FHTX

SEC source: 0001562180-21-004483 · primarydocument.xml · derivative · entry 1

SMITH IAN F · CIK 0001197032 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,530

Underlying: Common Stock · 12,530 shares

Expires 2031-06-22

F1 · derivative.exercise_date: The option was granted pursuant to a consulting agreement effective June 23, 2021 (the "Effective Date"). The option will vest as to 1/12 of the underlying shares of common stock on the first day of each month beginning on August 1, 2021, with the balance of then-unvested shares to vest one year after the Effective Date.

SEC source: 0001562180-21-003018 · primarydocument.xml · derivative · entry 1

SMITH IAN F · CIK 0001197032 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,060

Underlying: Common Stock · 25,060 shares

Expires 2031-04-26

F1 · derivative.exercise_date: The options will vest as to 25% of the underlying shares of common stock on April 27, 2022, the first anniversary of the vesting commencement date, and at a rate of 6.25% of the underlying shares thereafter on the first day of each calendar quarter following such first anniversary until the option is fully vested.

SEC source: 0000899243-21-003968 · doc4.xml · derivative · entry 1

Agresta Samuel · CIK 0001748961 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 100,000 shares

Expires 2031-01-27

F1 · derivative.exercise_date: The options will vest as to 25% of the underlying shares of common stock on January 28, 2022, the first anniversary of the vesting commencement date, and at a rate of 6.25% of the underlying shares thereafter on the first day of each calendar quarter following such first anniversary until the option is fully vested.

SEC source: 0000899243-21-003967 · doc4.xml · derivative · entry 1

Reine Allan · CIK 0001714023 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 120,000

Underlying: Common Stock · 120,000 shares

Expires 2031-01-27

F1 · derivative.exercise_date: The options will vest as to 25% of the underlying shares of common stock on January 28, 2022, the first anniversary of the vesting commencement date, and at a rate of 6.25% of the underlying shares thereafter on the first day of each calendar quarter following such first anniversary until the option is fully vested.

SEC source: 0000899243-21-003963 · doc4.xml · derivative · entry 1

GOTTSCHALK ADRIAN · CIK 0001828724 · Director · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 300,000

Underlying: Common Stock · 300,000 shares

Expires 2031-01-27

F1 · derivative.exercise_date: The options will vest as to 25% of the underlying shares of common stock on January 28, 2022, the first anniversary of the vesting commencement date, and at a rate of 6.25% of the underlying shares thereafter on the first day of each calendar quarter following such first anniversary until the option is fully vested.

SEC source: 0000899243-21-003977 · doc4.xml · derivative · entry 1

DECICCO CARL · CIK 0001828727 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 100,000 shares

Expires 2031-01-27

F1 · derivative.exercise_date: The options will vest as to 25% of the underlying shares of common stock on January 28, 2022, the first anniversary of the vesting commencement date, and at a rate of 6.25% of the underlying shares thereafter on the first day of each calendar quarter following such first anniversary until the option is fully vested.

SEC source: 0000899243-20-031581 · doc4.xml · derivative · entry 1

LaCascia Michael · CIK 0001831755 · Chief Legal Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 162,162

Underlying: Common Stock · 162,162 shares

Expires 2030-11-16

F1 · derivative.exercise_date: 25% of the shares underlying the stock option shall vest on November 9, 2021, with the remainder vesting in 12 substantially equal quarterly installments thereafter, subject to the Reporting Person's continued service with the Issuer through such applicable vesting dates.

SEC source: 0001140361-20-023907 · form4.xml · derivative · entry 3

Abu Dhabi Investment Authority · CIK 0001362558 · Former 10% Owner

Platinum International Investment Holding RSC Ltd · CIK 0001790748 · Former 10% Owner

Platinum Falcon B 2018 RSC Ltd · CIK 0001790749 · Former 10% Owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,081,081 shares

Expires not disclosed

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_price: Upon the closing of the sale of shares of Common Stock of the Issuer to the public in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $35,000,000 of gross proceeds to the Issuer, the Series B Preferred Stock converted automatically into Common Stock. Every 1.85 shares of Series B Preferred Stock converted into one share of Common Stock. There was no expiration date for the Series B Preferred Stock.

F1 · price: Upon the closing of the sale of shares of Common Stock of the Issuer to the public in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $35,000,000 of gross proceeds to the Issuer, the Series B Preferred Stock converted automatically into Common Stock. Every 1.85 shares of Series B Preferred Stock converted into one share of Common Stock. There was no expiration date for the Series B Preferred Stock.

F1 · derivative.exercise_date: Upon the closing of the sale of shares of Common Stock of the Issuer to the public in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $35,000,000 of gross proceeds to the Issuer, the Series B Preferred Stock converted automatically into Common Stock. Every 1.85 shares of Series B Preferred Stock converted into one share of Common Stock. There was no expiration date for the Series B Preferred Stock.

F1 · derivative.expiration_date: Upon the closing of the sale of shares of Common Stock of the Issuer to the public in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $35,000,000 of gross proceeds to the Issuer, the Series B Preferred Stock converted automatically into Common Stock. Every 1.85 shares of Series B Preferred Stock converted into one share of Common Stock. There was no expiration date for the Series B Preferred Stock.

F2 · ownership.direct: Platinum Falcon B 2018 RSC Limited ("Platinum Falcon") directly holds the Series B Preferred Stock and the shares of Common Stock received upon conversion of the Series B Preferred Stock. Platinum International Investment Holding RSC Limited ("Platinum Holdings") is the sole owner of Platinum Falcon, and the Abu Dhabi Investment Authority ("ADIA" and, together with Platinum Falcon and Platinum Holdings, the "Reporting Persons") is the sole owner of Platinum Holdings. Therefore, Platinum Holdings and ADIA may also be deemed to beneficially own the Series B Preferred Stock and the shares of Common Stock received upon conversion of the Series B Preferred Stock.

SEC source: 0001140361-20-023907 · form4.xml · nonDerivative · entry 2

Abu Dhabi Investment Authority · CIK 0001362558 · Former 10% Owner

Platinum International Investment Holding RSC Ltd · CIK 0001790748 · Former 10% Owner

Platinum Falcon B 2018 RSC Ltd · CIK 0001790749 · Former 10% Owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,231,081

F3 · ownership.direct: Platinum Falcon directly acquired 143,540 shares of Common Stock. Platinum Holdings and ADIA may also be deemed to beneficially own such shares of Common Stock. ADIA acquired directly 6,460 shares of Common Stock, and Platinum Holdings and Platinum Falcon disclaim beneficial ownership of such shares.

SEC source: 0001140361-20-023907 · form4.xml · nonDerivative · entry 1

Abu Dhabi Investment Authority · CIK 0001362558 · Former 10% Owner

Platinum International Investment Holding RSC Ltd · CIK 0001790748 · Former 10% Owner

Platinum Falcon B 2018 RSC Ltd · CIK 0001790749 · Former 10% Owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,081,081

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 · price: Upon the closing of the sale of shares of Common Stock of the Issuer to the public in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $35,000,000 of gross proceeds to the Issuer, the Series B Preferred Stock converted automatically into Common Stock. Every 1.85 shares of Series B Preferred Stock converted into one share of Common Stock. There was no expiration date for the Series B Preferred Stock.

F2 · ownership.direct: Platinum Falcon B 2018 RSC Limited ("Platinum Falcon") directly holds the Series B Preferred Stock and the shares of Common Stock received upon conversion of the Series B Preferred Stock. Platinum International Investment Holding RSC Limited ("Platinum Holdings") is the sole owner of Platinum Falcon, and the Abu Dhabi Investment Authority ("ADIA" and, together with Platinum Falcon and Platinum Holdings, the "Reporting Persons") is the sole owner of Platinum Holdings. Therefore, Platinum Holdings and ADIA may also be deemed to beneficially own the Series B Preferred Stock and the shares of Common Stock received upon conversion of the Series B Preferred Stock.

SEC source: 0000899243-20-029693 · doc4.xml · derivative · entry 13

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 1,801,801 shares

Expires not disclosed

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_price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F4 · ownership.nature: Shares held by Flagship Pioneering Special Opportunities Fund II, L.P. ("Flagship Opportunities Fund II"). Flagship Pioneering Special Opportunities Fund II General Partner LLC ("Opportunities Fund II GP") is the general partner of Flagship Opportunities Fund II. Flagship Pioneering, Inc. ("Flagship Pioneering") is the manager of Opportunities Fund II GP. Noubar B. Afeyan, Ph.D. is sole director of Flagship Pioneering. Each of Noubar B. Afeyan Ph.D., Flagship Pioneering, and Opportunities Fund II GP disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · derivative · entry 12

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 1,441,441 shares

Expires not disclosed

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_price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F3 · ownership.nature: Shares held by Flagship Ventures Opportunities Fund I, L.P. ("Flagship Opportunities Fund I"). Flagship Ventures Opportunities Fund I General Partner LLC ("Opportunities Fund I GP") is the general partner of Flagship Opportunities Fund I. Noubar B. Afeyan Ph.D. serves as the sole manager of Opportunities Fund I GP. Each of Opportunities Fund I GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · derivative · entry 11

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 722,320 shares

Expires not disclosed

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_price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · derivative · entry 10

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 4,504,504 shares

Expires not disclosed

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_price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · derivative · entry 9

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 4,054,054 shares

Expires not disclosed

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_price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 8

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,851,801

F4 · ownership.nature: Shares held by Flagship Pioneering Special Opportunities Fund II, L.P. ("Flagship Opportunities Fund II"). Flagship Pioneering Special Opportunities Fund II General Partner LLC ("Opportunities Fund II GP") is the general partner of Flagship Opportunities Fund II. Flagship Pioneering, Inc. ("Flagship Pioneering") is the manager of Opportunities Fund II GP. Noubar B. Afeyan, Ph.D. is sole director of Flagship Pioneering. Each of Noubar B. Afeyan Ph.D., Flagship Pioneering, and Opportunities Fund II GP disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 7

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,801,801

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 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F4 · ownership.nature: Shares held by Flagship Pioneering Special Opportunities Fund II, L.P. ("Flagship Opportunities Fund II"). Flagship Pioneering Special Opportunities Fund II General Partner LLC ("Opportunities Fund II GP") is the general partner of Flagship Opportunities Fund II. Flagship Pioneering, Inc. ("Flagship Pioneering") is the manager of Opportunities Fund II GP. Noubar B. Afeyan, Ph.D. is sole director of Flagship Pioneering. Each of Noubar B. Afeyan Ph.D., Flagship Pioneering, and Opportunities Fund II GP disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 6

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,491,441

F3 · ownership.nature: Shares held by Flagship Ventures Opportunities Fund I, L.P. ("Flagship Opportunities Fund I"). Flagship Ventures Opportunities Fund I General Partner LLC ("Opportunities Fund I GP") is the general partner of Flagship Opportunities Fund I. Noubar B. Afeyan Ph.D. serves as the sole manager of Opportunities Fund I GP. Each of Opportunities Fund I GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 5

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,441,441

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 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F3 · ownership.nature: Shares held by Flagship Ventures Opportunities Fund I, L.P. ("Flagship Opportunities Fund I"). Flagship Ventures Opportunities Fund I General Partner LLC ("Opportunities Fund I GP") is the general partner of Flagship Opportunities Fund I. Noubar B. Afeyan Ph.D. serves as the sole manager of Opportunities Fund I GP. Each of Opportunities Fund I GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 4

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 9,330,878

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 3

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 9,280,878

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 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 2

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 8,558,558

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 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029693 · doc4.xml · nonDerivative · entry 1

Flagship Ventures Fund V General Partner LLC · CIK 0001724575 · 10% owner

Flagship Ventures Opportunities Fund I General Partner LLC · CIK 0001725004 · 10% owner

Flagship Pioneering Special Opportunities Fund II General Partner LLC · CIK 0001826217 · 10% owner

Flagship Ventures Fund V, L.P. · CIK 0001627639 · 10% owner

Flagship Ventures Opportunities Fund I, L.P. · CIK 0001677345 · 10% owner

Flagship Pioneering Special Opportunities Fund II, L.P. · CIK 0001761283 · 10% owner

Flagship Pioneering Inc. · CIK 0001400240 · 10% owner

AFEYAN NOUBAR · CIK 0001222012 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 4,054,054

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 · price: The Series A-1 Convertible Preferred Stock, Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II, column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by Flagship Ventures Fund V, L.P. ("Flagship Fund V"). Flagship Ventures Fund V General Partner LLC ("Fund V GP") is the general partner of Flagship Fund V. Noubar B. Afeyan Ph.D. serves as the sole manager of Fund V GP. Each of Fund V GP and Noubar B. Afeyan Ph.D. disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein.

SEC source: 0000899243-20-029696 · doc4.xml · nonDerivative · entry 1

DECICCO CARL · CIK 0001828727 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 258,397

SEC source: 0000899243-20-029694 · doc4.xml · derivative · entry 3

GOTTSCHALK ADRIAN · CIK 0001828724 · Director · See Remarks

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 7,207 shares

Expires not disclosed

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_price: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by the Adrian H. Gottschalk Living Trust dated September 8, 2009, of which the Reporting Person is the trustee.

SEC source: 0000899243-20-029694 · doc4.xml · derivative · entry 2

GOTTSCHALK ADRIAN · CIK 0001828724 · Director · See Remarks

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 18,018 shares

Expires not disclosed

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_price: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · price: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.exercise_date: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F1 · derivative.expiration_date: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by the Adrian H. Gottschalk Living Trust dated September 8, 2009, of which the Reporting Person is the trustee.

SEC source: 0000899243-20-029694 · doc4.xml · nonDerivative · entry 1

GOTTSCHALK ADRIAN · CIK 0001828724 · Director · See Remarks

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 25,225

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 · price: The Series A-2 Convertible Preferred Stock, and Series B Convertible Preferred Stock (collectively, the "Preferred Stock") is convertible into the number of shares of the Registrant's common stock shown in Table II column 7 and has no expiration date. The Preferred Stock automatically converted into common stock upon the closing of the Registrant's initial public offering, which occurred on October 27, 2020.

F2 · ownership.nature: Shares held by the Adrian H. Gottschalk Living Trust dated September 8, 2009, of which the Reporting Person is the trustee.