X0206 3 2021-05-19 0 0001664106 LogicBio Therapeutics, Inc. LOGC 0001863053 Gruskin Daniel C/O LOGICBIO THERAPEUTICS, INC. 65 HAYDEN AVE, FLOOR 2 LEXINGTON MA 02421 0 1 0 0 Chief Medical Officer Employee Stock Option (Right to buy) 7.92 2030-08-06 Common Stock 85000 D Employee Stock Option (Right to buy) 7.76 2031-02-23 Common Stock 155701 D Restricted Stock Units 0.00 Common Stock 4798 D The options were granted by the Issuer pursuant to its 2018 Equity Incentive Plan. The options will vest over four years: 25% of the options will vest on the August 6, 2021 with the remaining 75% vesting in equal monthly installments thereafter, subject to the reporting person's continued service with the Issuer on each vesting date. The options were granted by the Issuer pursuant to its 2018 Equity Incentive Plan. The options will vest over four years: 25% of the options will vest on January 1, 2022 with the remaining 75% vesting in equal monthly installments thereafter, subject to the reporting person's continued service with the Issuer on each vesting date. Each restricted stock unit ("RSU") represents a contingent right to receive one share of the Issuer's common stock. The RSUs will fully vest on August 6, 2021, subject to the terms and conditions of the award and the Issuer's 2018 Equity Incentive Plan; provided, that if the reporting person's employment is terminated by the Issuer without "cause" or by the reporting person for "good reason" (as defined in the reporting person's employment agreement) prior to August 6, 2021, all such RSUs will vest on the date of termination. /s/ Jonathan Quick, as Attorney-in-Fact 2021-05-20