Exhibit 10.1

Confidential                

AGREEMENT

AGREEMENT made and entered into in New York, New York, by and between Antigenics
Inc. (the “Company”), a Delaware corporation with a principal place of business
at 162 Fifth Ave Suite 900 New York, NY, and Karen Higgins Valentine (the
“Executive”), effective as of the 16th day of September, 2008 (the “Effective
Date”) (the “Agreement”). Words or phrases which are initially capitalized or
are within quotation marks shall have the meanings provided in Section 14 below
and as provided elsewhere herein.

WHEREAS, the operations of the Company and its Affiliates are a complex matter
requiring direction and leadership in a variety of arenas;

WHEREAS, the Executive is possessed of certain experience and expertise that
qualify him/her to provide the direction and leadership required by the Company;
and

WHEREAS, subject to the terms and conditions hereinafter set forth, the Company
therefore wishes to employ the Executive and the Executive wishes to accept such
employment;

NOW, THEREFORE, in consideration of the foregoing premises and the mutual
promises, terms, provisions and conditions set forth in this Agreement, the
parties hereby agree:

1. Employment. Subject to the terms and conditions set forth in this Agreement,
the Company hereby offers and the Executive hereby accepts employment.

2. Term. Subject to earlier termination as hereafter provided, this Agreement
shall have an original term of one year commencing on the Effective Date hereof
and shall be automatically extended thereafter for successive terms of one year
each, unless either party provides notice to the other at least ninety (90) days
prior to the expiration of the original or any extension term this Agreement is
not to be extended. The term of this Agreement, as from time to time extended or
renewed, is hereafter referred to as “Term”.

3. Capacity and Performance.

(a) During the Term hereof, the Executive shall be employed by the Company on a
full-time basis and shall perform such duties and responsibilities on behalf of
the Company and its Affiliates as may be designated from time to time consistent
with his/her position. In addition, and without further compensation, the
Executive shall serve as a director and/or officer of one or more of the
Company’s Affiliates if so elected or appointed from time to time.

(b) During the Term hereof, the Executive shall devote his/her best efforts,
business judgment, skill and knowledge to the advancement of the business and
interests of the Company and its Affiliates and to the discharge of his/her
duties and responsibilities hereunder. The Executive shall not engage in any
other business activity or serve in any industry, trade, professional,
governmental or academic position during the Term of this Agreement, except as
may be approved by the Board of Directors of the Company (the “Board”) or its
designee.

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4. Compensation and Benefits. As compensation for all services performed by the
Executive under and during the Term hereof and subject to performance of the
Executive’s duties and of the obligations of the Executive to the Company and
its Affiliates, pursuant to this Agreement or otherwise:

(a) Base Salary. During the Term hereof, the Company shall pay the Executive a
minimum base salary at the rate of $220,000 per annum, payable in accordance
with the payroll practices of the Company for its executives and subject to
increase by the Board, in its sole discretion. Such base salary, as from time to
time increased, is hereafter referred to as the “Base Salary”. The Board shall
review the Base Salary no less than annually.

(b) Incentive and Bonus Compensation. During the Term hereof, the Executive
shall be entitled to participate in the Company’s Executive Incentive Plan to
the extent eligible and in accordance with the terms thereof, as such terms may
be modified or amended by the Company from time to time; provided, however, that
nothing contained herein shall obligate the Company to continue such incentive
compensation program. The Executive’s target incentive bonus under the Executive
Incentive Plan is 30% of his/her Base Salary. Such target may be modified by the
Company from time to time, in its sole discretion. Any compensation paid to the
Executive under the Executive Incentive Plan shall be in addition to the Base
Salary.

(c) Stock Options. The Executive has been granted options to purchase shares of
common stock of the Company. At the discretion of the Compensation Committee of
the Board, the Executive may be granted additional options to purchase shares of
stock of the Company in the future. Any existing or future grants, shall be
governed by the terms of the applicable Company stock option plan, as amended
from time to time, and any stock option certificate, stock option agreement, and
other restrictions generally applicable to Company stock options.

(d) Vacations. During the Term hereof, the Executive shall be entitled to four
weeks of vacation per annum, to be taken at such times and intervals as shall be
determined by the Executive, subject to the reasonable business needs of the
Company.

(e) Other Benefits. During the Term hereof and subject to any contribution
therefor generally required of employees (including executives) of the Company,
the Executive shall be entitled to participate in any and all employee benefit
plans from time to time in effect for employees of the Company generally, except
to the extent such plans are in a category of benefit otherwise provided to the
Executive. Such participation shall be subject to (i) the terms of the
applicable plan documents, (ii) generally applicable Company policies and
(iii) the discretion of the Board or any administrative or other committee
provided for in or contemplated by such plan. The Company may alter, modify, add
to or delete its employee benefit plans at any time as it, in its sole judgment,
determines to be appropriate, without recourse by the Executive.

(f) Business Expenses. The Company shall pay or reimburse the Executive for all
reasonable, customary and necessary business expenses incurred or paid by the
Executive

 

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in the performance of his/her duties and responsibilities hereunder, subject to
any maximum annual limit and other restrictions on such expenses as set forth in
the Company’s Travel Policy as may be amended from time to time, and to such
reasonable substantiation and documentation as may be specified by the Company
from time to time.

5. Termination of Employment and Severance Benefits. Notwithstanding the
provisions of Section 2 hereof, but subject to Section 6 hereof, the Executive’s
employment hereunder shall terminate prior to the expiration of the Term under
the following circumstances:

(a) Death. In the event of the Executive’s death during the Term hereof, the
Executive’s employment hereunder shall immediately and automatically terminate.
In the event of the Executive’s death during the Term hereof, the Company shall
pay to the Executive’s designated beneficiary or, if no beneficiary has been
designated by the Executive, to his/her estate, any earned and unpaid Base
Salary and accrued but unused vacation through the date of his/her death.

(b) Disability.

(i) The Company may terminate the Executive’s employment hereunder, upon notice
to the Executive, in the event that the Executive becomes disabled during
his/her employment hereunder through any illness, injury, accident or condition
of either a physical or psychological nature and, as a result, is unable to
perform substantially all of his/her duties and responsibilities hereunder, with
or without a reasonable accommodation, for ninety (90) days during any period of
three hundred and sixty-five (365) consecutive calendar days.

(ii) The Board may designate another employee to act in the Executive’s place
during any period of the Executive’s disability. Notwithstanding any such
designation, the Executive shall continue to receive the Base Salary in
accordance with Section 4(a) and benefits in accordance with Section 4(e), to
the extent permitted by the then-current terms of the applicable benefit plans,
until the Executive becomes eligible for disability income benefits under the
Company’s disability income plan or until the termination of his/her employment,
whichever shall first occur.

(iii) While receiving disability income payments under the Company’s disability
income plan, the Executive shall not be entitled to receive any Base Salary
under Section 4(a) hereof, but shall continue to participate in Company benefit
plans in accordance with Section 4(e) and the terms of such plans, until the
termination of his/her employment.

(iv) If any question shall arise as to whether during any period the Executive
is disabled through any illness, injury, accident or condition of either a
physical or psychological nature so as to be unable to perform substantially all
of his/her duties and responsibilities hereunder, the Executive may, and at the
request of the Company shall, submit to a medical examination by a physician
selected by the Company to whom the Executive or his/her duly appointed
guardian, if any, has no reasonable

 

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objection to determine whether the Executive is so disabled and such
determination shall for the purposes of this Agreement be conclusive of the
issue. If such question shall arise and the Executive shall fail to submit to
such medical examination, the Company’s determination of the issue shall be
binding on the Executive.

(v) In the event the Company terminates the Executive’s employment hereunder due
to disability, the Company shall pay to the Executive any accrued and unpaid
Base Salary and accrued but unused vacation through the date of termination.

(c) By the Company for Cause. The Company may terminate the Executive’s
employment hereunder for Cause at any time upon fourteen (14) day notice to the
Executive setting forth in reasonable detail the nature of such Cause. The
following, as determined by the Company in its reasonable judgment, shall
constitute Cause for termination:

(i) The Executive’s failure to perform (other than by reason of disability), or
negligence in the performance of, his/her duties and responsibilities to the
Company or any of its Affiliates; or

(ii) Material breach by the Executive of any provision of this Agreement; or

(iii) Other conduct by the Executive that is materially harmful to the business,
interests or reputation of the Company or any of its Affiliates.

Upon the giving of notice of termination of the Executive’s employment hereunder
for Cause, the Company shall have no further obligation or liability to the
Executive, other than for Base Salary earned and unpaid and accrued vacation
earned but not taken at the date of termination.

(d) By the Company Other than for Cause. The Company may terminate the
Executive’s employment with the Company other than for Cause at any time upon
notice to the Executive. In the event of such termination, the Company shall
either (i) pay the Executive the benefits payable under an executive severance
plan, if such a plan is in place on the date of termination and if the Executive
is eligible for such benefits under such a plan or, if the present value to the
Executive is greater, (ii) continue to pay the Executive his Base Salary, at the
rate in effect on the date of termination, until the conclusion of a period of
twelve (12) months following the date of termination. In addition, the Company
shall pay to the Executive in one lump sum an amount equal to the higher of
(x) the Executive’s target incentive bonus under the Executive Incentive Plan
for the year in which the Executive’s employment is terminated or (y) the actual
incentive bonus paid to the Executive, if any, under the Executive Incentive
Plan for the last full fiscal year preceding the year in which the Executive’s
employment is terminated; and shall also, until the conclusion of a period of
twelve (12) months following the date of termination, pay the full premium cost
of the Executive’s participation in the Company’s group medical and dental
insurance plans, provided that the Executive is entitled to continue such
participation under applicable law and plan terms. The Company will also provide
the Executive with an outplacement assistance benefit in the form of a lump-sum
payment of $15,000 plus an

 

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additional lump-sum payment in an amount sufficient, after giving effect to all
federal, state and other taxes with respect to such additional payment, to make
Executive whole for all taxes (including withholding taxes) on such outplacement
assistance benefit. Furthermore, at the sole discretion of the Compensation
Committee of the Board, any unvested options to purchase Company stock may be
accelerated.

(e) By the Executive for Reduction in Salary or Benefits. The Executive may
terminate his/her employment hereunder based on a material reduction in Base
Salary or benefits due in accordance with the terms of this Agreement
(“Compensation Reduction”), provided that Executive provides notice to the
Company setting forth in reasonable detail the nature of such Compensation
Reduction, and provided further that the Company shall have thirty (30) days
from such notice to cure such reduction. In the event of termination in
accordance with this Section 5(e), the Company shall either (i) pay the
Executive the benefits payable under an executive severance plan, if such a plan
is in place on the date of termination and if the Executive is eligible for such
benefits under such a plan or, if the present value to the Executive is greater,
(ii) continue to pay the Executive his Base Salary, at the rate in effect on the
date of termination, until the conclusion of a period of twelve (12) months
following the date of termination. In addition, the Company shall pay to the
Executive in one lump sum an amount equal to the higher of (x) the Executive’s
target incentive bonus under the Executive Incentive Plan for the year in which
the Executive’s employment is terminated or (y) the actual incentive bonus paid
to the Executive, if any, under the Executive Incentive Plan for the last full
fiscal year preceding the year in which the Executive’s employment is
terminated; and shall also, until the conclusion of a period of twelve
(12) months following the date of termination, pay the full premium cost of the
Executive’s participation in the Company’s group medical and dental insurance
plans, provided that the Executive is entitled to continue such participation
under applicable law and plan terms. The Company will also provide the Executive
with an outplacement assistance benefit in the form of a lump-sum payment of
$15,000 plus an additional lump-sum payment in an amount sufficient, after
giving effect to all federal, state and other taxes with respect to such
additional payment, to make Executive whole for all taxes (including withholding
taxes) on such outplacement assistance benefit. In addition, at the sole
discretion of the Compensation Committee of the Board, any unvested options to
purchase Company stock may be accelerated.

(f) By the Executive Other than for a Compensation Reduction. The Executive may
terminate his/her employment hereunder at any time upon sixty (60) days’ notice
to the Company, unless such termination would violate any obligation of the
Executive to the Company under a separate severance agreement. In the event of
termination of the Executive pursuant to this Section 5(f), the Board may elect
to waive the period of notice, or any portion thereof, and, if the Board so
elects, the Company will pay the Executive his/her Base Salary for the notice
period (or for any remaining portion of the period).

(g) Upon a Change of Control.

(i) If a Change of Control occurs on the date of such Change in Control,
fifty-percent (50%) of any stock options previously granted to the Executive
that

 

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are outstanding and unvested as of that date shall become vested and
exercisable, provided that the Executive is employed by the Company on the date
of such Change in Control.

(ii) If a Change of Control occurs and within eighteen (18) months following
such Change of Control, the Company terminates the Executive’s employment other
than for Cause, or the Executive terminates his/her employment as a result of a
Compensation Reduction or for Good Reason (as defined herein), then, in lieu of
any payments to or on behalf of the Executive under Section 5(d) or 5(e) hereof,
the Company shall pay to the Executive in one lump sum an amount equal to
(A) eighteen (18) months Base Salary at the rate in effect on the date of
termination, plus (B) 150% of the higher of (x) the Executive’s target incentive
bonus under the Executive Incentive Plan for the year in which the Executive’s
employment is terminated or (y) the actual incentive bonus paid to the
Executive, if any, under the Executive Incentive Plan for the last full fiscal
year preceding the year in which the Executive’s employment is terminated; and
shall also, until the conclusion of a period of eighteen (18) months following
the date of termination, pay the full premium cost of the Executive’s
participation in the Company’s group medical and dental insurance plans,
provided that the Executive is entitled to continue such participation under
applicable law and plan terms. In addition, any outstanding unvested options
granted to the Executive as of the date of the Change in Control shall become
vested and shall be exercisable for ninety (90) days following termination of
the Executive’s employment. The Company will also provide the Executive with an
outplacement assistance benefit in the form of a lump-sum payment of $15,000
plus an additional lump-sum payment in an amount sufficient, after giving effect
to all federal, state and other taxes with respect to such additional payment,
to make Executive whole for all taxes (including withholding taxes) on such
outplacement assistance benefit.

(iii) All payments required to be made by the Company hereunder to Executive or
his/her dependents, beneficiaries, or estate will be subject to the withholding
of such amounts relating to tax and/or other payroll deductions as may be
required by law.

In the event that it is determined that any payment or benefit provided by the
Company to or for the benefit of Executive, either under this Agreement or
otherwise, will be subject to the excise tax imposed by Section 4999 of the
Internal Revenue Code or any successor provision(s) (“Section 4999”), the
Company will, prior to the date on which any amount of the excise tax must be
paid or withheld, make an additional lump-sum payment (the “Gross-up Payment”)
to Executive in an amount sufficient, after giving effect to all federal, state
and other taxes and charges (including interest and penalties, if any) with
respect to the gross-up payment, to make Executive whole for all taxes
(including withholding taxes) and any associated interest and penalties, imposed
under or as a result of Section 4999.

 

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Determinations under this Section 5(g)(iii) will be made by an accounting firm
engaged by the Company (the “Firm”). The determinations of the Firm will be
binding upon the Company and Executive except as the determinations are
established in resolution (including by settlement) of a controversy with the
Internal Revenue Service to have been incorrect. All fees and expenses of the
Firm will be paid by the Company.

If the Internal Revenue Service asserts a claim that, if successful, would
require the Company to make a Gross-up Payment or an additional Gross-up
Payment, the Company and Executive will cooperate fully in resolving the
controversy with the Internal Revenue Service. The Company will make or advance
such Gross-up Payments as are necessary to prevent Executive from having to bear
the cost of payments made to the Internal Revenue Service in the course of, or
as a result of, the controversy. The Firm will determine the amount of such
Gross-up Payments or advances and will determine after final resolution of the
controversy whether any advances must be returned by Executive to the Company.
The Company will bear all expenses of the controversy and will gross Executive
up for any additional taxes that may be imposed upon Executive as a result of
its payment of such expenses.

(iv) For the purpose of this Section 5(g), a “Change in Control” shall mean:
(A) the acquisition by any Organization of beneficial ownership (within the
meaning of Rule 13d-3 promulgated under the Exchange Act) of 50% or more of the
common stock of the Company; provided, however, that for purposes of this
subsection (A), an acquisition shall not constitute a Change in Control if it
is: (x) by a Benefit Plan sponsored or maintained by the Company or an entity
controlled by the Company or (y) by an entity pursuant to a transaction that
complies with clauses (x), (y) and (z) of subsection (C) of this
Section 5(g)(iv); or (B) individuals who, as of September 11, 2008, constitute
the Board (the “Incumbent Board”) cease for any reason to constitute at least a
majority of the Board; provided, however, that any individual becoming a
director subsequent to September 11, 2008 whose election, or nomination for
election by the Company’s stockholders, was approved by a vote of at least a
majority of the directors then comprising the Incumbent Board (or a majority of
the members of a nominating committee who are members of the Incumbent Board)
shall be treated as a member of the Incumbent Board unless he or she assumed
office as a result of an actual or threatened election contest with respect to
the election or removal of directors or other actual or threatened solicitation
of proxies or consents by or on behalf of an Organization other than the Board;
or (C) consummation of a merger or consolidation involving the Company, or a
sale or other disposition of all or substantially all of the assets of the
Company, (a “transaction”) in each case unless, immediately following such
transaction, (x) the beneficial owners of the common stock of the Company
outstanding immediately prior to such transaction beneficially own, directly or
indirectly, more than 50% of the combined voting power of the outstanding voting
securities of the entity resulting from such transaction (including, without
limitation, an entity which as a result of such transaction owns the Company or
all or substantially all of the Company’s assets either directly or through one
or more subsidiaries), (y) no Organization (excluding any entity resulting from
such transaction or any Benefit Plan of the Company or such entity

 

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resulting from such transaction) beneficially owns, directly or indirectly, 50%
or more of the combined voting power of the then outstanding voting securities
of such entity and (z) at least a majority of the members of the board of
directors or similar board of the entity resulting from such transaction were
members of the Incumbent Board at the time of the execution of the initial
agreement, or of the action of the Board, providing for such transaction; or
(D) approval by the stockholders of the Company of a complete liquidation or
dissolution of the Company. For purposes of the foregoing: “Benefit Plan” means
any employee benefit plan, including any related trust; “Board” means the Board
of Directors of the Company; “Exchange Act” means the Securities Exchange Act of
1934, as amended; and “Organization” means any individual, entity or group
(within the meaning of Section 13(d)(3) or Section 14(d)(2) of the Exchange
Act).

(h) Effect of Failure to Renew by Company. In the event the Company chooses not
to renew the Term hereof, such failure to renew shall be treated as a
termination by the Company other than for “Cause” unless the Company gives
notice that the failure to renew is for “Cause” as defined in Section 5(c).

(i) To the extent any payment under Section 5 shall be required to be delayed
following separation from service to comply with the “specified employee” rules
of Section 409A of the Internal Revenue Code, it shall be delayed (but not more
than is required to comply with such rules).

6. Effect of Termination. The provisions of this Section 6 shall apply to
termination due to the expiration of the Term hereof, termination pursuant to
Section 5 or otherwise.

(a) Payment(s) by the Company and contributions to the cost of the Executive’s
continued participation in the Company’s group health and dental plans that may
be due to the Executive under Section 5 shall constitute the entire obligation
of the Company to the Executive. In order to receive any payments or any other
benefits under Section 5(d) or 5(e) or 5(g) or 5(h), the Executive must first
execute a General Release of Claims in a form acceptable to the Company.

(b) Except for medical and dental insurance coverage continued pursuant to
Section 5(d) or 5(e) or 5(g) or 5(h) hereof, benefits shall terminate pursuant
to the terms of the applicable benefit plans based on the date of termination of
the Executive’s employment without regard to any continuation of Base Salary or
other payment to the Executive following such date of termination.

(c) Provisions of this Agreement shall survive any termination if so provided
herein or if necessary or desirable fully to accomplish the purposes of such
provision, including without limitation the obligations of the Executive under
Sections 7, 8 and 9 hereof. The obligation of the Company to make payments to or
on behalf of the Executive under Section 5(d) or 5(e) or 5(g) or 5(h) hereof is
expressly conditioned upon the Executive’s continued full performance of
obligations under Sections 7, 8 and 9 hereof. The Executive recognizes that,
except as expressly provided in Section 5(d) or 5(e) or 5(g) or 5(h), no
compensation is earned by, or in any way owing to, Executive after termination
of employment.

 

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(d) Any lump-sum payments to be made to the Executive hereunder shall be made as
soon as administratively practicable and in any event no later than 2 1/2 months
after the end of the year in which the Executive becomes entitled to such
payment.

(e) To the extent any payment hereunder shall be required to be delayed until
six months following separation from service to comply with the “specified
employee” rules of Section 409A of the Internal Revenue Code, it shall be
delayed (but not more than is required) to comply with such rules, and shall
promptly after such delay be paid with interest at a reasonable market rate as
determined by the Company

7. Confidential Information.

(a) The Executive acknowledges that the Company and its Affiliates continually
develop Confidential Information, that the Executive may develop Confidential
Information for the Company or its Affiliates and that the Executive may learn
of Confidential Information during the course of employment. The Executive will
comply with the policies and procedures of the Company and its Affiliates for
protecting Confidential Information and shall never disclose to any Person or to
any governmental agency or political subdivision of any government (except as
required by applicable law or for the proper performance of his/her duties and
responsibilities to the Company and its Affiliates), or use for his/her own
benefit or gain, any Confidential Information obtained by the Executive incident
to his/her employment or other association with the Company or any of its
Affiliates. The Executive understands that the restriction shall continue to
apply after his/her employment terminates, regardless of the reason for such
termination.

(b) All documents, records, tapes and other media of every kind and description
relating to the business, present or otherwise, of the Company or its Affiliates
and any copies, in whole or in part, thereof (the “Documents”), whether or not
prepared by the Executive, shall be the sole and exclusive property of the
Company and its Affiliates. The Executive shall safeguard all Documents and
shall surrender to the Company at the time his/her employment terminates, or at
such earlier time or times as the Board or its designee may specify, all
Documents then in the Executive’s possession or control.

(c) The Executive acknowledges and agrees that all Confidential Information and
proprietary materials that are provided by the Company to the Executive under
this Agreement are and shall remain the exclusive property of the Company or the
third party entrusting such Confidential Information or proprietary materials to
the Company.

8. Restricted Activities. The Executive agrees that some restrictions on his/her
activities during and after his/her employment are necessary to protect the
goodwill, Confidential Information and other legitimate interests of the Company
and its Affiliates:

(a) While the Executive is employed by the Company and for the greater of
(i) twelve (12) months after his/her employment terminates or (ii) the period
during which the Executive is receiving payments under Section 5(d) or 5(e) or
5(g) or 5(h) (the “Non-Competition Period”), the Executive shall not, directly
or indirectly, whether as owner, partner,

 

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investor, consultant, agent, employee, co-venturer or otherwise, compete with
the Company or any of its Affiliates or undertake any planning for any business
competitive with the Company or any of its Affiliates. Specifically, but without
limiting the foregoing, the Executive agrees not to engage in any manner in any
activity that is directly or indirectly competitive with the business of the
Company or any of its Affiliates as conducted or under consideration at any time
during the Executive’s employment. Restricted activity includes without
limitation accepting employment or a consulting position with any Person who is,
or at any time within twelve (12) months prior to the termination of the
Executive’s employment has been, a competitor or a customer of the Company or
any of its Affiliates. For the purposes of this Section 8, the business of the
Company and its Affiliates shall include all Products and the Executive’s
undertaking shall encompass all items, products and services that may be used in
substitution for Products. The foregoing shall not prohibit the Executive’s
passive ownership of two percent (2%) or less of the equity securities of any
publicly traded company.

(b) The Executive agrees that, during his/her employment with the Company or any
Affiliate of the Company, he/she will not undertake any outside activity,
whether or not competitive with the business of the Company or its Affiliates,
that could reasonably give rise to a conflict of interest or otherwise interfere
with his/her duties and obligations to the Company or any of its Affiliates.

(c) The Executive further agrees that while he/she is employed by the Company or
any Affiliate of the Company and thereafter during the Non-Competition Period,
the Executive will not hire or attempt to hire any employee of the Company or
any of its Affiliates, assist in such hiring by any Person, encourage any such
employee to terminate his/her or her relationship with the Company or any of its
Affiliates or solicit or encourage any customer or vendor of the Company or any
of its Affiliates to terminate its relationship with them, or, in the case of a
customer, to conduct with any Person any business or activity which such
customer conducts or could conduct with the Company or any of its Affiliates.

9. Assignment of Rights to Intellectual Property. The Executive shall promptly
and fully disclose, if he/she has not done so already, all Intellectual Property
to the Company. The Executive shall maintain adequate records (whether written,
electronic, or otherwise) to document the Intellectual Property, including
without limitation the conception and reduction to practice of all inventions,
and shall make such records available to the Company upon request. The Company
shall have sole ownership of all Intellectual Property and all such records with
respect thereto. The Executive hereby assigns, conveys, and grants to the
Company (or as otherwise directed by the Company), and agrees to assign, convey
and grant to the Company (or as otherwise directed by the Company), all of
his/her right, title, and interest in and to the Intellectual Property and any
and all patents, patent applications, and copyrights relating to the
Intellectual Property. The Executive agrees to execute any and all applications
for domestic and foreign patents, copyrights or other proprietary rights and to
do such other acts (including without limitation the execution and delivery of
instruments of further assurance or confirmation) requested by the Company to
assign the Intellectual Property to the Company and to permit the Company to
enforce any patents, copyrights or other proprietary rights to the Intellectual
Property. The Executive will not charge the Company for time spent in complying
with these obligations. All copyrightable works that the Executive creates shall
be considered “work made for hire”.

 

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The Executive represents that the attached Exhibit A contains a complete list of
all inventions, copyrightable works, tangible materials, and other intellectual
property that the Executive (either alone or jointly with others) conceived,
developed, discovered, created, or reduced to practice prior to the Effective
Date (the “Prior IP”). The Prior IP is not assigned to the Company under this
Agreement, except to the extent that the Executive expressly assigns such Prior
IP to the Company under the terms of a separate written instrument. If no Prior
IP is listed on Exhibit A, the Executive represents that no Prior IP exists. The
Executive recognizes that the protection of the Intellectual Property of the
Company against unauthorized disclosure and use is of critical importance to the
Company, and therefore, the Executive agrees to use his/her best efforts and
exercise utmost diligence to protect and safeguard the Intellectual Property of
the Company and its Affiliates, if any, and, except as may be expressly required
by the Company in connection with the Executive’s performance of his/her
obligations to the Company under this Agreement, the Executive shall not, either
during the Term of this Agreement or thereafter, directly or indirectly, use for
his/her own benefit or for the benefit of another, or disclose to another, any
of such Intellectual Property.

10. Notification Requirement. Until the conclusion of the Non-Competition Period
the Executive shall give notice to the Company of each new business activity
he/she plans to undertake, at least twenty-one (21) days prior to beginning any
such activity. Such notice shall state the name and address of the Person for
whom such activity is undertaken and the nature of the Executive’s business
relationship(s) and position(s) with such Person. The Executive shall provide
the Company with such other pertinent information concerning such business
activity as the Company may reasonably request in order to determine the
Executive’s continued compliance with his/her obligations under Sections 7, 8
and 9 hereof.

11. Enforcement of Covenants. The Executive acknowledges that he/she has
carefully read and considered all the terms and conditions of this Agreement,
including the restraints imposed upon him/her pursuant to Sections 7 and 8
hereof. The Executive agrees that said restraints are necessary for the
reasonable and proper protection of the Company and its Affiliates and that each
and every one of the restraints is reasonable in respect to subject matter,
length of time and geographic area. The Executive further acknowledges that,
were he/she to breach any of the covenants contained in Sections 7 or 8 hereof,
the damage to the Company would be irreparable. The Executive therefore agrees
that the Company, in addition to any other remedies available to it, shall be
entitled to preliminary and permanent injunctive relief against any breach or
threatened breach by the Executive of any of said covenants, without having to
post bond. The parties further agree that, in the event that any provision of
Section 7 or 8 hereof shall be determined by any court of competent jurisdiction
to be unenforceable by reason of its being extended over too great a time, too
large a geographic area or too great a range of activities, such provision shall
be deemed to be modified to permit its enforcement to the maximum extent
permitted by law.

12. Conflicting Agreements. The Executive hereby represents and warrants that
the

 

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execution of this Agreement and the performance of his/her obligations hereunder
will not breach or be in conflict with any other agreement to which the
Executive is a party or is bound and that the Executive is not now subject to
any covenants against competition or similar covenants that would affect the
performance of his/her obligations hereunder. The Executive will not disclose to
or use on behalf of the Company any proprietary information of a third party
without such party’s consent.

13. Indemnification. The Company shall indemnify the Executive to the extent
provided in its then current Articles or By-Laws. The Executive agrees to
promptly notify the Company of any actual or threatened claim arising out of or
as a result of his/her employment with the Company.

14. Definitions. For purposes of this Agreement, the following definitions
apply:

(a) “Affiliates” means all persons and entities directly or indirectly
controlling, controlled by or under common control with the Company, where
control may be by either management authority or equity interest.

(b) “Confidential Information” means any and all information of the Company and
its Affiliates that is not generally known by others. Confidential Information
includes without limitation such information relating to (i) the development,
research, testing, manufacturing, marketing and financial activities of the
Company and its Affiliates, (ii) the Products, (iii) the costs, sources of
supply, financial performance and strategic plans of the Company and its
Affiliates, (iv) the identity and special needs of the customers of the Company
and its Affiliates and (v) the people and organizations with whom the Company
and its Affiliates have business relationships and those relationships.
Confidential Information also includes comparable information that the Company
or any of its Affiliates have received belonging to others or which was received
by the Company or any of its Affiliates with any understanding that it would not
be disclosed.

(c) “Good Reason” means: (i) the relocation of the Executive’s principal office,
without his/her prior consent, to a location more than thirty (30) miles from
its location on the day prior to the Change in Control; (ii) failure of the
Company to continue the Executive in the position held immediately prior to the
Change of Control; or (iii) material and substantial diminution in the nature or
scope of the Executive’s responsibilities, duties or authority; however, the
Company’s failure to continue the Executive’s appointment or election as a
director or officer of any of its Affiliates and any diminution of the business
of the Company or any of its Affiliates, including without limitation the sale
or transfer of any or all of the assets of the Company or any of its Affiliates,
shall not constitute “Good Reason”.

(d) “Intellectual Property” means inventions, discoveries, developments,
methods, processes, compositions, works, concepts and ideas (whether or not
patentable or copyrightable or constituting trade secrets) conceived, made,
created, developed or reduced to practice by the Executive (whether alone or
with others, whether or not during normal business hours or on or off Company
premises) during the Executive’s employment and during the period of twelve
(12) months immediately following termination of his/her employment that relate
to either the Products or any prospective activity of the Company or any of its
Affiliates.

 

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(e) “Person” means an individual, a corporation, an association, a partnership,
an estate, a trust and any other entity or organization, other than the Company
or any of its Affiliates.

(f) “Products” mean all products planned, researched, developed, under
development, tested, manufactured, sold, licensed, leased or otherwise
distributed or put into use by the Company or any of its Affiliates, together
with all services provided or planned by the Company or any of its Affiliates,
during the Executive’s employment.

15. Withholding. All payments made by the Company under this Agreement shall be
reduced by any tax or other amounts required to be withheld by the Company under
applicable law.

16. Assignment. Neither the Company nor the Executive may make any assignment of
this Agreement or any interest herein, by operation of law or otherwise, without
the prior written consent of the other; provided, however, that the Company may
assign its rights and obligations under this Agreement without the consent of
the Executive in the event that the Company shall hereafter affect a
reorganization, consolidate with, or merge into, any other Person or transfer
all or substantially all of its properties or assets to any other Person. This
Agreement shall inure to the benefit of and be binding upon the Company and the
Executive, their respective successors, executors, administrators, heirs and
permitted assigns.

17. Severability. If any portion or provision of this Agreement shall to any
extent be declared illegal or unenforceable by a court of competent
jurisdiction, then the remainder of this Agreement, or the application of such
portion or provision in circumstances other than those as to which it is so
declared illegal or unenforceable, shall not be affected thereby, and each
portion and provision of this Agreement shall be valid and enforceable to the
fullest extent permitted by law.

18. Waiver. No waiver of any provision hereof shall be effective unless made in
writing and signed by the waiving party. The failure of either party to require
the performance of any term or obligation of this Agreement, or the waiver by
either party of any breach of this Agreement, shall not prevent any subsequent
enforcement of such term or obligation or be deemed a waiver of any subsequent
breach.

19. Notices. Any and all notices, requests, demands and other communications
provided for by this Agreement shall be in writing and shall be effective when
delivered in person or deposited in the United States mail, postage prepaid,
registered or certified, and addressed to the Executive at his/her last known
personal address on the books of the Company or, in the case of the Company, at
its principal place of business, attention of Senior Attorney, or to such other
address as either party may specify by notice to the other actually received.

20. Entire Agreement. This Agreement constitutes the entire agreement between
the parties and supersedes all prior communications, agreements and
understandings, written or oral, with respect to the terms and conditions of the
Executive’s employment, excluding any obligations with respect to the securities
of the Company or the grant of any stock options.

 

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21. Amendment. This Agreement may be amended or modified only by a written
instrument signed by the Executive and by an expressly authorized representative
of the Company.

22. Headings. The headings and captions in this Agreement are for convenience
only and in no way define or describe the scope or content of any provision of
this Agreement.

23. Counterparts. This Agreement may be executed in two or more counterparts,
each of which shall be an original and all of which together shall constitute
one and the same instrument.

24. Governing Law. This is a contract and shall be construed and enforced under
and be governed in all respects by the laws of the Commonwealth of
Massachusetts, without regard to the conflict of laws principles thereof.

[SIGNATURE PAGE FOLLOWS]

 

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IN WITNESS WHEREOF, this Agreement has been executed as a sealed instrument by
the Company, by its duly authorized representative, and by the Executive, as of
the date first above written.

 

THE EXECUTIVE:     ANTIGENICS INC., a Delaware corporation

/s/ Karen Higgins Valentine

    By:  

/s/ Garo H. Armen

Karen Higgins Valentine     Name:   Garo H. Armen     Title:   Chairman & CEO

 

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EXHIBIT A

LIST OF PRIOR IP

 

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