X0206 3 2019-05-01 0 0001756262 TransMedics Group, Inc. TMDX 0001508051 Flagship Ventures Fund IV General Partner LLC C/O FLAGSHIP PIONEERING INC. 55 CAMBRIDGE PARKWAY, SUITE 800E CAMBRIDGE MA 02142 0 0 1 0 0001503559 Flagship Ventures Fund IV, L.P. C/O FLAGSHIP PIONEERING INC. 55 CAMBRIDGE PARKWAY, SUITE 800E CAMBRIDGE MA 02142 0 0 1 0 0001508053 Flagship Ventures 2007 General Partner LLC C/O FLAGSHIP PIONEERING INC. 55 CAMBRIDGE PARKWAY, SUITE 800E CAMBRIDGE MA 02142 0 0 1 0 0001508052 Flagship Ventures Fund 2007, L.P. C/O FLAGSHIP PIONEERING INC. 55 CAMBRIDGE PARKWAY, SUITE 800E CAMBRIDGE MA 02142 0 0 1 0 0001222012 AFEYAN NOUBAR C/O FLAGSHIP PIONEERING INC. 55 CAMBRIDGE PARKWAY, SUITE 800E CAMBRIDGE MA 02142 0 0 1 0 Common Stock 214285 I By Flagship Ventures Fund IV, L.P. Common Stock 268736 I By Flagship Ventures 2007, L.P. Series C Convertible Preferred Stock Common Stock 571428 I By Flagship Ventures Fund IV, L.P. Series D Convertible Preferred Stock Common Stock 400000 I By Flagship Ventures Fund IV, L.P. Series F Convertible Preferred Stock Common Stock 283460 I By Flagship Ventures Fund IV, L.P. Series C Convertible Preferred Stock Common Stock 359276 I By Flagship Ventures Fund 2007, L.P. Series D Convertible Preferred Stock Common Stock 171428 I By Flagship Ventures Fund 2007, L.P. Series F Convertible Preferred Stock Common Stock 128845 I By Flagship Ventures Fund 2007, L.P. Series B-1 Convertible Preferred Stock Common Stock 132817 I By Flagship Ventures Fund 2007, L.P. As of the date of this Form 3, the Common Stock reported herein is common stock of TransMedics, Inc. Immediately prior to the closing of the Issuer's initial public offering, pursuant to the Agreement and Plan of Merger and Reorganization by and among the Issuer, TransMedics, Inc. and TMDX, Inc., dated April 15, 2019 (the "Merger Agreement"), such common stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer on a 3.5-for-one basis (the "Common Stock Conversion"). The number of shares in Column 2 reflects the Reporting Person's holdings following the Common Stock Conversion. Shares held by Flagship Ventures Fund IV, L.P. ("Flagship Fund IV"). Flagship Ventures Fund IV General Partner LLC ("Flagship Fund IV GP") is the general partner of Flagship Fund IV. Noubar B. Afeyan, Ph.D. is a manager of Flagship Fund IV GP and, for purposes of Flagship Fund IV's investment in the Issuer, Dr. Afeyan may be deemed to have voting and investment power with respect to all shares held by Flagship Fund IV. Each of the reporting persons disclaims beneficial ownership of the shares except to the extent, if any, of his or its pecuniary interest therein. Shares held by Flagship Ventures Fund 2007, L.P. ("Flagship Fund 2007"). Flagship Ventures 2007 General Partner LLC ("Flagship Fund 2007 GP") is the general partner of Flagship Fund 2007. Dr. Afeyan is a manager of Flagship Fund 2007 GP and, for purposes of Flagship Fund 2007's investment in the Issuer, Dr. Afeyan may be deemed to have voting and investment power with respect to all shares held by Flagship Fund 2007. Each of the reporting persons disclaims beneficial ownership of the shares except to the extent, if any, of his or its pecuniary interest therein. As of the date of this Form 3, the Preferred Stock reported herein is preferred stock of TransMedics, Inc. Immediately prior to the closing of the Issuer's initial public offering, pursuant to the Merger Agreement, each outstanding share of Series C, Series D and Series F preferred stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer based on (i) the one-for-one ratio on which such shares of preferred stock of TransMedics Inc. are convertible into shares of common stock of TransMedics Inc. according to their terms and (ii) the 3.5-for-one ratio on which shares of common stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer (the "Preferred Stock Conversion"). The Preferred Stock has no expiration date. The number of shares in Column 3 reflects the Reporting Person's holdings following the Preferred Stock Conversion. As of the date of this Form 3, the Preferred Stock reported herein is preferred stock of TransMedics, Inc. Immediately prior to the closing of the Issuer's initial public offering, pursuant to the Merger Agreement, each outstanding share of Series B-1 preferred stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer based on (i) the ratio on which such shares of preferred stock of TransMedics Inc. are convertible into shares of common stock of TransMedics Inc. according to their terms, determined by dividing the original issue price of $3.416 per share by a conversion price of $12.365, and (ii) the 3.5-for-one ratio on which shares of common stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer (the "Series B-1 Preferred Stock Conversion"). The Preferred Stock has no expiration date. The number of shares in Column 3 reflects the Reporting Person's holdings following the Series B-1 Preferred Stock Conversion. Flagship Ventures Fund IV General Partner LLC, By: /s/ Noubar B. Afeyan, Name: Noubar B. Afeyan, Ph.D., Title: Manager 2019-05-01 Flagship Ventures Fund IV, L.P., By Flagship Ventures Fund IV General Partner LLC, its general partner, By: /s/ Noubar B. Afeyan, Name: Noubar B. Afeyan, Ph.D., Title: Manager 2019-05-01 Flagship Ventures Fund 2007 General Partner LLC, By: /s/ Noubar B. Afeyan, Name: Noubar B. Afeyan, Ph.D., Title: Manager 2019-05-01 Flagship Ventures Fund 2007, L.P., By Flagship Ventures Fund 2007 General Partner LLC, its general partner, By: /s/ Noubar B. Afeyan, Name: Noubar B. Afeyan, Ph.D., Title: Manager 2019-05-01 /s/ Noubar B. Afeyan, Noubar B. Afeyan 2019-05-01