X0306 4 2021-02-11 0 0001656536 Decibel Therapeutics, Inc. DBTX 0001842129 Foy Matthew C/O DECIBEL THERAPEUTICS, INC. 1325 BOYLSTON STREET, SUITE 500 BOSTON MA 02215 1 0 1 0 Stock Option (right to buy) 18.00 2021-02-11 4 A 0 20000 0.00 A 2031-02-10 Common Stock 20000 20000 D The option was granted on February 11, 2021 for 20,000 shares. The shares underlying the option vest in equal monthly installments until the third anniversary of the grant date, subject to the reporting person's continued service. /s/ Ronald Vigliotta, Attorney-in-Fact 2021-02-16