Decibel Therapeutics (DBTX) SC 13G Decibel Therapeutics / GV 2016 ownership change

EXHIBIT A

Agreement of Joint Filing

The undersigned hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Common Stock of Decibel Therapeutics, Inc. shall be filed on behalf of each of the undersigned and that this Agreement shall be filed as an exhibit to such Schedule 13G.

Date: February 11, 2022

GV 2016, L.P.
By: GV 2016 GP, L.P., its General Partner
By: GV 2016 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2016 GP, L.P.
By: GV 2016 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2016 GP, L.L.C.
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2017, L.P.
By: GV 2017 GP, L.P., its General Partner
By: GV 2017 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2017 GP, L.P.
By: GV 2017 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2017 GP, L.L.C
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2019, L.P.
By: GV 2019 GP, L.P., its General Partner
By: GV 2019 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary

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GV 2019 GP, L.P.
By: GV 2019 GP, L.L.C., its General Partner
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
GV 2019 GP, L.L.C.
By: Alphabet Holdings LLC, its Sole Member
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
Alphabet Holdings LLC
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Secretary
XXVI Holdings Inc.
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Assistant Secretary
Alphabet Inc.
By:	/s/ Kathryn W. Hall
Name: Kathryn W. Hall
Title: Assistant Secretary

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