Carroll Jill

SEC source: 0001193125-26-201894 · ownership.xml · derivative · entry 5

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 0

Underlying: Common Stock · 489,486 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.

F3 · derivative.exercise_price: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F3 · price: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F3 · derivative.exercise_date: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F3 · derivative.expiration_date: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund II Aggregator, LP ("SR One Fund II Aggregator"). SR One Capital Partners II, LP ("SR One Partners II") serves as the general partner of SR One Fund II Aggregator, and SR One Capital Management, LLC serves as the general partner of SR One Partners II. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund II Aggregator, and a limited partner of SR One Partners II. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001193125-26-201894 · ownership.xml · derivative · entry 4

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 0

Underlying: Common Stock · 1,419,298 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: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F1 · price: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F1 · derivative.exercise_date: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F1 · derivative.expiration_date: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund II Aggregator, LP ("SR One Fund II Aggregator"). SR One Capital Partners II, LP ("SR One Partners II") serves as the general partner of SR One Fund II Aggregator, and SR One Capital Management, LLC serves as the general partner of SR One Partners II. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund II Aggregator, and a limited partner of SR One Partners II. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001193125-26-201894 · ownership.xml · nonDerivative · entry 3

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 2,186,562

F2 · ownership.nature: The securities are directly held by SR One Capital Fund II Aggregator, LP ("SR One Fund II Aggregator"). SR One Capital Partners II, LP ("SR One Partners II") serves as the general partner of SR One Fund II Aggregator, and SR One Capital Management, LLC serves as the general partner of SR One Partners II. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund II Aggregator, and a limited partner of SR One Partners II. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001193125-26-201894 · ownership.xml · nonDerivative · entry 2

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,908,784

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.

F3 · kind: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F3 · price: On May 1, 2026, each share of Series D Convertible Preferred Stock (the "Series D Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series D Preferred Stock had no expiration date.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund II Aggregator, LP ("SR One Fund II Aggregator"). SR One Capital Partners II, LP ("SR One Partners II") serves as the general partner of SR One Fund II Aggregator, and SR One Capital Management, LLC serves as the general partner of SR One Partners II. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund II Aggregator, and a limited partner of SR One Partners II. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001193125-26-201894 · ownership.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 1,419,298

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: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F1 · price: On May 1, 2026, each share of Series C-1 Convertible Preferred Stock (the "Series C-1 Preferred Stock") automatically converted into shares of Common Stock on a one-for-19.2417 basis without payment of further consideration immediately prior to the closing of the Issuer's initial public offering. The Series C-1 Preferred Stock had no expiration date.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund II Aggregator, LP ("SR One Fund II Aggregator"). SR One Capital Partners II, LP ("SR One Partners II") serves as the general partner of SR One Fund II Aggregator, and SR One Capital Management, LLC serves as the general partner of SR One Partners II. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund II Aggregator, and a limited partner of SR One Partners II. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001193125-26-188029 · ownership.xml · derivative · entry 4

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 9,174 shares

Expires 2035-05-29

F3 · price: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

F3 · derivative.exercise_date: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

SEC source: 0001193125-26-188029 · ownership.xml · derivative · entry 3

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,011 shares

Expires 2034-05-28

F3 · price: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

F3 · derivative.exercise_date: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

SEC source: 0001193125-26-188029 · ownership.xml · derivative · entry 2

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 11,459 shares

Expires 2033-06-14

F3 · price: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

F3 · derivative.exercise_date: Pursuant to the Merger Agreement, each outstanding option to purchase shares of Common Stock (a "Company Option"), whether or not vested, and which had a per share exercise price that was less than the Closing Amount, was canceled and converted into the right of the holder to receive (i) (subject to any applicable withholding taxes) a lump-sum cash payment equal to (x) the excess (if any) of (a) the Closing Amount over (b) the per share exercise price subject to such Company Option, multiplied by (y) the total number of shares subject to such Company Option immediately prior to the effective time of the Merger, and (ii) one (1) CVR for each share subject to such Company Option immediately prior to the effective time of the Merger.

SEC source: 0001193125-26-188029 · ownership.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 0

F1 · price: Pursuant to the Agreement and Plan of Merger, dated February 22, 2026 (the "Merger Agreement"), by and among Arcellx, Inc. ("Company"), Gilead Sciences, Inc. ("Parent"), and Ravens Sub, Inc., a wholly owned subsidiary of Parent ("Purchaser"), the shares of common stock of Company that were tendered to Purchaser prior to the expiration time of the offer were exchanged for (x) $115.00 per share ("Closing Amount"), net to the seller in cash, without interest, subject to withholding tax, plus (y) one contractual contingent value right (a "CVR"), which represents the right to receive one contingent payment of $5.00 per CVR in cash, without interest, and subject to any withholding tax, pursuant to the terms and subject to the conditions of a contingent value rights agreement. After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into Company (the "Merger"), with Company surviving the Merger as a wholly owned subsidiary of Parent.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator. The Reporting Person is a partner of SR One Capital Management, LP ("SR One Capital Management"), an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0000950170-25-079730 · ownership.xml · derivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,174

Underlying: Common Stock · 9,174 shares

Expires 2035-05-29

F1 · derivative.exercise_date: Subject to the reporting person's continuing to be a Service Provider (as defined in the 2022 Equity Incentive Plan) through such applicable vesting date, one hundred percent (100%) of the shares subject to the award will vest on the earlier to occur of May 29, 2026 or the next annual meeting of stockholders.

SEC source: 0000950170-24-069955 · ownership.xml · derivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,011

Underlying: Common Stock · 8,011 shares

Expires 2034-05-28

F1 · derivative.exercise_date: Subject to the reporting person's continuing to be a Service Provider (as defined in the 2022 Equity Incentive Plan) through such applicable vesting date, one hundred percent (100%) of the shares subject to the award will vest on the earlier to occur of May 28, 2025 or the next annual meeting of stockholders.

SEC source: 0000950170-24-036013 · ownership.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 1

Disclosed balance after: 1,479,148

F1 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-23-058974 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 1

Disclosed balance after: 1,983,411

F1 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator and SR One Capital Management, LLC serves as the general partner of SR One Partners I. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-23-037969 · doc4.xml · derivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,459

Underlying: Common Stock · 11,459 shares

Expires 2033-06-14

F1 · derivative.exercise_date: Subject to the reporting person's continuing to be a Service Provider (as defined in the 2022 Equity Incentive Plan) through such applicable vesting date, one hundred percent (100%) of the shares subject to the award will vest on the earlier to occur of June 14, 2024 or the next annual meeting of stockholders.

SEC source: 0001209191-23-033867 · doc4.xml · nonDerivative · entry 2

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 1

Disclosed balance after: 2,487,674

F2 · price: The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.25 to $44.675 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

F1 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator and SR One Capital Management, LLC serves as the general partner of SR One Partners I. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-23-033867 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 1

Disclosed balance after: 2,513,230

F1 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator and SR One Capital Management, LLC serves as the general partner of SR One Partners I. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-23-029613 · doc4.xml · nonDerivative · entry 2

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 2,828,394

F3 · price: The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $46.00 to $46.56 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator and SR One Capital Management, LLC serves as the general partner of SR One Partners I. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-23-029613 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · See Note 2

Disclosed balance after: 2,834,879

F1 · price: The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $45.00 to $45.745 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

F2 · ownership.nature: The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") serves as the general partner of SR One Fund I Aggregator and SR One Capital Management, LLC serves as the general partner of SR One Partners I. The Reporting Person is a partner of SR One Capital Management, LP, an entity affiliated with SR One Fund I Aggregator, and a limited partner of SR One Partners I. The Reporting Person disclaims beneficial ownership of these securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose.

SEC source: 0001209191-22-008157 · doc4.xml · derivative · entry 9

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 433,196 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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · price: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.exercise_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.expiration_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F4 · ownership.nature: Shares directly held by by SR One Co-Invest II, LLC. SR One Co-Invest Manager II, LLC serves as the manager of SR Co-Invest II, LLC, and SR One Capital Management, LLC serves as the managing member of SR Co-Invest Manager II, LLC. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Co-Invest II, LLC and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting person disclaims beneficial ownership of the shares held of record by SR One Co-Invest II, LLC except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · derivative · entry 8

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 649,795 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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · price: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.exercise_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.expiration_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · derivative · entry 7

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 533,389 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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · price: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.exercise_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.expiration_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · derivative · entry 6

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 666,651 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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · price: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.exercise_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.expiration_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · derivative · entry 5

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 1,550,309 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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · price: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.exercise_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F1 · derivative.expiration_date: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · nonDerivative · entry 4

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 2,033,196

F5 · shares: SR One Co-Invest II, LLC purchased 1,600,000 shares of Common Stock of the Issuer in connection with the Issuer's public offering.

F4 · ownership.nature: Shares directly held by by SR One Co-Invest II, LLC. SR One Co-Invest Manager II, LLC serves as the manager of SR Co-Invest II, LLC, and SR One Capital Management, LLC serves as the managing member of SR Co-Invest Manager II, LLC. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Co-Invest II, LLC and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting person disclaims beneficial ownership of the shares held of record by SR One Co-Invest II, LLC except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · nonDerivative · entry 3

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 433,196

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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F4 · ownership.nature: Shares directly held by by SR One Co-Invest II, LLC. SR One Co-Invest Manager II, LLC serves as the manager of SR Co-Invest II, LLC, and SR One Capital Management, LLC serves as the managing member of SR Co-Invest Manager II, LLC. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Co-Invest II, LLC and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting person disclaims beneficial ownership of the shares held of record by SR One Co-Invest II, LLC except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · nonDerivative · entry 2

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 3,466,811

F3 · shares: SR One Capital Fund I Aggregator, LP purchased 66,667 shares of Common Stock of the Issuer in connection with the Issuer's public offering.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0001209191-22-008157 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 3,400,144

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: All shares of Series A Preferred Stock, par value $0.001 per share, Series B-1 Preferred Stock, par value $0.001 per share, Series B-2 Preferred Stock, par value $0.001 per share, and Series C Preferred Stock, par value $0.001 per share, of the Issuer automatically converted on a one-for-one basis to shares of the Issuer's common stock, par value $0.001 per share ("Common Stock") immediately prior to the closing of the Issuer's initial public offering of its Common Stock, and have no expiration date.

F2 · ownership.nature: Shares directly held by SR One Capital Fund I Aggregator, L.P. SR One Capital Partners I, LP serves as the general partner of SR One Capital Fund I Aggregator, LP and SR One Capital Management, LLC serves as the general partner of SR One Capital Partners I, LP. The Reporting Person, a member of the Issuer's board of directors, is a partner of SR One Capital Management, LP, an entity affiliated with SR One Capital Fund I Aggregator, L.P. and, therefore, may be deemed to have a pecuniary interest over these shares. The Reporting Person disclaims beneficial ownership of the shares held of record by SR One Capital Fund I Aggregator, L.P. except to the extent of her pecuniary interest therein.

SEC source: 0000899243-21-014441 · doc4.xml · derivative · entry 2

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 13,997 shares

Expires 2030-07-16

F4 · price: Disposed of pursuant to the Merger Agreement in exchange for the excess of the Offer Price over the exercise price of the option.

F3 · derivative.exercise_date: All options were vested and exercisable as of immediately prior to the Effective Time.

SEC source: 0000899243-21-014441 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 0

F1 · kind: Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated February 24, 2021, among Pandion Therapeutics, Inc. (the "Company"), Merck Sharp & Dohme Corp. ("Merck") and Panama Merger Sub, Inc. ("Merger Sub"), Merger Sub commenced a tender offer (the "Offer") to purchase all outstanding Company common stock for the price of $60.00 per share in cash (the "Offer Price"). On April 1, 2021, the Offer consummated, after which Merger Sub merged with and into the Company (the "Merger") and the Company became a wholly owned subsidiary of Merck. At the consummation of the Offer and the Merger, respectively, (i) Merger Sub purchased all shares of Company common stock that were validly tendered pursuant to the Offer for a cash payment equal to the Offer Price and (ii) all shares of Company common stock outstanding immediately prior to the effective time of the Merger (the "Effective Time"), were cancelled and converted automatically into the right to receive the Offer Price.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc. As Principal at S.R. One, Limited and an employee of GlaxoSmithKline LLC, Ms. Carroll disclaims beneficial ownership of all the shares held by S.R. One, Limited and this report shall not be deemed an admission of beneficial ownership of such shares for the purposes of Section 16 or for any other purpose except to the extent of her pecuniary interest therein.

SEC source: 0000899243-20-019891 · doc4.xml · derivative · entry 5

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 348,469 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.

F3 · derivative.exercise_price: The Series B Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series B Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F3 · price: The Series B Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series B Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F3 · derivative.exercise_date: The Series B Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series B Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F3 · derivative.expiration_date: The Series B Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series B Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").

SEC source: 0000899243-20-019891 · doc4.xml · derivative · entry 4

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 0

Underlying: Common Stock · 1,538,724 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 Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series A Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F1 · price: The Series A Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series A Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F1 · derivative.exercise_date: The Series A Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series A Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F1 · derivative.expiration_date: The Series A Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series A Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").

SEC source: 0000899243-20-019891 · doc4.xml · nonDerivative · entry 3

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 2,248,304

F4 · shares: S.R. One, Limited purchased 361,111 shares of Common Stock of Pandion Therapeutics, Inc. (the "Issuer") in connection with the Issuer's public offering.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").

SEC source: 0000899243-20-019891 · doc4.xml · nonDerivative · entry 2

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,887,193

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.

F3 · price: The Series B Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series B Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").

SEC source: 0000899243-20-019891 · doc4.xml · nonDerivative · entry 1

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 1,538,724

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 Preferred Stock were convertible at a conversion rate equal to one share of Common Stock per 5.0994 shares of Series A Preferred Stock at any time at the option of the holder and were automatically converted upon the closing of the Issuer's initial public offering. The shares had no expiration date.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").

SEC source: 0000899243-20-019891 · doc4.xml · derivative · entry 6

Carroll Jill · CIK 0001598542 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 13,997

Underlying: Common Stock · 13,997 shares

Expires 2030-07-16

F5 · derivative.exercise_date: The stock option was granted to Jill A. Carroll as director's compensation with the shares vesting with respect to 2.7778% of the shares at the end of each successive one month period following the grant date until the third anniversary of the grant date, subject to Ms. Carroll's continued service on each applicable veting date. As Principal at S.R. One, Limited and an employee of GlaxoSmithKline LLC, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc., Ms. Carroll disclaims beneficial ownership of all the shares held by S.R. One, Limited and this report shall not be deemed an admission of beneficial ownership of such shares for the purposes of Section 16 or for any other purpose except to the extent of her pecuniary interest therein.

F2 · ownership.nature: The shares reported herein are held of record by S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc (the "Reporting Person").