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PALMER & DODGE LLP
One Beacon Street, Boston, MA 02108-3190
EXHIBIT 5.1
TELEPHONE: (617) 573-0100 FACSIMILE: (617) 227-4420
September 19, 2000
Antigenics Inc.
630 Fifth Avenue, Suite 2100
New York, New York 10111
We are rendering this opinion in connection with the Registration
Statement on Form S-4 (the "Registration Statement") filed by Antigenics Inc.
(the "Company") with the Securities and Exchange Commission under the Securities
Act of 1933, as amended (the "Securities Act"), on or about the date hereof. The
Registration Statement relates to up to 2,898,405 shares (the "Merger Shares")
of the Company's common stock, $0.01 par value per share, to be issued in
connection with the merger of Aquila Biopharmaceuticals, Inc. ("Aquila") with
and into a wholly owned subsidiary of the Company, pursuant to the Agreement and
Plan of Merger dated as of August 18, 2000 (the "Agreement") among the Company,
such subsidiary and Aquila. We understand that the Merger Shares are to be
offered and sold in the manner described in the Registration Statement.
We have acted as your counsel in connection with the preparation of the
Registration Statement and are familiar with the proceedings taken by the
Company in connection with the authorization and issuance of the Merger Shares.
We have examined such documents as we consider necessary to enable us to render
this opinion.
Based upon the foregoing, we are of the opinion that upon issuance in
accordance with the Agreement, the Merger Shares will be duly authorized,
validly issued, fully paid and nonassessable.
The foregoing opinion is limited to Delaware General Corporation Law and
the federal laws of the United States.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption "Legal
Matters" in the prospectus filed as part thereof.
Very truly yours,
/s/ PALMER & DODGE LLP
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PALMER & DODGE LLP
