KRRO

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 8

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,575

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

F5 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $77.01 to $78.00, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 7

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,835

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 6

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,858

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 5

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,914

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $74.51 to $74.90, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 4

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 8,029

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

F3 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $73.30 to $73.975, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 3

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 8,193

F1 · kind: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

F2 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $70.965 to $71.94, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 2

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 10,216

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: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

SEC source: 0000950170-24-115723 · ownership.xml · nonDerivative · entry 1

Agarwal Vineet · CIK 0001997973 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 9,263

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: The reported transactions occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 19, 2024.

SEC source: 0000950170-24-103068 · ownership.xml · derivative · entry 1

Cerio Jeffrey · CIK 0002033618 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,000

Underlying: Common Stock · 40,000 shares

Expires 2034-09-02

F1 · derivative.exercise_date: The shares subject to the option vest as to 25% of the shares on August 30, 2025, with the remainder vesting in 36 equal monthly installments thereafter, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0000950170-24-101535 · ownership.xml · derivative · entry 1

Knobil Katharine · CIK 0001768011 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,041

Underlying: Common Stock · 9,041 shares

Expires 2034-08-25

F1 · derivative.exercise_date: The shares subject to the option vest in three equal annual installments commencing from August 26, 2024, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0000950170-24-072564 · ownership.xml · derivative · entry 1

FORMELA JEAN FRANCOIS · CIK 0001030575 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

F2 · ownership.direct: The Reporting Person is a member of Atlas XI and is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the option to Atlas Venture Life Science Advisors, LLC. As such, the Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of his pecuniary interest therein, if any.

SEC source: 0000950170-24-072562 · ownership.xml · derivative · entry 1

Meyers Rachel · CIK 0002001472 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

SEC source: 0000950170-24-072557 · ownership.xml · derivative · entry 1

Bermingham Nessan · CIK 0001377759 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

SEC source: 0000950170-24-072556 · ownership.xml · derivative · entry 1

PEARSON TIMOTHY R · CIK 0001528617 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

SEC source: 0000950170-24-072567 · ownership.xml · derivative · entry 1

Behbahani Ali · CIK 0001613867 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

SEC source: 0000950170-24-072551 · ownership.xml · derivative · entry 1

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,190

Underlying: Common Stock · 5,190 shares

Expires 2034-06-10

F1 · derivative.exercise_date: The shares subject to the option vest in full on the earlier of (i) the one-year anniversary of the grant date or (ii) the date of the next annual meeting of stockholders, subject to continued service as a non-employee director through the applicable vesting date.

SEC source: 0000950170-24-068981 · ownership.xml · derivative · entry 1

Olugemo Olukemi · CIK 0002022212 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 65,000

Underlying: Common Stock · 65,000 shares

Expires 2034-06-02

F1 · derivative.exercise_date: The shares subject to the option vest as to 25% of the shares on May 13, 2025, with the remainder vesting in 36 equal monthly installments thereafter, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0001415889-24-011388 · form4-04232024_090441.xml · nonDerivative · entry 1

FORMELA JEAN FRANCOIS · CIK 0001030575 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 195,074

F1 · ownership.nature: These shares are held directly by Atlas Venture Opportunity Fund II, L.P. ("AVOF II"). Atlas Venture Associates Opportunity II, L.P. ("AVAO II LP") is the general partner of AVOF II. Atlas Venture Associates Opportunity II, LLC ("AVAO II LLC") is the general partner of AVAO II LP. The Reporting Person is a member of AVAO II LLC and disclaims Section 16 beneficial ownership of such shares, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001415889-24-011385 · form4-04232024_090431.xml · nonDerivative · entry 1

Atlas Venture Opportunity Fund II, L.P. · CIK 0001885327 · 10% owner

Atlas Venture Associates Opportunity II, LP · CIK 0001935814 · 10% owner

Atlas Venture Associates Opportunity II, LLC · CIK 0001935810 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 195,074

F1 · ownership.direct: The shares are owned directly by Atlas Venture Opportunity Fund II, L.P. ("AVOF II"). Atlas Venture Associates Opportunity II, L.P. ("AVAO II LP") is the general partner of AVOF II. Atlas Venture Associates Opportunity II, LLC ("AVAO II LLC") is the general partner of AVAO II LP. Each of AVAO II LP and AVAO II LLC disclaims beneficial ownership of the securities held by AVOF II, except to the extent of its pecuniary interest therein, if any.

SEC source: 0000950170-24-047680 · ownership.xml · nonDerivative · entry 1

Yang Rick · CIK 0001851328 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047686 · ownership.xml · nonDerivative · entry 1

New Enterprise Associates 17, L.P. · CIK 0001768564 · 10% owner

NEA Partners 17, L.P. · CIK 0001796820 · 10% owner

NEA 17 GP, LLC · CIK 0001796821 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.direct: The securities are directly held by New Enterprise Associates 17, L.P. ("NEA 17") and are indirectly held by NEA Partners 17, L.P. ("NEA Partners 17"), the sole general partner of NEA 17, NEA 17 GP, LLC ("NEA 17 GP"), the sole general partner of NEA Partners 17, and the individual managers of NEA 17 GP (NEA Partners 17, NEA 17 GP and the individual managers of NEA 17 GP (collectively, the "Managers") together, the "Indirect Reporting Persons"). The Mangers are Forest Baskett, Ali Behbahani, Carmen Chang, Anthony Florence, Jr., Mohamad Makhzoumi, Edward Mathers, Scott Sandell, Paul Walker and Rick Yang. The Indirect Reporting Persons disclaim beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Indirect Reporting Persons have no pecuniary interest.

SEC source: 0000950170-24-047678 · ownership.xml · nonDerivative · entry 1

SANDELL SCOTT D · CIK 0001237289 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047685 · ownership.xml · nonDerivative · entry 1

BASKETT FOREST · CIK 0001277631 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047681 · ownership.xml · nonDerivative · entry 1

Mathers Edward T · CIK 0001328625 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047683 · ownership.xml · nonDerivative · entry 1

Walker Paul Edward · CIK 0001553150 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047682 · ownership.xml · nonDerivative · entry 1

Florence Anthony A. Jr. · CIK 0001559827 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047684 · ownership.xml · nonDerivative · entry 1

Behbahani Ali · CIK 0001613867 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047679 · ownership.xml · nonDerivative · entry 1

Makhzoumi Mohamad · CIK 0001630226 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-24-047687 · ownership.xml · nonDerivative · entry 1

Chang Carmen · CIK 0001746342 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,090,793

F1 · kind: Acquired from the Issuer on April 22, 2024 pursuant to a Subscription Agreement dated April 17, 2024.

F2 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.

SEC source: 0000950170-23-066806 · ownership.xml · derivative · entry 1

Meyers Rachel · CIK 0002001472 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,551

Underlying: Common Stock · 12,551 shares

Expires 2033-11-26

F1 · derivative.exercise_date: The shares subject to the option vest in three equal annual installments commencing from November 27, 2023, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0000950170-23-066217 · ownership.xml · nonDerivative · entry 4

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,150

F1 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance restricted stock units, and does not represent a discretionary trade by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $38.62 to $39.015, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-23-066217 · ownership.xml · nonDerivative · entry 3

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,352

F1 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance restricted stock units, and does not represent a discretionary trade by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $37.52 to $38.35, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-23-066217 · ownership.xml · nonDerivative · entry 2

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,966

F1 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance restricted stock units, and does not represent a discretionary trade by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $36.40 to $37.20, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-23-066217 · ownership.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,196

F1 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance restricted stock units, and does not represent a discretionary trade by the Reporting Person.

F2 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $35.26 to $36.06, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 9

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,306

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 8

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,340

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F10 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $45.07 to $46.00, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 7

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,407

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F9 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $43.87 to $44.175, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 6

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,598

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F8 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $42.75 to $43.625, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 5

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,823

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F7 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $41.45 to $42.00, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 4

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,864

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F6 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $39.155 to $40.00, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-065866 · ownership.xml · nonDerivative · entry 3

Lucchino David L. · CIK 0001785288 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,237

F4 · shares: Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of RSUs, and does not represent a discretionary trade by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $37.575 to $37.955, inclusive. Full information regarding the number of shares sold at each separate price can be furnished to the Issuer, any security holder of the Issuer, or the SEC staff upon request.

F2 · balance_after: Total number of shares of common stock is adjusted for a 1-for-50 reverse stock split effected by the Issuer on November 3, 2023.

SEC source: 0000950170-23-060597 · ownership.xml · derivative · entry 3

FORMELA JEAN FRANCOIS · CIK 0001030575 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2033-11-02

F6 · derivative.exercise_date: The shares subject to the option vest in three equal annual installments commencing from November 3, 2023, subject to the Reporting Person's continued service on each such vesting date.

F7 · ownership.direct: The Reporting Person is a member of Atlas XI and is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the option to Atlas Venture Life Science Advisors, LLC. As such, the Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of his pecuniary interest therein, if any.

SEC source: 0000950170-23-060597 · ownership.xml · nonDerivative · entry 2

FORMELA JEAN FRANCOIS · CIK 0001030575 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 177,217

F4 · kind: Received in exchange for Legacy Korro common stock issued in the private placement completed immediately prior to the Merger.

F4 · shares: Received in exchange for Legacy Korro common stock issued in the private placement completed immediately prior to the Merger.

F4 · price: Received in exchange for Legacy Korro common stock issued in the private placement completed immediately prior to the Merger.

F5 · ownership.nature: These shares are held directly by Atlas Venture Opportunity Fund II, L.P. ("Atlas Opportunity II"). Atlas Venture Associates Opportunity II, L.P. ("Associates II") is the general partner of Atlas Opportunity II. Atlas Venture Associates Opportunity II, LLC ("Associates II LLC") is the general partner of Associates II. The Reporting Person is a member of Associates II LLC and disclaims Section 16 beneficial ownership of such shares, except to the extent of his pecuniary interest therein, if any.

SEC source: 0000950170-23-060597 · ownership.xml · nonDerivative · entry 1

FORMELA JEAN FRANCOIS · CIK 0001030575 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 942,075

F1 · kind: Received in exchange for (i) 3,000,000 shares of common stock, (ii) 4,000,000 shares of Series Seed 1 Preferred Stock, (iii) 2,000,000 shares of Series Seed 2 Preferred Stock, (iv) 1,538,462 shares of Series Seed 3 Preferred Stock, (v) 5,357,142 shares of Series A Preferred Stock and (vi) 3,064,273 shares of Series B Preferred Stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer.

F2 · kind: (Continued from Footnote 1) Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · shares: Received in exchange for (i) 3,000,000 shares of common stock, (ii) 4,000,000 shares of Series Seed 1 Preferred Stock, (iii) 2,000,000 shares of Series Seed 2 Preferred Stock, (iv) 1,538,462 shares of Series Seed 3 Preferred Stock, (v) 5,357,142 shares of Series A Preferred Stock and (vi) 3,064,273 shares of Series B Preferred Stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer.

F2 · shares: (Continued from Footnote 1) Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · price: Received in exchange for (i) 3,000,000 shares of common stock, (ii) 4,000,000 shares of Series Seed 1 Preferred Stock, (iii) 2,000,000 shares of Series Seed 2 Preferred Stock, (iv) 1,538,462 shares of Series Seed 3 Preferred Stock, (v) 5,357,142 shares of Series A Preferred Stock and (vi) 3,064,273 shares of Series B Preferred Stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer.

F2 · price: (Continued from Footnote 1) Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

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

SEC source: 0000950170-23-060608 · ownership.xml · derivative · entry 3

Bermingham Nessan · CIK 0001377759 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,712

Underlying: Common Stock · 24,712 shares

Expires 2033-02-08

F2 · derivative.exercise_price: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · kind: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · shares: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · price: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F6 · price: Received in exchange for a stock option to acquire 497,347 shares of Legacy Korro common stock issued under the 2019 Plan pursuant to the Merger Agreement.

F5 · derivative.exercise_date: The shares subject to the option vest in 48 equal monthly installments commencing from August 14, 2022, subject to the Reporting Person's continued service on each such vesting date.

F2 · derivative.underlying_shares: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

SEC source: 0000950170-23-060608 · ownership.xml · derivative · entry 2

Bermingham Nessan · CIK 0001377759 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 67,061

Underlying: Common Stock · 67,061 shares

Expires 2030-08-13

F2 · derivative.exercise_price: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · kind: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · shares: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F2 · price: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

F4 · price: Received in exchange for a stock option to acquire 1,349,645 shares of Legacy Korro common stock issued under the 2019 Plan pursuant to the Merger Agreement.

F3 · derivative.exercise_date: The shares subject to the option are fully vested and immediately exercisable.

F2 · derivative.underlying_shares: Upon the closing of the Merger, each outstanding option to purchase shares of Legacy Korro common stock issued under the Korro Bio, Inc. 2019 Stock Incentive Plan (the "2019 Plan") was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable under the 2019 Plan prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

SEC source: 0000950170-23-060608 · ownership.xml · nonDerivative · entry 1

Bermingham Nessan · CIK 0001377759 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,114

F1 · kind: Received in exchange for 706,702 shares of common stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · shares: Received in exchange for 706,702 shares of common stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · price: Received in exchange for 706,702 shares of common stock of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

SEC source: 0000950170-23-060599 · ownership.xml · derivative · entry 1

PEARSON TIMOTHY R · CIK 0001528617 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2033-11-02

F1 · derivative.exercise_date: The shares subject to the option vest in three equal annual installments commencing from November 3, 2023, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0001209191-23-054637 · doc4.xml · derivative · entry 2

Behbahani Ali · CIK 0001613867 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,000

Underlying: Common Stock · 16,000 shares

Expires 2033-11-02

F4 · derivative.exercise_date: The shares subject to the option vest in three equal annual installments commencing from November 3, 2023, subject to the Reporting Person's continued service on each such vesting date.

SEC source: 0001209191-23-054637 · doc4.xml · nonDerivative · entry 1

Behbahani Ali · CIK 0001613867 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 3

Disclosed balance after: 1,072,936

F1 · kind: Received in exchange for (i) 6,126,923 shares of Series Seed 3 Preferred Stock, (ii) 8,928,572 shares of Series A Preferred Stock, (iii) 1,532,567 shares of Series B-1 Preferred Stock, (iv) 1,438,849 shares of Series B-2 Preferred Stock and (v) shares of common stock issued in the private placement completed immediately prior to the Merger (as defined below) of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). [Continued in Footnote 2]

F2 · kind: [Continuation of Footnote 1] Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · shares: Received in exchange for (i) 6,126,923 shares of Series Seed 3 Preferred Stock, (ii) 8,928,572 shares of Series A Preferred Stock, (iii) 1,532,567 shares of Series B-1 Preferred Stock, (iv) 1,438,849 shares of Series B-2 Preferred Stock and (v) shares of common stock issued in the private placement completed immediately prior to the Merger (as defined below) of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). [Continued in Footnote 2]

F2 · shares: [Continuation of Footnote 1] Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F1 · price: Received in exchange for (i) 6,126,923 shares of Series Seed 3 Preferred Stock, (ii) 8,928,572 shares of Series A Preferred Stock, (iii) 1,532,567 shares of Series B-1 Preferred Stock, (iv) 1,438,849 shares of Series B-2 Preferred Stock and (v) shares of common stock issued in the private placement completed immediately prior to the Merger (as defined below) of Korro Bio Ops, Inc. (f/k/a Korro Bio, Inc., "Legacy Korro") pursuant to an Agreement and Plan of Merger dated as of July 14, 2023 (the "Merger Agreement") by and among Legacy Korro, the Issuer (f/k/a Frequency Therapeutics, Inc.) and Frequency Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). [Continued in Footnote 2]

F2 · price: [Continuation of Footnote 1] Under the terms of the Merger Agreement, on November 3, 2023, Merger Sub merged with and into Legacy Korro (the "Merger"), with Legacy Korro surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Legacy Korro common stock was converted into the right to receive 0.049688 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 1-for-50. Subsequent to the Merger, the name of the Issuer was changed from Frequency Therapeutics, Inc. to Korro Bio, Inc.

F3 · ownership.nature: The Reporting Person is a manager of NEA 17 GP, LLC, which is the sole general partner of NEA Partners 17, L.P. ("NEA Partners 17"). NEA Partners 17 is the sole general partner of New Enterprise Associates 17, L.P. ("NEA 17"), which is the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership, within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the securities held by NEA 17 in which the Reporting Person has no pecuniary interest.