KYMR

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 10

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 723,246

F8 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $38.97 to $39.85 inclusive.

F9 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 9

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 743,484

F8 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F6 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $37.97 to $38.96 inclusive.

F9 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 8

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 782,090

F8 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F5 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $36.97 to $37.96 inclusive.

F9 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 7

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 790,859

F8 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $35.96 to $36.91 inclusive.

F9 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 6

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 796,889

F8 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.96 to $35.94 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold each separate price within the ranges set forth in footnotes (2), (4), (5), (6) and (7).

F9 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 5

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,173,216

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $38.97 to $39.85 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 4

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,269,602

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F6 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $37.97 to $38.96 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 3

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,453,470

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F5 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $36.97 to $37.96 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 2

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,495,233

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $35.96 to $36.91 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-019440 · form4-07092024_090724.xml · nonDerivative · entry 1

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,523,951

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.96 to $35.94 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold each separate price within the ranges set forth in footnotes (2), (4), (5), (6) and (7).

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0000950170-24-079666 · ownership.xml · derivative · entry 2

Mainolfi Nello · CIK 0001821189 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 288,456

Underlying: Common Stock · 18,773 shares

Expires 2030-05-13

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: The shares underlying this stock option vest in forty-eight (48) equal monthly installments following the vesting commencement date of May 14, 2020, subject to the reporting person's continued employment through each vesting date.

SEC source: 0000950170-24-079666 · ownership.xml · nonDerivative · entry 1

Mainolfi Nello · CIK 0001821189 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 649,959

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000950170-24-078790 · ownership.xml · derivative · entry 2

Jacobs Bruce N. · CIK 0001821074 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 104,899

Underlying: Common Stock · 25,000 shares

Expires 2029-08-28

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: Twenty-five percent (25%) of the shares underlying this stock option vested on July 1, 2020 and the remaining shares shall vest in equal monthly installments over the remaining thirty-six (36) months, subject to the reporting person's continued employment through each vesting date.

SEC source: 0000950170-24-078790 · ownership.xml · nonDerivative · entry 1

Jacobs Bruce N. · CIK 0001821074 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 168,554

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · balance_after: This number includes 1,203 shares acquired under the Registrant's employee stock purchase plan on June 1, 2024.

SEC source: 0000950170-24-075332 · ownership.xml · derivative · entry 2

Mainolfi Nello · CIK 0001821189 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 505,559

Underlying: Common Stock · 14,413 shares

Expires 2029-11-13

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The shares underlying this stock option vest in forty-eight (48) equal monthly installments following the vesting commencement date of November 14, 2019, subject to the reporting person's continued employment through each vesting date.

SEC source: 0000950170-24-075332 · ownership.xml · nonDerivative · entry 1

Mainolfi Nello · CIK 0001821189 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 631,186

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · balance_after: This number includes 1,203 shares acquired under the Registrant's employee stock purchase plan on June 1, 2024.

SEC source: 0000950170-24-075709 · ownership.xml · derivative · entry 1

MARAGANORE JOHN · CIK 0001180432 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000950170-24-075705 · ownership.xml · derivative · entry 1

Esposito Pamela · CIK 0001744425 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000950170-24-075713 · ownership.xml · derivative · entry 1

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

F2 · ownership.direct: This option was granted to the Reporting Person, a director of the Issuer. The proceeds of any sale of shares of common stock issued to the Reporting Person upon exercise of this option will be transferred to Atlas Venture Life Science Advisors, LLC and as such, the Reporting Person disclaims ownership of such securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except to the extent of his pecuniary interest therein, if any.

SEC source: 0000950170-24-075712 · ownership.xml · derivative · entry 1

Albers Jeffrey W. · CIK 0001638474 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000950170-24-075711 · ownership.xml · derivative · entry 1

Ridloff Elena · CIK 0001772518 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000950170-24-075710 · ownership.xml · derivative · entry 1

Hrustanovic Gorjan · CIK 0001821194 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

F2 · ownership.direct: The Reporting Person is a member of BVF Partners L.P. ("BVF") and is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the equity grants to BVF. As such, the Reporting Person disclaims beneficial ownership of the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except to the extent of his pecuniary interest therein, if any.

SEC source: 0000950170-24-075708 · ownership.xml · derivative · entry 1

Morgan Leigh · CIK 0001935887 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000950170-24-075707 · ownership.xml · derivative · entry 1

Sandor Victor · CIK 0001620368 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2034-06-17

F1 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

SEC source: 0000921895-24-001488 · form407422010_06282024.xml · derivative · entry 4

BVF PARTNERS L P/IL · CIK 0001055947 · Director · See Remarks and Footnotes

BIOTECHNOLOGY VALUE FUND L P · CIK 0000918923 · Director · See Remarks and Footnotes

BVF I GP LLC · CIK 0001803805 · Director · See Remarks and Footnotes

BIOTECHNOLOGY VALUE FUND II LP · CIK 0001102444 · Director · See Remarks and Footnotes

BVF II GP LLC · CIK 0001803806 · Director · See Remarks and Footnotes

Biotechnology Value Trading Fund OS LP · CIK 0001660683 · Director · See Remarks and Footnotes

BVF Partners OS Ltd. · CIK 0001660684 · Director · See Remarks and Footnotes

BVF GP HOLDINGS LLC · CIK 0001803809 · Director · See Remarks and Footnotes

BVF INC/IL · CIK 0001056807 · Director · See Remarks and Footnotes

LAMPERT MARK N · CIK 0001233840 · Director · See Remarks and Footnotes

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 16,000

Underlying: Common Stock, $0.0001 par value · 16,000 shares

Expires 2034-06-17

F5 · security: Partners, BVF Inc. and Mr. Lampert may be deemed to have a pecuniary interest in the securities reported owned herein due to a certain agreement between Partners and Gorjan Hrustanovic, who serves on the Issuer's board of directors and as a member of Partners, pursuant to which Mr. Hrustanovic is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the securities reported owned herein to Partners. As such, Mr. Hrustanovic disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

F6 · derivative.exercise_date: The shares underlying this stock option shall vest in full upon the earlier to occur of (i) June 18, 2025 and (ii) the date of the next annual meeting of the Issuer's stockholders.

F5 · ownership.direct: Partners, BVF Inc. and Mr. Lampert may be deemed to have a pecuniary interest in the securities reported owned herein due to a certain agreement between Partners and Gorjan Hrustanovic, who serves on the Issuer's board of directors and as a member of Partners, pursuant to which Mr. Hrustanovic is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the securities reported owned herein to Partners. As such, Mr. Hrustanovic disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

F5 · ownership.nature: Partners, BVF Inc. and Mr. Lampert may be deemed to have a pecuniary interest in the securities reported owned herein due to a certain agreement between Partners and Gorjan Hrustanovic, who serves on the Issuer's board of directors and as a member of Partners, pursuant to which Mr. Hrustanovic is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the securities reported owned herein to Partners. As such, Mr. Hrustanovic disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 6

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 802,022

F5 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.95 to $34.985 inclusive.

F6 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 5

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,548,400

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.95 to $34.985 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 4

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 803,792

F5 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $35.99 to $36.29 inclusive.

F6 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 3

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 804,212

F5 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.95 to $35.88 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2), (4) and (7).

F6 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 2

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,556,830

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $35.99 to $36.29 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-017005 · form4-06142024_100645.xml · nonDerivative · entry 1

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,558,827

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.95 to $35.88 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2), (4) and (7).

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0000950170-24-070966 · ownership.xml · derivative · entry 4

Horobin Joanna · CIK 0001560959 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 33,195

Underlying: Common Stock · 8,500 shares

Expires 2029-05-22

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: These transactions were effected pursuant to a Rule 10b5-1 trading plan dated March 8, 2024 adopted by the reporting person.

F4 · derivative.exercise_date: The shares underlying this stock option vest in forty-eight (48) equal monthly installments following the vesting commencement date of May 16, 2018, subject to the reporting person's continued employment through each vesting date.

SEC source: 0000950170-24-070966 · ownership.xml · nonDerivative · entry 3

Horobin Joanna · CIK 0001560959 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

F1 · kind: These transactions were effected pursuant to a Rule 10b5-1 trading plan dated March 8, 2024 adopted by the reporting person.

F3 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $32.88 to $33.39, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0000950170-24-070966 · ownership.xml · nonDerivative · entry 2

Horobin Joanna · CIK 0001560959 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 6,313

F1 · kind: These transactions were effected pursuant to a Rule 10b5-1 trading plan dated March 8, 2024 adopted by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $31.88 to $32.86, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0000950170-24-070966 · ownership.xml · nonDerivative · entry 1

Horobin Joanna · CIK 0001560959 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 8,500

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: These transactions were effected pursuant to a Rule 10b5-1 trading plan dated March 8, 2024 adopted by the reporting person.

SEC source: 0000950170-24-063947 · ownership.xml · nonDerivative · entry 1

Chadwick Jeremy G · CIK 0001388406 · Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 44,183

F1 · kind: Represents shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of restricted stock units. Such sales were automatic and not in the discretion of the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $34.65 to $35.2963, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0000950170-24-038905 · ownership.xml · derivative · entry 2

BAKER BROS. ADVISORS LP · CIK 0001263508 · Director

667, L.P. · CIK 0001551139 · Director

Baker Bros. Advisors (GP) LLC · CIK 0001580575 · Director

Baker Brothers Life Sciences LP · CIK 0001363364 · Director

BAKER FELIX · CIK 0001087940 · Director

BAKER JULIAN · CIK 0001087939 · Director

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 32,000

Underlying: Common Stock · 32,000 shares

Expires 2034-03-27

F1 · derivative.exercise_date: 32,000 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Kymera Therapeutics, Inc. (the "Issuer") were granted under the Issuer's 2020 Stock Option and Incentive Plan to Felix J. Baker, a managing member of Baker Bros. Advisors (GP) LLC (the "Adviser GP") in his capacity as a director of the Issuer. The Stock Options have a strike price of $40.20 per share, and vest in equal monthly installments over a three year period commencing on March 28, 2024, subject to Felix J. Baker's continued service on the board of directors of the Issuer (the "Board") and expire on March 27, 2034. Felix J. Baker serves on the Board as a representative of Baker Brothers Life Sciences, L.P. ("Life Sciences") and 667, L.P. ("667", and together with Life Sciences, the "Funds").

F1 · derivative.expiration_date: 32,000 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Kymera Therapeutics, Inc. (the "Issuer") were granted under the Issuer's 2020 Stock Option and Incentive Plan to Felix J. Baker, a managing member of Baker Bros. Advisors (GP) LLC (the "Adviser GP") in his capacity as a director of the Issuer. The Stock Options have a strike price of $40.20 per share, and vest in equal monthly installments over a three year period commencing on March 28, 2024, subject to Felix J. Baker's continued service on the board of directors of the Issuer (the "Board") and expire on March 27, 2034. Felix J. Baker serves on the Board as a representative of Baker Brothers Life Sciences, L.P. ("Life Sciences") and 667, L.P. ("667", and together with Life Sciences, the "Funds").

F2 · ownership.nature: Pursuant to the policies of Baker Bros. Advisors LP (the "Adviser"), Felix J. Baker does not have any right to any of the Issuer's securities issued as part of his service on the Board and the Funds are entitled to receive all the pecuniary interest in the securities issued. The Funds each own an indirect proportionate pecuniary interest in the Stock Options. Solely as a result of Felix J. Baker's and Julian C. Baker's ownership interests in (i) the general partners of the Funds and (ii) the Funds, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in the Stock Options (i.e. no direct pecuniary interest). Pursuant to the policies of the Adviser, the Adviser has voting and dispositive power over the Stock Options and any Common Stock acquired as a result of the exercise of the Stock Options.

F3 · ownership.nature: The Adviser serves as the investment adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. The Adviser GP is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are managing members of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds.

F4 · ownership.nature: Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

F6 · ownership.nature: The acquisition of Stock Options reported on this form represents a single grant to Felix J. Baker of 32,000 Stock Options on Table II. This grant of 32,000 Stock Options for Felix J. Baker is reported for each of the Funds as each has an indirect pecuniary interest in such securities.

F7 · ownership.nature: After giving effect to the transaction reported herein and as a result of their ownership interest in (i) Baker Brothers Life Sciences Capital, L.P. and (ii) Life Sciences, Julian C. Baker and Felix J.Baker each may be deemed to have an indirect pecuniary interest in the Stock Options reported in column 9 of Table II held for the benefit of Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to their interest in Life Sciences and Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

SEC source: 0000950170-24-038905 · ownership.xml · derivative · entry 1

BAKER BROS. ADVISORS LP · CIK 0001263508 · Director

667, L.P. · CIK 0001551139 · Director

Baker Bros. Advisors (GP) LLC · CIK 0001580575 · Director

Baker Brothers Life Sciences LP · CIK 0001363364 · Director

BAKER FELIX · CIK 0001087940 · Director

BAKER JULIAN · CIK 0001087939 · Director

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 32,000

Underlying: Common Stock · 32,000 shares

Expires 2034-03-27

F1 · derivative.exercise_date: 32,000 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Kymera Therapeutics, Inc. (the "Issuer") were granted under the Issuer's 2020 Stock Option and Incentive Plan to Felix J. Baker, a managing member of Baker Bros. Advisors (GP) LLC (the "Adviser GP") in his capacity as a director of the Issuer. The Stock Options have a strike price of $40.20 per share, and vest in equal monthly installments over a three year period commencing on March 28, 2024, subject to Felix J. Baker's continued service on the board of directors of the Issuer (the "Board") and expire on March 27, 2034. Felix J. Baker serves on the Board as a representative of Baker Brothers Life Sciences, L.P. ("Life Sciences") and 667, L.P. ("667", and together with Life Sciences, the "Funds").

F1 · derivative.expiration_date: 32,000 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Kymera Therapeutics, Inc. (the "Issuer") were granted under the Issuer's 2020 Stock Option and Incentive Plan to Felix J. Baker, a managing member of Baker Bros. Advisors (GP) LLC (the "Adviser GP") in his capacity as a director of the Issuer. The Stock Options have a strike price of $40.20 per share, and vest in equal monthly installments over a three year period commencing on March 28, 2024, subject to Felix J. Baker's continued service on the board of directors of the Issuer (the "Board") and expire on March 27, 2034. Felix J. Baker serves on the Board as a representative of Baker Brothers Life Sciences, L.P. ("Life Sciences") and 667, L.P. ("667", and together with Life Sciences, the "Funds").

F2 · ownership.nature: Pursuant to the policies of Baker Bros. Advisors LP (the "Adviser"), Felix J. Baker does not have any right to any of the Issuer's securities issued as part of his service on the Board and the Funds are entitled to receive all the pecuniary interest in the securities issued. The Funds each own an indirect proportionate pecuniary interest in the Stock Options. Solely as a result of Felix J. Baker's and Julian C. Baker's ownership interests in (i) the general partners of the Funds and (ii) the Funds, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in the Stock Options (i.e. no direct pecuniary interest). Pursuant to the policies of the Adviser, the Adviser has voting and dispositive power over the Stock Options and any Common Stock acquired as a result of the exercise of the Stock Options.

F3 · ownership.nature: The Adviser serves as the investment adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. The Adviser GP is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are managing members of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds.

F4 · ownership.nature: Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

F5 · ownership.nature: After giving effect to the transaction reported herein and as a result of their ownership interest in (i) Baker Biotech Capital, L.P. and (ii) 667, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Stock Options reported in column 9 of Table II held for the benefit of 667, a limited partnership of which the sole general partner is BakerBiotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to their interest in 667 and Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

F6 · ownership.nature: The acquisition of Stock Options reported on this form represents a single grant to Felix J. Baker of 32,000 Stock Options on Table II. This grant of 32,000 Stock Options for Felix J. Baker is reported for each of the Funds as each has an indirect pecuniary interest in such securities.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 12

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 806,697

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F10 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.1413 to $41.43 inclusive.

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 11

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 807,026

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F9 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.1375 to $41.13 inclusive.

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 10

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 817,437

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F8 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.13 to $40.1296 inclusive.

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 9

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,570,665

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F10 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.1413 to $41.43 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 8

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,572,258

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F9 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.1375 to $41.13 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 7

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,621,849

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F8 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.13 to $40.1296 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 6

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 819,151

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F5 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.2712 to $41.7267 inclusive.

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 5

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 819,305

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.26 to $41.2563 inclusive.

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 4

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 821,538

F6 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund I, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.2558 to $40.2537 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2), (4), (5), (8), (9) and (10).

F7 · ownership.nature: The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF I"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF I. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 3

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,629,975

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F5 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.2712 to $41.7267 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 2

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,630,756

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.26 to $41.2563 inclusive.

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.

SEC source: 0001415889-24-008155 · form4-03152024_110334.xml · nonDerivative · entry 1

Booth Bruce · CIK 0001451612 · Director

10b5-1 filing: Plan reported

Ownership: Indirect · See footnote

Disclosed balance after: 4,641,602

F1 · kind: This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. on January 22, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.2558 to $40.2537 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2), (4), (5), (8), (9) and (10).

F3 · ownership.nature: These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extend of his pecuniary interest therein, if any.