X0202 3 2004-10-13 0 0001060736 SEATTLE GENETICS INC /WA SGEN 0001307726 Baker Biotech Capital II (Z) (GP), LLC 667 MADISON AVENUE NEW YORK NY 10021 1 0 1 0 0001087939 BAKER JULIAN 667 MADISON AVENUE NEW YORK NY 10021 0 0 1 0 0001087940 BAKER FELIX 667 MADISON AVENUE NEW YORK NY 10021 1 0 1 0 Common Stock 13542 I See Footnote Common Stock Warrants (right to buy) 6.25 2003-07-08 2011-12-31 Common Stock 42981 I See Footnote Series A Convertible Preferred Stock 2.50 2004-07-08 Common Stock 343850 I See Footnote In addition to Baker Biotech Capital II (Z) (GP), LLC, this Form 3 is being filed jointly by Julian C. Baker and Felix J. Baker, each of whom has the same business address as Baker Biotech Capital II (Z) (GP), LLC and may be deemed to have a pecuniary interest in securities owned by it. Felix J. Baker is a director of the Issuer. Because of certain business relationships with other shareholders of the Issuer, the Reporting Persons have filed on Schedule 13D as if they were a member of a group with such shareholders. (continued on footnote(2)) However, the Reporting Persons disclaim that they and any other person or persons, including those persons with whom the Reporting Persons have filed a Schedule 13D, in fact constitute a "group" for purposes of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended, or Rule 13d-5 thereunder, or that they are the beneficial owners of any securities owned by any such other persons, and each of them disclaims beneficial ownership of securities reported herein except to the extent of their pecuniary interest, if any, therein. Represents shares and/or warrants owned directly by Baker Biotech Fund II (Z), L.P., a limited partnership of which the sole general partner is Baker Biotech Capital II (Z), L.P., a limited partnership of which the sole general partner is Baker Biotech Capital II (Z) (GP), LLC. Felix J. Baker and Julian C. Baker are the controlling members of Baker Biotech Capital II (Z) (GP), LLC. None. /s/ Julian C. Baker, as Managing Member of Baker Biotech Capital II (Z) (GP), LLC 2004-11-03 /s/ Julian C. Baker 2004-11-03 /s/ Felix J. Baker 2004-11-03