PRTA

SEC source: 0001045463-26-000020 · primary_doc.xml · nonDerivative · entry 2

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 529,000

F2 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.4000 to $8.8063, inclusive.

SEC source: 0001045463-26-000020 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 439,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.2100 to $8.6000, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (1) and (2) to this Form 4.

SEC source: 0001045463-26-000019 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 314,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.5150 to $8.6098, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of ProthenaCorp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000018 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 214,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.6000 to $8.7550, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000017 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Manatee Equity Fund LLC

Disclosed balance after: 187,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.1582 to $8.8500, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

F2 · ownership.nature: The reporting person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.

SEC source: 0001045463-26-000016 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 927,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.3350 to $8.4829, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000015 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 827,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.4072 to $9.6100, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000014 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 800,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.7497 to $8.9000, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000013 · primary_doc.xml · nonDerivative · entry 2

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 750,000

SEC source: 0001045463-26-000013 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,377,553

SEC source: 0001045463-26-000011 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,041,553

SEC source: 0001045463-26-000010 · primary_doc.xml · nonDerivative · entry 2

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · By Manatee Equity Fund LLC

Disclosed balance after: 83,500

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.5094 to $8.7500, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

F2 · ownership.nature: The reporting person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.

SEC source: 0001045463-26-000010 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 790,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.5094 to $8.7500, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0000905148-26-003410 · form4.xml · nonDerivative · entry 2

Kingston Anne Evans · CIK 0002127851 · Chief Strategy Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 55,782

F1 · kind: The transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on March 30, 2026.

F2 · price: The transaction was executed in multiple trades in prices ranging from $8.40 to $8.64, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the ranges set forth in this footnote.

SEC source: 0000905148-26-003409 · form4.xml · nonDerivative · entry 2

Isaacs Michael John · CIK 0002127815 · General Counsel & Company Sec.

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 35,745

F1 · kind: The transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on April 3, 2026.

F2 · price: The transaction was executed in multiple trades in prices ranging from $8.40 to $8.65, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

SEC source: 0000905148-26-003415 · form4.xml · derivative · entry 4

Swanson Chad J. · CIK 0002038509 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 51,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 85,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 85,000 RSUs reported in Table I (34,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 85,000 RSUs reported in Table I (34,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003415 · form4.xml · nonDerivative · entry 3

Swanson Chad J. · CIK 0002038509 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,733

SEC source: 0000905148-26-003415 · form4.xml · nonDerivative · entry 2

Swanson Chad J. · CIK 0002038509 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 44,200

SEC source: 0000905148-26-003415 · form4.xml · nonDerivative · entry 1

Swanson Chad J. · CIK 0002038509 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 85,000

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003414 · form4.xml · derivative · entry 3

Smith Brandon S. · CIK 0001805226 · Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 78,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 130,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 130,000 RSUs reported in Table I (52,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 130,000 RSUs reported in Table I (52,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003414 · form4.xml · nonDerivative · entry 2

Smith Brandon S. · CIK 0001805226 · Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 52,000

SEC source: 0000905148-26-003414 · form4.xml · nonDerivative · entry 1

Smith Brandon S. · CIK 0001805226 · Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 130,000

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003417 · form4.xml · derivative · entry 3

Zago Wagner M. · CIK 0001708681 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 51,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 85,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 85,000 RSUs reported in Table I (34,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 85,000 RSUs reported in Table I (34,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003417 · form4.xml · nonDerivative · entry 2

Zago Wagner M. · CIK 0001708681 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,000

SEC source: 0000905148-26-003417 · form4.xml · nonDerivative · entry 1

Zago Wagner M. · CIK 0001708681 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 85,000

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003413 · form4.xml · derivative · entry 3

Nguyen Tran · CIK 0001457013 · Chief Strategy Officer and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 57,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 95,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 95,000 RSUs reported in Table I (38,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 95,000 RSUs reported in Table I (38,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003413 · form4.xml · nonDerivative · entry 2

Nguyen Tran · CIK 0001457013 · Chief Strategy Officer and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,205

SEC source: 0000905148-26-003413 · form4.xml · nonDerivative · entry 1

Nguyen Tran · CIK 0001457013 · Chief Strategy Officer and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 97,205

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003416 · form4.xml · derivative · entry 3

Walker Karin L · CIK 0001559422 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 15,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 25,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 25,000 RSUs reported in Table I (10,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 25,000 RSUs reported in Table I (10,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003416 · form4.xml · nonDerivative · entry 2

Walker Karin L · CIK 0001559422 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,000

SEC source: 0000905148-26-003416 · form4.xml · nonDerivative · entry 1

Walker Karin L · CIK 0001559422 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 25,000

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003412 · form4.xml · derivative · entry 3

Kinney Gene G. · CIK 0001564380 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 84,000 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.

F2 · security: These RSUs reported in Table II were granted to the Reporting Person on July 28, 2025 as part of an aggregate award of 140,000 RSUs and initially reported in Table I of the Form 4 filed on July 30, 2025, because they were solely settleable in shares at the time of grant. These RSUs are being moved to Table II as of this Form 4.

F1 · derivative.exercise_price: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

F3 · derivative.exercise_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 140,000 RSUs reported in Table I (56,000 RSUs) are subject to vesting.

F3 · derivative.expiration_date: These RSUs reported in Table II are fully vested as of July 28, 2026 (the one-year anniversary of the grant date). The remainder of the 140,000 RSUs reported in Table I (56,000 RSUs) are subject to vesting.

SEC source: 0000905148-26-003412 · form4.xml · nonDerivative · entry 2

Kinney Gene G. · CIK 0001564380 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 68,793

SEC source: 0000905148-26-003412 · form4.xml · nonDerivative · entry 1

Kinney Gene G. · CIK 0001564380 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 152,793

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: Each restricted stock unit ("RSU") represents the contingent right to receive one share of the Issuer's Ordinary Shares upon vesting.

SEC source: 0000905148-26-003410 · form4.xml · nonDerivative · entry 1

Kingston Anne Evans · CIK 0002127851 · Chief Strategy Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 63,444

SEC source: 0000905148-26-003409 · form4.xml · nonDerivative · entry 1

Isaacs Michael John · CIK 0002127815 · General Counsel & Company Sec.

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 44,131

SEC source: 0001045463-26-000009 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 756,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $7.8600 to $7.9312, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000008 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 736,000

SEC source: 0001045463-26-000007 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,061,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $7.8400 to $8.4300, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000006 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 936,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.1000 to $9.4097, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000005 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 886,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.2323 to $9.4892, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0001045463-26-000004 · primary_doc.xml · nonDerivative · entry 1

SCULLY WILLIAM P · CIK 0001045463 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 836,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.5499 to $9.9750, inclusive. The reporting person undertakes to provide to Prothena Corp Public Ltd Co, any security holder of Prothena Corp Public Ltd Co, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (1) to this Form 4.

SEC source: 0000905148-26-002466 · form4.xml · derivative · entry 1

COLLIER RICHARD T · CIK 0001110751 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-002471 · form4.xml · derivative · entry 1

WELCH DANIEL G · CIK 0001206199 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-002469 · form4.xml · derivative · entry 1

Ekman Lars · CIK 0001376117 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-002467 · form4.xml · derivative · entry 1

Cooke Shane · CIK 0001524823 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-002470 · form4.xml · derivative · entry 1

Selkoe Dennis J. · CIK 0001582306 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-002468 · form4.xml · derivative · entry 1

Dunn William H. Jr. · CIK 0001977655 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,000

Underlying: Ordinary Shares · 27,000 shares

Expires 2036-05-15

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of the first anniversary of the grant date or the day of the annual general meeting in 2027 of the Issuer's shareholders, assuming continuous service as a director until such vesting date.

SEC source: 0000905148-26-001653 · form4.xml · derivative · entry 1

Kingston Anne Evans · CIK 0002127851 · Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Ordinary Shares · 100,000 shares

Expires 2036-04-10

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 25% of the total number of shares subject to the option on April 10, 2027, and with respect to 1/48th of the total number of shares subject to the option in successive, equal monthly installments on each monthly anniversary thereafter, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.

SEC source: 0000905148-26-001180 · form4.xml · derivative · entry 1

Swanson Chad J. · CIK 0002038509 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 190,000

Underlying: Ordinary Shares · 190,000 shares

Expires 2036-03-03

F1 · derivative.exercise_date: The shares subject to the option will vest and become exercisable as to 25% of the total number of shares subject to the option on March 3, 2027, and with respect to 1/48th of the total number of shares subject to the option in successive, equal monthly installments on each monthly anniversary thereafter, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.