Amendment No. 1 to License Agreement between University of Miami and Seattle Genetics, Inc.

Exhibit 10.16
Confidential treatment requested

AMENDMENT NO. 1 TO LICENSE AGREEMENT
BETWEEN
UNIVERSITY OF MIAMI
AND
SEATTLE GENETICS, INC.

    This Amendment No. 1 to License Agreement (the "Amendment") is made as of August 4, 2000 by and between University of Miami and its School of Medicine, whose principal place of business is at 1600 N.W. 10^th Avenue, Miami, Florida 33136 ("Licensor"), and Seattle Genetics, Inc., a Delaware corporation having offices at 22215 26th Avenue SE, Bothell, WA 98021 ("Licensee").

    WHEREAS, Licensor and Licensee are parties to that certain License Agreement dated September 20, 1999 (the "Agreement")

    WHEREAS, Licensor and Licensee wish to amend the Agreement as set forth in this Amendment;

    NOW THEREFORE, for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties agree as follows:

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Section 8.1(d) is deleted in its entirety and replaced with the following:



"(d)

Running Royalty in an amount equal to (i) [*] percent ([*]%) of the Net Sales of the Non-Conjugated Products and Conjugated Products and (ii) [*] percent ([*]%) on the Net Sales of the Non-Conjugated Products and Conjugated Products equal to or exceeding [*] dollars ($[*]) for the years [*] through [*] (years [*]) of this Agreement; provided, that, if royalties are paid pursuant to (ii) above, (i) shall not apply.

    The Parties, intending to be legally bound, have caused this Amendment to be executed by their authorized representatives on the dates set forth below.

[*]   Confidential treatment requested

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