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May 16, 1996
VIA EDGAR
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
RE: SUGEN, INC. - REGISTRATION STATEMENT ON FORM S-3 (NO. 333-2304)
Ladies and Gentlemen:
Pursuant to Rule 477 and Rule 478 of the Securities Act of 1933, as amended,
SUGEN, Inc. hereby requests the immediate withdrawal of its Registration
Statement on Form S-3, No. 333-2304, which was filed with the Securities and
Exchange Commission on March 12, 1996, as amended on April 15, 1996 (the
"Registrant Statement"). None of the securities to be registered by the
Company pursuant to the Registration Statement have been issued or sold.
SUGEN, INC.
By: /s/ James L. Tyree
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James L. Tyree, President
