X0206 3 2023-11-02 0 0001907108 Lexeo Therapeutics, Inc. LXEO 0001994981 McCormac Paul C/O LEXEO THERAPEUTICS, INC. 345 PARK AVENUE SOUTH, FLOOR 6 NEW YORK NY 10010 0 1 0 0 Chief Technical Officer Common Stock 14158 D Series B convertible preferred stock Common Stock 2743 D Employee Stock Option (right to buy) 2.33 2031-03-21 Common Stock 46001 D Employee Stock Option (right to buy) 4.87 2031-11-14 Common Stock 112028 D Employee Stock Option (right to buy) 11.02 2033-08-21 Common Stock 9438 D Each share of Series B convertible preferred stock is convertible into Common Stock on a 1-for-10.594230 at any time at the Reporting Person's election, and automatically upon the closing of the Issuer's initial public offering without payment or further consideration. Excludes shares of Common Stock issuable upon the closing of the Issuer's initial public offering pursuant to anti-dilution adjustment provisions of the Series B convertible preferred stock. The shares have no expiration date. 25% of the shares underlying the option vested on March 22, 2022, and 1/48th of the shares underlying the option vested or shall vest in monthly installments thereafter, subject to the Reporting Person's continuous service. 25% of the shares underlying the option vested on August 11, 2022, and 1/48th of the shares underlying the option vested or shall vest in monthly installments thereafter, subject to the Reporting Person's continuous service. 25% of the shares underlying the option shall vest on August 22, 2024, and 1/48th of the shares underlying the option shall vest in monthly installments thereafter, subject to the Reporting Person's continuous service. Exhibit List - Exhibit 24 - Power of Attorney /s/ Jenny Robertson, Attorney-in-Fact 2023-11-02