X0306 4 2020-05-29 0 0001571498 Epizyme, Inc. EPZM 0001507678 Legorreta Pablo G. C/O RP MANAGEMENT, LLC, 110 E. 59TH ST., 33RD FLOOR NEW YORK NY 10022 1 0 1 0 0001507673 RP Management, LLC C/O RP MANAGEMENT, LLC 110 E. 59TH ST., 33RD FLOOR NEW YORK NY 10022 1 0 1 0 0001793690 RPI Finance Trust C/O RP MANAGEMENT, LLC 110 E. 59TH ST., 33RD FLOOR NEW YORK NY 10022 1 0 1 0 Common Stock 9166667 I See footnotes Stock Option (Right to Buy) 13.51 2029-11-05 Common Stock 34408 34408 D Stock Option (Right to Buy) 17.55 2020-05-29 4 A 0 14103 0.00 A 2021-05-29 2029-05-29 Common Stock 14103 14103 D Represents (i) 6,666,667 shares of the Issuer's common stock and (ii) 2,500,000 shares of the Issuer's common stock, in each case acquired by RPI Finance Trust ("RPIFT") pursuant to that certain Purchase Agreement, dated November 4, 2019, by and between the Issuer and RPIFT. This Form 4 is being jointly filed by RP Management, LLC ("RP Management"), RPIFT and Pablo G. Legorreta (collectively, the "Reporting Persons"). RP Management, as the manager of RPIFT, and Mr. Legorreta, as the manager of RP Management, may be deemed to have beneficial ownership under Section 13 of the Securities Exchange Act of 1934, as amended (the "Exchange Act") of the securities beneficially owned by RPIFT. RP Management and Mr. Legorreta disclaim beneficial ownership of the securities indicated except to the extent of their pecuniary interest therein, and the reporting herein of such securities shall not be construed as an admission that RP Management and/or Mr. Legorreta are the beneficial owners thereof for purposes of Section 16 of the Exchange Act or for any other purpose. Mr. Legorreta serves on the board of directors of the Issuer as a representative of RPIFT. (Continued from Footnote 2) Each of RPIFT and RP Management, LLC may be deemed to be a director by deputization of the Issuer for purposes of Section 16(b)-3(d) of the Exchange Act. This option was granted to Mr. Legorreta on November 6, 2019 pursuant to the Issuer's 2013 Stock Incentive Plan with respect to 34,408 shares of common stock, in connection with Mr. Legorreta's election to the board of directors of the Issuer. This option vests as to 25% of the shares on the first anniversary of the grant date and as to an additional 2.0833% of the shares at the end of each successive month following the first anniversary of the grant date until the fourth anniversary of the grant date. Mr. Legorreta is deemed to hold the stock option and the shares issuable thereunder for the benefit of RP Management. Mr. Legorreta is the manager of RP Management. Any exercise of the stock option, when vested, or sale of the shares issuable upon exercise shall be at the direction of RP Management and the proceeds of the sale of the shares issuable upon exercise shall be delivered to RP Management. The proceeds of the sale of the shares issuable under the stock option will be offset against the management fee payable to RP Management by certain indirect owners (the "Funds") of RPIFT, all of which are managed by RP Management. (Continued from Footnote 6) Mr. Legorreta and such Funds disclaim beneficial ownership of the securities indicated except to the extent of their pecuniary interest therein, and the reporting herein of such securities shall not be construed as an admission that Mr. Legorreta or any of such Funds is the beneficial owner thereof for purposes of Section 16 of the Exchange Act or for any other purpose. Mr. Legorreta serves on the board of directors of the Issuer as a representative of RPIFT. Each of RPIFT and RP Management may be deemed to be a director by deputization of the Issuer for purposes of Section 16(b)-3(d) of the Exchange Act. This stock option will vest in full on May 29, 2021, subject to Mr. Legorreta's continued service as a director. In the event of a change in control of the Issuer, the option will become exercisable in full. /s/ Pablo G. Legorreta 2020-06-02 RP Management, LLC, By: /s/ Pablo G. Legorreta, Chief Executive Officer 2020-06-02 RPI Finance Trust, By: RP Management, LLC, its Administrator, /s/ Pablo G. Legorreta, Chief Executive Officer 2020-06-02