Sec Form 4 Filing - BAKER FELIX @ SEATTLE GENETICS INC /WA - 2016-11-07

Insider filing report for Changes in Beneficial Ownership
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FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person
BAKER FELIX
2. Issuer Name and Ticker or Trading Symbol
SEATTLE GENETICS INC /WA [ SGEN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
X __ Director X __ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last) (First) (Middle)
667 MADISON AVENUE, 21ST FLOOR
3. Date of Earliest Transaction (MM/DD/YY)
11/07/2016
(Street)
NEW YORK, NY10065
4. If Amendment, Date Original Filed (MM/DD/YY)
6. Individual or Joint/Group Filing (Check Applicable Line)
_____ Form filed by One Reporting Person
__ X __ Form filed by More than One Reporting Person
(City) (State) (Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 107,511 ( 1 ) D
Common Stock 107,504 ( 2 ) D
Common Stock 11/07/2016 P 5,533 A $ 58.7428 ( 3 ) 4,842,742 I See footnote ( 4 ) ( 7 ) ( 8 ) ( 9 )
Common Stock 11/07/2016 P 50,667 A $ 58.7428 ( 3 ) 40,590,914 I See footnote ( 5 ) ( 7 ) ( 8 ) ( 9 )
Common Stock 11/08/2016 P 32,122 A $ 59.4646 ( 6 ) 4,874,864 I See footnote ( 4 ) ( 7 ) ( 8 ) ( 9 )
Common Stock 11/08/2016 P 294,178 A $ 59.4646 ( 6 ) 40,885,092 I See footnote ( 5 ) ( 7 ) ( 8 ) ( 9 )
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(MM/DD/YY)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Reporting Owners
Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
BAKER FELIX
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY10065
X X
BAKER JULIAN
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY10065
X X
Baker Bros. Advisors (GP) LLC
667 MADISION AVENUE, 21ST FLOOR
NEW YORK, NYNew York
X X
BAKER BROS. ADVISORS LP
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY10065
X X
667, L.P.
667 MADISION AVENUE, 21ST FLOOR
NEW YORK, NY10065
X X
Baker Brothers Life Sciences LP
667 MADISION AVENUE, 21ST FLOOR
NEW YORK, NY10065
X X
Signatures
/s/ Felix J. Baker 11/08/2016
Signature of Reporting Person Date
/s/ Julian C. Baker 11/08/2016
Signature of Reporting Person Date
By: Baker Bros. Advisors (GP) LLC, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 11/08/2016
Signature of Reporting Person Date
By: Baker Bros. Advisors LP, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 11/08/2016
Signature of Reporting Person Date
Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to 667, L.P., pursuant to authority granted by Baker Biotech Capital, L.P., GP to 667, L.P. Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 11/08/2016
Signature of Reporting Person Date
Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to BAKER BROTHERS LIFE SCIENCES, L.P., pursuant to authority granted by Baker Brothers Life Sciences Capital, L.P., GP to Baker Brothers Life Sciences, L.P. Name: Scott L. Lessing /s/ Scott L. Lessing 11/08/2016
Signature of Reporting Person Date
Explanation of Responses:
( 1 )Reflects shares of common stock of Seattle Genetics, Inc. (the "Issuer") held directly by Felix J. Baker.
( 2 )Reflects shares of common stock of the Issuer held directly by Julian C. Baker.
( 3 )The price reported in Column 4 is a weighted average price. These shares were traded by 667, L.P. ("667") and Baker Brothers Life Sciences, L.P. ("Life Sciences") in multiple transactions at prices ranging from $58.32 to $59.20, inclusive. The reporting persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares traded at each separate price within the range set forth in this footnote.
( 4 )After giving effect to the transactions reported herein and as a result of their ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker each may be deemed to have an indirect pecuniary interest in the Issuer's shares of Common Stock reported in column 5 of Table I directly held by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.
( 5 )After giving effect to the transactions reported herein and as a result of their ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Issuer's shares of Common Stock reported in column 5 of Table I directly held by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences
( 6 )The price reported in Column 4 is a weighted average price. These shares were traded by 667 and Life Sciences in multiple transactions at prices ranging from $59.17 to $59.50, inclusive. The reporting persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares traded at each separate price within the range set forth in this footnote.
( 7 )Includes beneficial ownership of 14,400 previously issued restricted stock units payable solely in common shares issued to Felix Baker in his capacity as a director of the Issuer pursuant to the Amended and Restated 2007 Equity Incentive Plan of which the fund may be deemed to own a portion and 30,000 shares received previously from exercise of 30,000 stock options of the Issuer that were issued to Felix J. Baker in his capacity as a director of the Issuer, of which the fund may be deemed to own a portion.
( 8 )Baker Bros. Advisors LP (the "Adviser") serves as the Investment Adviser to Life Sciences and 667 (collectively the "Funds"). In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are principals of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the inve stment and voting power of the securities held by the Funds.
( 9 )Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

Remarks:
Felix J. Baker is a director of Seattle Genetics, Inc. (the "Issuer"). By virtue of his representation on the Board of Directors of the Issuer, for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, the reporting persons are deemed directors by deputization of the Issuer.

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