Exhibit 10.40

ANTIGENICS INC.

SECURITIES REPURCHASE AGREEMENT

This Securities Repurchase Agreement (this “Agreement”) is made as of
December 7, 2010 (the “Effective Date”) by and between ANTIGENICS INC., a
Delaware corporation (the “Company”), and INGALLS & SNYDER VALUE PARTNERS L.P.
(the “Bond Holder”).

RECITALS

WHEREAS, the Bond Holder desires to sell, and the Company desires to repurchase,
an aggregate of $8,048,000 in principal amount of the Company’s 5.25%
convertible senior notes due February 2025 (collectively, the “Bonds”) in
exchange for an aggregate cash payment of $6,374,337.24 (the “Purchase Price”)
and to cancel the Bonds upon the terms and conditions set forth herein.

AGREEMENT

1. Sale of Bonds. The Bond Holder hereby agrees to assign, sell and transfer the
Bonds, plus all claims arising out of or relating to the Bonds, including but
not limited to any accrued but unpaid interest, to the Company in exchange for
the Purchase Price. Subject to the approval of the Company’s Board of Directors,
on December 9, 2010, or such other date or time as mutually agreed upon by the
Parties (the “Closing”), the Bond Holder shall deliver to the Company the Bonds,
duly endorsed or accompanied by an assignment duly endorsed, against payment of
the Purchase Price, by wire transfer to the Bond Holder. At the Closing, upon
receipt by the Bond Holder of the Purchase Price, the Company shall become the
legal and beneficial owner of the Bonds and of all rights and interest therein
or related thereto and to the monies due and to become due under the terms of
the Bonds. The Bond Holder hereby agrees that upon receipt of the Purchase
Price, the Bonds shall be cancelled and the Company shall have no further
obligation to the Bond Holder thereunder.

2. Representations and Warranties of the Company. The Company hereby represents
and warrants to the Bond Holder that as of the Effective Date:

2.1 Organization. The Company is duly incorporated and validly existing in good
standing under the laws of the State of Delaware. The Company has full corporate
power and authority to own, operate and occupy its properties and to conduct its
business as presently conducted and is registered or qualified to do business
and is in good standing in each jurisdiction in which it owns or leases property
or transacts business and where the failure to be so qualified would have a
material adverse effect on the Company, and, to the Company’s knowledge, no
proceeding has been instituted in any such jurisdiction revoking, limiting or
curtailing, or seeking to revoke, limit or curtail, such power and authority or
qualification.

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2.2 Due Authorization. Subject to approval by the Company’s Board of Directors,
the Company has all requisite corporate power and authority to execute, deliver
and perform its obligations under this Agreement. Subject to approval by the
Company’s Board of Directors, this Agreement has been duly authorized and
validly executed and delivered by the Company and no other corporate action on
the part of the Company or its stockholders is necessary to authorize the
execution and delivery by the Company of this Agreement or the consummation of
the transactions contemplated by this Agreement. This Agreement, assuming due
and valid authorization, execution and delivery hereof and thereof by the Bond
Holder, constitutes a legal, valid and binding agreement of the Company,
enforceable against the Company in accordance with its terms, except as rights
to indemnity and contribution may be limited by state or federal securities
laws, except as enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium or similar laws affecting creditors’ and
contracting parties’ rights generally, and except as enforceability may be
subject to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law).

2.3 Non-Contravention. The execution and delivery of this Agreement and the
consummation of the transactions contemplated hereby and thereby will not
(a) conflict with or constitute a material violation of or default (with the
passage of time or otherwise) under or give rise to any right of termination,
material amendment, cancellation or acceleration or loss of any material rights
under (i) any material contracts to which the Company is a party, or (ii) the
certificate of incorporation or the bylaws of the Company or any similar
organizational document of the Company, or (b) (i) result in the creation or
imposition (or the obligation to create or impose) of any material lien,
encumbrance, claim, security interest, pledge, charge or restriction of any kind
upon any of the properties or assets of the Company or (ii) an acceleration of
indebtedness pursuant to any obligation, agreement or condition contained in
agreement or document to which the Company is a party or is bound other than the
with respect to the Bonds, or (c) to the Company’s knowledge, violate any order
or decree applicable to the Company, or by which it or any of its operations are
bound, and no such violation or default currently exists. No consent, approval,
authorization or other order of, or registration, qualification or filing with,
any regulatory body, administrative agency or other governmental body in the
United States is required for the execution and delivery of the Agreement prior
to the Effective Date except for any securities filings required to be made
under state securities laws.

2.4 Exchange Act Compliance. The documents that the Company filed under the
Securities Exchange Act of 1934 (the “Exchange Act”) since December 31, 2009
(including all exhibits included therein and documents incorporated by reference
therein hereinafter being referred to as the “Required Documents”) complied in
all material respects with the requirements of the Exchange Act, and the rules
and regulations of the Commission promulgated thereunder as of their respective
filing dates, and none of the Required Documents, when filed, contained any
untrue statement of a material fact or. omitted to state a material fact
required to be stated therein or necessary in order to make the statements
therein, in light of the circumstances under which they were made, not
misleading.

 

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2.5 Non-Public Information. The Bond Holder has not requested from the Company,
and the Company has not furnished to the Bond Holder, any material non-public
information concerning the Company.

2.6 No Reliance. In entering into this Agreement, the Company (i) is not relying
on any advice or representation of the Bond Holder or any of its affiliates
(other than the representations of the Bond Holder contained herein), (ii) has
not received from the Bond Holder or any of its affiliates any assurance or
guarantee as to the merits (whether legal, regulatory, tax, financial or
otherwise) of entering into this Agreement, (iii) has consulted with its own
legal, regulatory, tax, business, investment, financial and accounting advisors
to the extent that it has deemed necessary, and (iv) has entered into this
Agreement based on its own independent judgment and on the advice of its
advisors as it has deemed necessary, and not on any view (whether written or
oral) expressed by the Bond Holder or any of its affiliates. Neither the Bond
Holder nor any of its affiliates is now or has ever been a financial advisor, or
other fiduciary, with respect to the Company.

2.7 Bankruptcy Protection. The Company has not taken any steps, and does not
currently expect to take any steps, to seek protection pursuant to 11 U.S.C. §§
101 et seq. (the “Bankruptcy Code”) or any similar state bankruptcy law nor does
the Company have any knowledge or reason to believe that its creditors intend to
initiate an involuntary proceeding under the Bankruptcy Code or any such state
law.

2.8 No Broker. No broker, finder or other person acting under the authority of
the Company is entitled to any broker’s commission or other fee in connection
with the transfer of the Bonds for which the Company would be responsible, in
whole or in part.

3. Representations and Warranties of the Bond Holder. The Bond Holder hereby
represents and warrants to the Company as follows:

3.1 Due Authorization. The Bond Holder has all requisite corporate power and
authority to execute, deliver and perform its obligations under this Agreement,
and this Agreement has been duly authorized and validly executed and delivered
by the Bond Holder and no other corporate action on the part of the Bond Holder
is necessary to authorize the execution and delivery by the Bond Holder of this
Agreement. This Agreement constitutes a legal, valid and binding agreement of
the Bond Holder, enforceable against the Bond Holder in accordance with its
terms, except as enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium or similar laws affecting creditors’ and
contracting parties’ rights generally, and except as enforceability may be
subject to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law).

3.2 Ownership of Bonds. The Bond Holder has, and at the Closing will have, good
and valid right, title and interest (legal and beneficial) in and to the Bonds,
free and clear of all liens, pledges, security interests, charges, contractual
obligations, claims or encumbrances of any kind. Upon payment for the Bonds in
accordance with this Agreement, the Bond Holder will convey the Bonds to the
Company free and clear of all liens, pledges, security interests charges,
contractual obligations, claims or encumbrances of any kind.

 

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3.3 No Legal, Tax or Investment Advice. The Bond Holder understands that nothing
in this Agreement or any other materials presented to the Bond Holder in
connection with the Agreement constitutes legal, tax or investment advice and
represents and warrants to the Company that it has consulted such legal, tax and
investment advisors as it, in its sole discretion, has deemed necessary or
appropriate.

3.4 Affiliate Status. As of Effective Date, the Bond Holder represents and
warrants that the Bond Holder is not an affiliate of the Company, and has not
been an affiliate of the Company for the three months preceding the Effective
Date.

3.5 No Broker. No broker, finder or other person acting under the authority of
the Bond Holder is entitled to any broker’s commission or other fee in
connection with the transfer of the Bonds for which the Bond Holder would be
responsible, in whole or in part.

4. Amendment and Waiver. No provision of this Agreement may be amended or
modified except upon the written consent of the Company and the Bond Holder, and
no provision hereof may be waived other than by a written instrument signed by
the party against whom enforcement of any such waiver is sought.

5. Miscellaneous.

5.1 Attorneys’ Fees. In the event that any suit or action is instituted under or
in relation to this Agreement, including, without limitation to enforce any
provision in this Agreement, each party in such dispute shall pay all of its own
fees, costs and expenses of enforcing any right of such party under or with
respect to this Agreement, including without limitation, such fees and expenses
of attorneys and accountants, which shall include, without limitation, all fees,
costs and expenses of appeals.

5.2 Headings; Construction. The headings of the various sections of this
Agreement have been inserted for convenience of reference only and shall not be
deemed to be part of this Agreement. The language used in this Agreement is and
will be deemed to be the language chosen by the parties to express their mutual
intent, and no rules of strict construction will be applied against any party.

5.3 Pronouns. All pronouns contained herein, and any variations thereof, shall
be deemed to refer to the masculine, feminine or neutral, singular or plural, as
to the identity of the parties hereto may require.

5.4 Severability. In case any provision contained in this Agreement should be
invalid, illegal or unenforceable in any respect, the validity, legality and
enforceability of the remaining provisions contained herein shall not in any way
be affected or impaired thereby.

5.5 Governing Law. This Agreement shall be governed by, and construed in
accordance with, the internal laws of the State of New York, without giving
effect to the principles of conflicts of law. The parties agree that any action
brought by either party

 

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under or in relation to this Agreement, including without limitation to
interpret or enforce any provision of this Agreement, shall be brought in, and
each party agrees to and does hereby submit to the jurisdiction and venue of,
any state or federal court located in New York.

5.6 Entire Agreement. This Agreement constitutes the full and entire
understanding and agreement between the parties with regard to the subjects
hereof, and no party shall be liable or bound to any other in any manner by any
oral or written representations, warranties, covenants and agreements except as
specifically set forth herein. Each party expressly represents and warrants that
it is not relying on any oral or written representations, warranties, covenants
or agreements outside of this Agreement.

5.7 Counterparts. This Agreement may be executed in two (2) or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one (1) instrument, and shall become
effective when one (1) or more counterparts have been signed by each party
hereto and delivered to the other parties.

5.8 Successors and Assigns. This Agreement shall be binding upon and inure to
the benefit of the parties and their respective successors and assigns.

5.9 No Third Party Beneficiaries. This Agreement is intended for the benefit of
the parties hereto and their respective permitted successors and assignees, and
is not for the benefit of, nor may any provision hereof be enforced by, any
other person.

5.10 Further Assurances. Each party shall do and perform, or cause to be done
and performed, all such further acts and things, and shall execute and deliver
all such other agreements, certificates, instruments and documents, as any other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

 

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IN WITNESS WHEREOF, the parties hereto have executed this SECURITIES REPURCHASE
AGREEMENT as of the date set forth in the first paragraph hereof.

 

COMPANY:     BOND HOLDER: ANTIGENICS INC.     INGALLS & SNYDER VALUE PARTNERS
L.P. By:  

/s/ Shalini Sharp

    By:  

/s/ Thomas O. Boucher Jr.

Name:  

SHALINI SHARP

    Name:  

Thomas O. Boucher Jr.

Title:  

CFO

    Title:  

GENERAL PARTNER