X0306 4 2021-08-11 0 0001815442 Kymera Therapeutics, Inc. KYMR 0001742766 ATLAS VENTURE ASSOCIATES X, L.P. 300 TECHNOLOGY SQUARE, 8TH FLOOR CAMBRIDGE MA 02139 0 0 1 0 0001742765 Atlas Venture Associates X, LLC 300 TECHNOLOGY SQUARE, 8TH FLOOR CAMBRIDGE MA 02139 0 0 1 0 Common Stock 2021-08-11 4 S 0 242133 61.00 D 0 D Common Stock 5763012 I See footnote The shares reported herein give effect to the pro rata distribution of shares by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"), on May 18, 2021, for no additional consideration to its limited partners and its general partner, Atlas Venture Associates X, L.P. ("AVA X LP"), subsequent to the Reporting Persons' last Section 16 filing reporting ownership of the Issuer's Common Stock. As the distribution of such shares constituted only a change in the form of the Reporting Persons' ownership in such shares, the Reporting Persons were not required to report the distribution pursuant to Section 16. The shares are held directly by AVA X LP. Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. AVA X LLC disclaims Section 16 beneficial ownership of the securities held by AVA X LP except to the extent of its pecuniary interest therein, if any. These shares are held directly by Atlas Venture Fund X. The general partner of Atlas Venture Fund X is AVA X LP and the general partner of AVA X LP is AVA X LLC. Each of AVA X LP and AVA LLC disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of its respective pecuniary interest therein, if any. Atlas Venture Associates X, L.P., By: Atlas Venture Associates X, LLC, Its: General Partner, By: /s/ Ommer Chohan, Chief Financial Officer 2021-08-12 Atlas Venture Associates X, LLC, By: /s/ Ommer Chohan, Chief Financial Officer 2021-08-11