0000919574-24-002174.txt : 20240325 0000919574-24-002174.hdr.sgml : 20240325 20240325210345 ACCESSION NUMBER: 0000919574-24-002174 CONFORMED SUBMISSION TYPE: 3 PUBLIC DOCUMENT COUNT: 1 CONFORMED PERIOD OF REPORT: 20240320 FILED AS OF DATE: 20240325 DATE AS OF CHANGE: 20240325 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Casdin Partners GP, LLC CENTRAL INDEX KEY: 0001534260 ORGANIZATION NAME: STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 3 SEC ACT: 1934 Act SEC FILE NUMBER: 001-40791 FILM NUMBER: 24780742 BUSINESS ADDRESS: STREET 1: 1350 AVENUE OF THE AMERICAS STREET 2: SUITE 1140 CITY: NEW YORK STATE: NY ZIP: 10019 BUSINESS PHONE: 212.300.5575 MAIL ADDRESS: STREET 1: 1350 AVENUE OF THE AMERICAS STREET 2: SUITE 1140 CITY: NEW YORK STATE: NY ZIP: 10019 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Casdin Capital, LLC CENTRAL INDEX KEY: 0001534261 ORGANIZATION NAME: STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 3 SEC ACT: 1934 Act SEC FILE NUMBER: 001-40791 FILM NUMBER: 24780744 BUSINESS ADDRESS: STREET 1: 1350 AVENUE OF THE AMERICAS STREET 2: SUITE 2600 CITY: NEW YORK STATE: NY ZIP: 10019 BUSINESS PHONE: 212.300.5575 MAIL ADDRESS: STREET 1: 1350 AVENUE OF THE AMERICAS STREET 2: SUITE 2600 CITY: NEW YORK STATE: NY ZIP: 10019 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Casdin Eli CENTRAL INDEX KEY: 0001534264 ORGANIZATION NAME: FILING VALUES: FORM TYPE: 3 SEC ACT: 1934 Act SEC FILE NUMBER: 001-40791 FILM NUMBER: 24780741 MAIL ADDRESS: STREET 1: 1350 AVENUE OF THE AMERICAS STREET 2: SUITE 1140 CITY: NEW YORK STATE: NY ZIP: 10019 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Casdin Partners Master Fund, L.P. CENTRAL INDEX KEY: 0001534265 ORGANIZATION NAME: STATE OF INCORPORATION: E9 FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 3 SEC ACT: 1934 Act SEC FILE NUMBER: 001-40791 FILM NUMBER: 24780743 BUSINESS ADDRESS: STREET 1: WALKER HOUSE STREET 2: 87 MARY STREET CITY: GEORGE TOWN STATE: E9 ZIP: KY1-9001 BUSINESS PHONE: 212.300.5575 MAIL ADDRESS: STREET 1: WALKER HOUSE STREET 2: 87 MARY STREET CITY: GEORGE TOWN STATE: E9 ZIP: KY1-9001 ISSUER: COMPANY DATA: COMPANY CONFORMED NAME: 2seventy bio, Inc. CENTRAL INDEX KEY: 0001860782 STANDARD INDUSTRIAL CLASSIFICATION: PHARMACEUTICAL PREPARATIONS [2834] ORGANIZATION NAME: 03 Life Sciences IRS NUMBER: 863658454 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 BUSINESS ADDRESS: STREET 1: 60 BINNEY STREET CITY: CAMBRIDGE STATE: MA ZIP: 02210 BUSINESS PHONE: 339-499-9300 MAIL ADDRESS: STREET 1: 60 BINNEY STREET CITY: CAMBRIDGE STATE: MA ZIP: 02210 3 1 ownership.xml X0206 3 2024-03-20 0 0001860782 2seventy bio, Inc. TSVT 0001534261 Casdin Capital, LLC 1350 AVENUE OF THE AMERICAS SUITE 2600 NEW YORK NY 10019 1 0 0 0 0001534265 Casdin Partners Master Fund, L.P. 1350 AVENUE OF THE AMERICAS SUITE 2600 NEW YORK NY 10019 1 0 0 0 0001534260 Casdin Partners GP, LLC 1350 AVENUE OF THE AMERICAS SUITE 2600 NEW YORK NY 10019 1 0 0 0 0001534264 Casdin Eli 1350 AVENUE OF THE AMERICAS SUITE 2600 NEW YORK NY 10019 1 0 0 0 Common Stock, par value $0.0001 per share 1182623 I See footnote Common Stock, par value $0.0001 per share 16600 D Stock Options (Right to buy) 4.54 2034-03-20 Common Stock, par value $0.0001 per share 33400 D Total Return Swap Common Stock, par value $0.0001 per share 599935 I See footnote The securities are owned directly by Casdin Partners Master Fund, LP (the "Master Fund") and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC, the investment adviser to the Master Fund, (ii) Casdin Partners GP, LLC, the general partner of the Master Fund, and (ii) Eli Casdin, the managing member of Casdin Capital, LLC and Casdin Partners GP, LLC. This restricted stock unit award vests ratable over three years in annual installments with the first installment vesting on March 20, 2025, subject to the Reporting Person's continued service through the applicable vesting date. The securities are owned directly by Eli Casdin. This stock option vests ratably over three years in annual installments with the first installment vesting on March 20, 2025, subject to the Reporting Person's continued service through the applicable vesting date. The Master Fund has entered into certain cash-settled total return swap agreements (the "Swap Agreements"), which represent economic exposure to an aggregate of 599,935.15 notional shares of the Issuer's Common Stock, par value $0.0001 per share. The Swap Agreements provide the Master Fund with economic results that are comparable to the economic results of ownership but do not provide it with the power to vote or direct the voting or dispose of or direct the disposition of the securities that are referenced by the Swap Agreements. Eli Casdin has been deputized to represent the Reporting Persons on the board of directors of the Issuer. By virtue of Mr. Casdin's representation, for purposes of Section 16 of the Securities Exchange Act of 1934 (the "Exchange Act"), each of the Reporting Persons may be deemed directors by deputization of the Issuer. Each Reporting Person disclaims beneficial ownership in the securities reported on this Form 3 except to the extent of its or his pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. Casdin Capital LLC, By: /s/ Eli Casdin, Managing Member 2024-03-25 Casdin Partners Master Fund, LP, By: Casdin Partners GP, LLC, its General Partner, By: /s/ Eli Casdin, Managing Member 2024-03-25 Casdin Partners GP LLC, By: /s/ Eli Casdin, Managing Member 2024-03-25 /s/ Eli Casdin, Eli Casdin 2024-03-25