EXHIBIT 5.1
February 23, 1998
IDEC Pharmaceuticals Corporation
11011 Torreyana Road
San Diego, CA 92121
Re: IDEC PHARMACEUTICALS CORPORATION
REGISTRATION STATEMENT ON FORM S-3 FOR 2,300,000
SHARES OF COMMON STOCK
Ladies and Gentlemen:
We have acted as counsel to IDEC Pharmaceuticals Corporation,
a Delaware corporation (the "Company"), in connection with the proposed issuance
and sale by the Company of up to Two Million Three Hundred Thousand (2,300,000)
shares of the Company's Common Stock (the "Shares") pursuant to the Company's
Registration Statement on Form S-3 (the "Registration Statement") filed with the
Securities and Exchange Commission under the Securities Act of 1933, as amended
(the "Act").
This opinion is being furnished in accordance with the
requirements of Item 16 of Form S-3 and Item 6-1(b)(5)(i) of Regulation S-K.
We have examined originals or copies of (i) the Amended and
Restated Certificate of Incorporation of the Company; (ii) the Bylaws of the
Company; (iii) certain resolutions of the Board of Directors of the Company; and
(v) such other documents and records as we have deemed necessary and relevant
for the purposes hereof. In addition, we have relied on certificates of officers
of the Company and certificates of public officials as to certain matters of
fact relating to this opinion and have made such investigations of law as we
have deemed necessary and relevant as a basis hereof.
We have assumed the genuineness of all signatures, the
authenticity of all documents, certificates and records submitted to us as
originals, the conformity to authentic original documents, certificates and
records of all such documentation submitted to us as copies and the truthfulness
of all statements of facts contained therein. Based on the foregoing and subject
to the limitations set forth herein and having due regard for such legal
considerations as we deem relevant, we are of the opinion that the Shares, when
issued and sold in the manner described in the Registration Statement, will be
validly issued, fully paid and nonassessable shares of the Common Stock.
IDEC Pharmaceuticals Corporation February 23, 1998
Page 2
We consent to the filing of this opinion letter as Exhibit 5.1
to the Registration Statement and to the reference to this firm under the
caption "Legal Matters" in the prospectus which is part of the Registration
Statement. In giving this consent, we do not thereby admit that we are within
the category of persons whose consent is required under Section 7 of the Act,
the rules and regulations of the Securities and Exchange Commission promulgated
thereunder, or Item 509 of Regulation S-K.
The foregoing opinion is based on and limited to the General
Corporation Law of the State of Delaware and the relevant federal laws of the
United States, and we express no opinion with respect to the laws of any other
jurisdiction.
This opinion letter is rendered as of the date first written
above and we disclaim any obligation to advise you of facts, circumstances,
events or developments which hereafter may be brought to our attention and which
may alter, affect or modify the opinion expressed herein. Our opinion is
expressly limited to the matters set forth above and we render no opinion,
whether by implication or otherwise, as to any other matters relating to the
Company or the Shares.
Very truly yours,
/s/ Brobeck, Phleger & Harrison LLP
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BROBECK, PHLEGER & HARRISON LLP