any time, whether by purchase, merger or otherwise,
directly or indirectly, acquires all or substantially all of the assets or
business of the Company. The Company shall require any successor (whether direct
or indirect, by purchase, merger or otherwise) to all or substantially all of
the business or assets of the Company expressly to assume and to agree to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform it if no such succession had taken place;
provided, however, that no such assumption shall relieve the Company of its
obligations hereunder. Unless expressly provided otherwise, “Company” as used
herein shall mean the Company as defined in this Agreement and any successor to
its business and/or assets as aforesaid which assumes and agrees to perform this
Agreement by operation of law or otherwise. Executive shall not be entitled to
assign any of Executive’s rights or obligations under this Agreement. This
Agreement shall inure to the benefit of and be enforceable by Executive’s
personal or legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.

(c) Survival. The covenants, agreements, representations and warranties
contained in or made in Sections 2, 3, 4, 5, 6, 7, 8 and 9 of this Agreement
shall survive any termination of Executive’s services or any termination of this
Agreement.

(d) Third-Party Beneficiaries. This Agreement does not create, and shall not be
construed as creating, any rights enforceable by any person not a party to this
Agreement.

(e) Notices. Any notice required or permitted by this Agreement shall be in
writing and shall be delivered as follows with notice deemed given as indicated:
(i) by personal delivery when delivered personally; (ii) by overnight courier
upon written verification of receipt; (iii) by telecopy or facsimile
transmission upon acknowledgment of receipt of electronic transmission; or
(iv) by certified or registered mail, return receipt requested, upon
verification of receipt. Notice shall be sent to Executive at the address set
forth on the signature page below and to the Company at its principal place of
business, or such other address as either party may specify in writing.

(f) Severability. In the event any provision of this Agreement is found to be
unenforceable by an arbitrator or court of competent jurisdiction, such
provision shall be deemed modified to the extent necessary to allow
enforceability of the provision as so limited, it being intended that the
parties shall receive the benefit contemplated herein to the fullest extent
permitted by law. If a deemed modification is not satisfactory in the judgment
of such arbitrator or court, the unenforceable provision shall be deemed
deleted, and the validity and enforceability of the remaining provisions shall
not be affected thereby.

(g) Governing Law and Venue. This Agreement will be governed by and construed in
accordance with the laws of the United States and the State of California
applicable to contracts made and to be performed wholly within such State, and
without regard to the conflicts of laws principles thereof. Any suit brought
hereon shall be brought in the state or federal courts sitting in San Diego,
California, the Parties hereby waiving any claim or defense that such forum is
not convenient or proper. Each party hereby agrees that any such court shall
have in personam jurisdiction over it and consents to service of process in any
manner authorized by California law.

 

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(h) Counterparts. This Agreement may be executed in multiple counterparts, each
of which shall be deemed to be an original but all of which together shall
constitute one and the same instrument.

(i) Interpretation; Construction. The headings set forth in this Agreement are
for convenience only and shall not be used in interpreting this Agreement. This
Agreement has been drafted by legal counsel representing the Company, but
Executive has participated in the negotiation of its terms. Furthermore,
Executive acknowledges that Executive has had an opportunity to review and
revise the Agreement and have it reviewed by legal counsel, if desired, and,
therefore, the normal rule of construction to the effect that any ambiguities
are to be resolved against the drafting party shall not be employed in the
interpretation of this Agreement. Either party’s failure to enforce any
provision of this Agreement shall not in any way be construed as a waiver of any
such provision, or prevent that party thereafter from enforcing each and every
other provision of this Agreement.

(j) Code Section 409A. The compensation and benefits payable under this
Agreement, including without limitation the severance benefits described in
Section 2, are not intended to constitute “nonqualified deferred compensation”
within the meaning of Section 409A of the Code. To the extent applicable, this
Agreement shall be interpreted in accordance with Code Section 409A and
Department of Treasury regulations and other interpretive guidance issued
thereunder.

(k) Amendment. This Agreement may be amended or modified only with the written
consent of Executive and an authorized representative of the Company. No oral
waiver, amendment or modification will be effective under any circumstances
whatsoever.

(l) Taxes. All compensation payable to Executive under this Agreement shall be
subject to such deductions as the Company is from time to time required to make
pursuant to law, governmental regulation or order. Executive acknowledges that
the payments and benefits provided in this Agreement may have tax ramifications
to her. The Company has provided no tax or other advice to Executive on such
matters and Executive is free to consult with an accountant, legal counsel, or
other tax advisor regarding the tax consequences she may face.

(m) RIGHT TO ADVICE OF COUNSEL. EXECUTIVE ACKNOWLEDGES THAT SHE HAS THE RIGHT,
AND IS ENCOURAGED, TO CONSULT WITH HER LAWYER; BY HER SIGNATURE BELOW, EXECUTIVE
ACKNOWLEDGES THAT SHE HAS CONSULTED, OR HAS ELECTED NOT TO CONSULT, WITH HER
LAWYER CONCERNING THIS AGREEMENT.

(Signature Page Follows)

 

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first set forth above.

 

LIGAND PHARMACEUTICALS INCORPORATED By:   /s/ John Sharp Print Name:   John
Sharp Title:   Vice President, Finance and CFO ZOFIA E. DZIEWANOWSKA, M.D.,
PH.D. /s/ Zofia E. Dziewanowska Print Name:   Zofia E. Dziewanowska Address:  
765 Bonair Place   La Jolla, CA 92037

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EXHIBIT A

GENERAL RELEASE OF CLAIMS

This General Release of Claims (“Release”) is entered into as of this
             day of                 , 2009, between Zofia E. Dziewanowska
(“Executive”), and Ligand Pharmaceuticals Incorporated, a Delaware corporation
(the “Company”) (collectively referred to herein as the “Parties”).

WHEREAS, Executive and the Company are parties to that certain Separation
Agreement dated as of March 27, 2009 (the “Agreement”);

WHEREAS, the Parties agree that Executive is entitled to certain severance
benefits under the Agreement, subject to Executive’s execution of this Release;
and

WHEREAS, the Company and Executive now wish to fully and finally to resolve all
matters between them.

NOW, THEREFORE, in consideration of, and subject to, the severance benefits
payable to Executive pursuant to the Agreement, the adequacy of which is hereby
acknowledged by Executive, and which Executive acknowledges that she would not
otherwise be entitled to receive, Executive and the Company hereby agree as
follows:

1. General Release of Claims by Executive.

(a) Executive, on behalf of herself and her executors, heirs, administrators,
representatives and assigns, hereby agrees to release and forever discharge the
Company and all predecessors, successors and their respective parent
corporations, affiliates, related, and/or subsidiary entities, and all of their
past and present investors, directors, shareholders, officers, general or
limited partners, employees, attorneys, agents and representatives, and the
employee benefit plans in which Executive is or has been a participant by virtue
of her employment with or service to the Company (collectively, the “Company
Releasees”), from any and all claims, debts, demands, accounts, judgments,
rights, causes of action, equitable relief, damages, costs, charges, complaints,
obligations, promises, agreements, controversies, suits, expenses, compensation,
responsibility and liability of every kind and character whatsoever (including
attorneys’ fees and costs), whether in law or equity, known or unknown, asserted
or unasserted, suspected or unsuspected (collectively, “Claims”), which
Executive has or may have had against such entities based on any events or
circumstances arising or occurring on or prior to the date hereof or on or prior
to the date hereof, arising directly or indirectly out of, relating to, or in
any other way involving in any manner whatsoever Executive’s employment by or
service to the Company or the termination thereof, including any and all claims
arising under federal, state, or local laws relating to employment, including
without limitation claims of wrongful discharge, breach of express or implied
contract, fraud, misrepresentation, defamation, or liability in tort, and claims
of any kind that may be brought in any court or administrative agency including,
without limitation, claims under Title VII of the Civil Rights Act of 1964, as
amended, 42 U.S.C. Section 2000, et seq.; the Americans with Disabilities Act,
as amended, 42 U.S.C. § 12101 et seq.; the Rehabilitation Act of 1973, as
amended, 29 U.S.C. § 701 et seq.; the Civil Rights Act of 1866, and the Civil
Rights Act of 1991; 42 U.S.C. Section 1981, et seq.; the Age Discrimination in
Employment Act, as amended, 29 U.S.C. Section 621, et seq. (the “ADEA”); the
Equal Pay Act, as amended, 29 U.S.C. Section 206(d); regulations of the Office
of Federal Contract Compliance, 41 C.F.R. Section 60, et seq.; the Family and
Medical Leave Act, as amended, 29 U.S.C. § 2601 et seq.; the Fair Labor
Standards Act of 1938, as amended, 29 U.S.C. § 201 et seq.; the Employee
Retirement Income Security Act, as amended, 29 U.S.C. § 1001 et seq.; and the
California Fair Employment and Housing Act, California Government Code
Section 12940, et seq.

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Notwithstanding the generality of the foregoing, Executive does not release the
following claims:

(i) Claims for unemployment compensation or any state disability insurance
benefits pursuant to the terms of applicable state law;

(ii) Claims for workers’ compensation insurance benefits under the terms of any
worker’s compensation insurance policy or fund of the Company;

(iii) Claims pursuant to the terms and conditions of the federal law known as
COBRA;

(iv) Claims for indemnity under the bylaws of the Company, as provided for by
Delaware law or under any applicable insurance policy with respect to
Executive’s liability as an employee, director or officer of the Company;

(v) Claims based on any right Executive may have to enforce the Company’s
executory obligations under the Agreement; and

(vi) Claims Executive may have to vested or earned compensation and benefits.

(b) EXECUTIVE ACKNOWLEDGES THAT SHE HAS BEEN ADVISED OF AND IS FAMILIAR WITH THE
PROVISIONS OF CALIFORNIA CIVIL CODE SECTION 1542, WHICH PROVIDES AS FOLLOWS:

“A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR
SUSPECT TO EXIST IN HIS OR HER FAVOR AT THE TIME OF EXECUTING THE RELEASE,
WHICH, IF KNOWN BY HIM OR HER, MUST HAVE MATERIALLY AFFECTED HIS OR HER
SETTLEMENT WITH THE DEBTOR.”

BEING AWARE OF SAID CODE SECTION, EXECUTIVE HEREBY EXPRESSLY WAIVES ANY RIGHTS
SHE MAY HAVE THEREUNDER, AS WELL AS UNDER ANY OTHER STATUTES OR COMMON LAW
PRINCIPLES OF SIMILAR EFFECT.

(c) Executive acknowledges that this Release was presented to her on the date
indicated above and that Executive is entitled to have twenty-one (21) days’
time in which to consider it. Executive further acknowledges that the Company
has advised her that she is waiving her rights under the ADEA, and that
Executive may obtain advice concerning this Release from an attorney of her
choice, and Executive has had sufficient time to consider the terms of this
Release. Executive represents and acknowledges that if Executive executes this
Release before twenty-one (21) days have elapsed, Executive does so knowingly,
voluntarily, and upon the advice and with the approval of Executive’s legal
counsel (if any), and that Executive voluntarily waives any remaining
consideration period.

(d) Executive understands that after executing this Release, Executive has the
right to revoke it within seven (7) days after her execution of it. Executive
understands that this Release will not become effective and enforceable unless
the seven (7) day revocation period passes and Executive does not revoke the
Release in writing. Executive understands that this Release may not be revoked
after the seven (7) day revocation period has passed. Executive also understands
that any revocation of this Release must be made in writing and delivered to the
Company at its principal place of business within the seven (7) day period.

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(e) Executive understands that this Release shall become effective, irrevocable,
and binding upon Executive on the eighth (8th) day after my execution of it, so
long as Executive has not revoked it within the time period and in the manner
specified in clause (d) above. Executive further understands that Executive will
not be given any severance benefits under the Agreement until the effective date
of this Release.

2. No Assignment. Executive represents and warrants to the Company Releasees
that there has been no assignment or other transfer of any interest in any Claim
that Executive may have against the Company Releasees, or any of them. Executive
agrees to indemnify and hold harmless the Company Releasees from any liability,
claims, demands, damages, costs, expenses and attorneys’ fees incurred as a
result of any such assignment or transfer from Executive.

3. Severability. In the event any provision of this Release is found to be
unenforceable by an arbitrator or court of competent jurisdiction, such
provision shall be deemed modified to the extent necessary to allow
enforceability of the provision as so limited, it being intended that the
parties shall receive the benefit contemplated herein to the fullest extent
permitted by law. If a deemed modification is not satisfactory in the judgment
of such arbitrator or court, the unenforceable provision shall be deemed
deleted, and the validity and enforceability of the remaining provisions shall
not be affected thereby.

4. Interpretation; Construction. The headings set forth in this Release are for
convenience only and shall not be used in interpreting this Agreement. This
Release has been drafted by legal counsel representing the Company, but
Executive has participated in the negotiation of its terms. Furthermore,
Executive acknowledges that Executive has had an opportunity to review and
revise the Release and have it reviewed by legal counsel, if desired, and,
therefore, the normal rule of construction to the effect that any ambiguities
are to be resolved against the drafting party shall not be employed in the
interpretation of this Release. Either party’s failure to enforce any provision
of this Release shall not in any way be construed as a waiver of any such
provision, or prevent that party thereafter from enforcing each and every other
provision of this Release.

5. Governing Law and Venue. This Release will be governed by and construed in
accordance with the laws of the United States of America and the State of
California applicable to contracts made and to be performed wholly within such
State, and without regard to the conflicts of laws principles thereof. Any suit
brought hereon shall be brought in the state or federal courts sitting in San
Diego, California, the Parties hereby waiving any claim or defense that such
forum is not convenient or proper. Each party hereby agrees that any such court
shall have in personam jurisdiction over it and consents to service of process
in any manner authorized by California law.

6. Entire Agreement. This Release and the Agreement constitute the entire
agreement of the Parties in respect of the subject matter contained herein and
therein and supersede all prior or simultaneous representations, discussions,
negotiations and agreements, whether written or oral. This Release may be
amended or modified only with the written consent of Executive and an authorized
representative of the Company. No oral waiver, amendment or modification will be
effective under any circumstances whatsoever.

7. Counterparts. This Release may be executed in multiple counterparts, each of
which shall be deemed to be an original but all of which together shall
constitute one and the same instrument.

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IN WITNESS WHEREOF, and intending to be legally bound, the Parties have executed
the foregoing Release as of the date first written above.

 

EXECUTIVE     LIGAND PHARMACEUTICALS INCORPORATED       By:     Zofia E.
Dziewanowska, M.D., Ph.D.     Print Name:         Title:    

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EXHIBIT B

COMPANY CONFIDENTIALITY AND PROPRIETARY RIGHTS AGREEMENT

[Attached]

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EXHIBIT C

INDEMNIFICATION AGREEMENT

[Attached]