X0306 4 2021-12-02 0 0001656536 Decibel Therapeutics, Inc. DBTX 0001842132 Trask Anna C/O DECIBEL THERAPEUTICS, INC. 1325 BOYLSTON STREET, SUITE 500 BOSTON MA 02215 0 1 0 0 See Remarks Common Stock 2021-12-02 4 S 0 4913 6.3695 D 2620 D Common Stock 2021-12-02 4 S 0 378 6.3352 D 2242 D These transactions were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.25 to $6.615, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, the issuer or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price with the ranges set forth in footnotes (2) and (3) of this Form 4. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.18 to $6.47, inclusive. CHIEF PEOPLE, COMMUNITY & CULTURE OFFICER /s/ Anna Trask 2021-12-06