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EXHIBIT 5.1
[PILLSBURY MADISON & SUTRO LLP LETTERHEAD]
November 15, 2000
IDEC Pharmaceuticals Corporation
3030 Callan Road
San Diego, California 92121
Re: IDEC Pharmaceuticals Corporation Registration Statement on
Form S-3 for Sale of 2,990,000 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 registration for sale of
2,600,000 shares (2,990,000 shares including the underwriters over-allotment
option) of common stock (the "Shares") pursuant to the U.S. Purchase Agreement
by and among the Company and Merrill Lynch, Pierce, Fenner & Smith Incorporated,
Salomon Smith Barney, Inc., and Banc of America Securities LLC, and the
International Purchase Agreement by and among the Company, Merrill Lynch
International, Salomon Brothers International Limited and Bank of America
International Limited (collectively, the "Purchase Agreements"). The Shares are
to be sold in accordance with the Purchase Agreements, as described in the
Company's Registration Statement on Form S-3 ("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 601(b)(5)(i) of Regulation S-B.
We have reviewed the Company's charter documents, the corporate proceedings
taken by the Company in connection with the original issuance of the Shares, and
a certificate of a Company officer regarding (among other things) the Company's
receipt of consideration upon the original issuance of the Shares. Based on such
review, we are of the opinion that the Shares are duly authorized, validly
issued, fully paid and nonassessable.
We consent to the filing of this opinion 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
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November 15, 2000
Page 2
regulations of the Securities and Exchange Commission promulgated thereunder, or
Item 509 of Regulation S-B.
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/ PILLSBURY MADISON & SUTRO LLP
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