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EXHIBIT 5.1
[PALMER & DODGE LETTERHEAD]
August 14, 2000
Dyax Corp.
One Kendall Square
Building 600
Cambridge, Massachusetts 02139
We are rendering this opinion in connection with the Registration
Statement (the "Registration Statement") on Form S-1 (Commission File No.
333-37394) of Dyax Corp. (the "Company") filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, on or about the date
hereof. The Registration Statement relates to up to 4,000,000 shares (4,600,000
shares if the underwriters' over-allotment option is exercised in full) of the
Company's Common Stock, $0.01 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. We are familiar with the proceedings of the Board of
Directors on March 16, 2000 and May 10, 2000 in connection with the
authorization, issuance and sale of the Shares. We have examined such other
documents as we consider necessary to render this opinion.
Based upon the foregoing, we are of the opinion that the Shares have
been duly authorized and, when issued and delivered by the Company against
payment therefor at the price to be determined pursuant to the Resolutions, will
be validly issued, fully paid and non-assessable.
We hereby consent to the filing of this opinion as a part of 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
PALMER & DODGE LLP
