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[PALMER & DODGE LLP LETTERHEAD]
EXHIBIT 5.1
October 20, 2000
ArQule, Inc.
19 Presidential Way
Woburn, Massachusetts 01801
We are rendering this opinion in connection with the Registration Statement on
Form S-3 (the "Registration Statement") filed by ArQule, 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 2,875,000 shares of the Company's Common Stock, $.01
par value per share (the "Shares"). We understand that the 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, issuance and sale of the Shares.
We have examined all such documents as we consider necessary to enable us to
render this opinion.
Based on the foregoing, we are of the opinion that upon the due issuance and
delivery of the Shares against payment therefor as contemplated by the
Registration Statement, the Shares will be validly issued, fully paid, and
nonassessable.
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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