Sec Form 4 Filing - Presidio Management Group XII, L.L.C. @ Silverback Therapeutics, Inc. - 2020-12-08

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 Presidio Management Group XII, L.L.C. 2. Issuer Name and Ticker or Trading Symbol Silverback Therapeutics, Inc. [ SBTX] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 1460 EL CAMINO REAL, SUITE100 3. Date of Earliest Transaction (MM/DD/YY) 12/08/2020 (Street) MENLO PARK, CA94025 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 12/08/2020 C 1,779,969 A 1,779,969 I By U.S. Venture Partners XII, L.P. ( 3 ) Common Stock 12/08/2020 C 289,198 A 2,069,167 I By U.S. Venture Partners XII, L.P. ( 3 ) Common Stock 12/08/2020 C 90,335 A 90,335 I By U.S. Venture Partners XII-A, L.P. ( 3 ) Common Stock 12/08/2020 C 14,677 A 105,012 I By U.S. Venture Partners XII-A, L.P. ( 3 ) Common Stock 12/08/2020 P( 1 ) 47,619 A $ 21 47,619 I Directly owned by Tansey

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 Preferred Series B Stock ( 2 ) 12/08/2020 C 6,609,027 ( 2 ) ( 2 ) Common Stock 1,779,969 $ 0 ( 2 ) 0 I By U.S. Venture Partners XII, L.P. ( 3 ) Preferred Series B Stock ( 2 ) 12/08/2020 C 335,417 ( 2 ) ( 2 ) Common Stock 90,335 $ 0 ( 2 ) 0 I By U.S. Venture Partners XII-A, L.P. ( 3 ) Preferred Series C Stock ( 2 ) 12/08/2020 C 1,073,793 ( 2 ) ( 2 ) Common Stock 289,198 $ 0 ( 2 ) 0 I By U.S. Venture Partners XII, L.P. ( 3 ) Preferred Series C Stock ( 2 ) 12/08/2020 C 54,496 ( 2 ) ( 2 ) Common Stock 14,677 $ 0 ( 2 ) 0 I By U.S. Venture Partners XII-A, L.P. ( 3 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Presidio Management Group XII, L.L.C. 1460 EL CAMINO REAL, SUITE100 MENLO PARK, CA94025 X U.S. Venture Partners XII, L.P. 1460 EL CAMINO REAL, SUITE 100 MENLO PARK, CA94025 X U.S. Venture Partners XII-A, L.P. 1460 EL CAMINO REAL, SUITE 100 MENLO PARK, CA94025 X Tansey Casey M 1460 EL CAMINO REAL, SUITE 100 MENLO PARK, CA94025 X Signatures Dale Holladay, Attorney-in-Fact for each Reporting Person 12/08/2020 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The shares were purchased in the Issuer's initial public offering. ( 2 )Series B and Series C Preferred Stock automatically converted into shares of the Issuer's Common Stock immediately upon the closing of the Issuer's imitial public offering, for no additional consideration at a rate of 1 share of Common Stock for each 3.713 shares of Preferred Stock, based on the conversion price currently in effect. The Preferred Stock had no expiration date. ( 3 )Presidio Management Group XII, L.L.C. ("PMG XII"), the general partner of each of U.S. Venture Partners XII, L.P. and U.S. Venture Partners XII-A, L.P. (together, the "USVP XII Funds"), has sole voting and dispositive power with respect to the shares held by the USVP XII. Casey Tansey is the sole managing partner of PMG XII and may be deemed to have voting and dispositive power over the reported securities held by the USVP XII Funds, and each of the foregoing persons disclaims beneficial ownership of such securities, except to the extent of any pecuniary interest therein.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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