Seattle Genetics Inc (SGEN): Baker Bros. Keeps Buying Shares

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Page 13 of 15 SEC Filing

(d) Certain securities of the Issuer are held directly
by 667, a limited partnership the sole general partner of which is Baker Biotech Capital, L.P., a limited partnership the sole
general partner of which is Baker Biotech Capital (GP), LLC. Julian C. Baker and Felix J. Baker are the controlling members of
Baker Biotech Capital (GP), LLC.

Certain securities of the Issuer are held directly by Life Sciences,
a limited partnership the sole general partner of which is Baker Brothers Life Sciences Capital, L.P., a limited partnership the
sole general partner of which is Baker Brothers Life Sciences Capital (GP), LLC. Julian C. Baker and Felix J. Baker are the controlling
members of Baker Brothers Life Sciences Capital (GP), LLC.

(e) Not applicable.

 

ITEM 6. Contracts, Arrangements, Understandings or Relationships
With Respect to Securities of the Issuer.

 

The disclosure in Item 4 is incorporated
by reference herein.

The Loan Agreement and the Proceeds Agreement are filed as Exhibits
99.1 and 99.2, respectively, and are incorporated by reference herein.

 

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