Form 4
Open-market purchase
Insider Buying
2026-10-15
PRTA insider SCULLY WILLIAM P (10% Owner) bought 110,000 shares (~$920.0K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 110,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
100,000 |
$8.35 |
$835.5K |
P |
Open-market purchase
|
10,000 |
$8.46 |
$84.6K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 110,000
Est. Value: $920.0K
Form 4
Open-market purchase
Insider Buying
2026-10-09
PRTA insider SCULLY WILLIAM P (10% Owner) bought 215,000 shares (~$1.82M)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 215,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
125,000 |
$8.40 |
$1.05M |
P |
Open-market purchase
|
90,000 |
$8.57 |
$770.9K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 215,000
Est. Value: $1.82M
Form 4
Open-market purchase
Insider Buying
2026-10-06
PRTA insider SCULLY WILLIAM P (10% Owner) bought 100,000 shares (~$857.2K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 100,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
100,000 |
$8.57 |
$857.2K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 100,000
Est. Value: $857.2K
Form 4
Open-market purchase
Insider Buying
2026-09-30
PRTA insider SCULLY WILLIAM P (10% Owner) bought 162,000 shares (~$1.41M)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 162,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
162,000 |
$8.68 |
$1.41M |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 162,000
Est. Value: $1.41M
Form 4
Open-market purchase
Insider Buying
2026-09-29
PRTA insider SCULLY WILLIAM P (10% Owner) bought 103,500 shares (~$889.9K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 103,500 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
103,500 |
$8.60 |
$889.9K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 103,500
Est. Value: $889.9K
Form 4
Open-market purchase
Insider Buying
2026-09-21
PRTA insider SCULLY WILLIAM P (10% Owner) bought 100,000 shares (~$843.5K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 100,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
100,000 |
$8.43 |
$843.5K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 100,000
Est. Value: $843.5K
Form 4
Open-market purchase
Insider Buying
2026-09-03
PRTA insider SCULLY WILLIAM P (10% Owner) bought 27,000 shares (~$255.7K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 27,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
27,000 |
$9.47 |
$255.7K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 27,000
Est. Value: $255.7K
Form 4
Open-market purchase
Insider Buying
2026-08-21
PRTA insider SCULLY WILLIAM P (10% Owner) bought 50,000 shares (~$439.4K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 50,000 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
50,000 |
$8.79 |
$439.4K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 50,000
Est. Value: $439.4K
Form 4
Gift
Tax / Compensation Filing
2026-08-18
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
SCULLY WILLIAM P (10% Owner) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
Shares were transferred as a gift, typically for estate or charitable planning. No sale into the market took place.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
G |
Gift
|
336,000 |
— |
— |
G |
Gift
|
627,553 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 963,553
Form 4
Gift
Tax / Compensation Filing
2026-08-11
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
SCULLY WILLIAM P (10% Owner) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
Shares were transferred as a gift, typically for estate or charitable planning. No sale into the market took place.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
G |
Gift
|
251,553 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 251,553
Form 4
Open-market purchase
Insider Buying
2026-08-10
PRTA insider SCULLY WILLIAM P (10% Owner) bought 37,500 shares (~$323.2K)
SCULLY WILLIAM P, listed as 10% Owner at PROTHENA CORP PUBLIC LTD CO, reported an open-market purchase of 37,500 PRTA shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.
The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
P |
Open-market purchase
|
34,000 |
$8.62 |
$293.1K |
P |
Open-market purchase
|
3,500 |
$8.62 |
$30.2K |
Filing: Form 4 (Insider Transaction)
Insider: SCULLY WILLIAM P (10% Owner)
Shares: 37,500
Est. Value: $323.2K
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Zago Wagner M. (Chief Scientific Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
51,000 |
— |
— |
D |
Disposition to issuer
|
51,000 |
$8.56 |
$436.6K |
M |
Option exercise
derivative · Restricted Stock Units
|
51,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Zago Wagner M. (Chief Scientific Officer)
Shares: 102,000
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Walker Karin L (Chief Accounting Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
15,000 |
— |
— |
D |
Disposition to issuer
|
15,000 |
$8.56 |
$128.4K |
M |
Option exercise
derivative · Restricted Stock Units
|
15,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Walker Karin L (Chief Accounting Officer)
Shares: 30,000
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Swanson Chad J. (Chief Development Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
51,000 |
— |
— |
D |
Disposition to issuer
|
40,800 |
$8.56 |
$349.2K |
F |
Tax withholding on vested shares
|
3,467 |
$8.56 |
$29.7K |
M |
Option exercise
derivative · Restricted Stock Units
|
51,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Swanson Chad J. (Chief Development Officer)
Shares: 95,267
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Smith Brandon S. (Chief Operating Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
78,000 |
— |
— |
D |
Disposition to issuer
|
78,000 |
$8.56 |
$667.7K |
M |
Option exercise
derivative · Restricted Stock Units
|
78,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Smith Brandon S. (Chief Operating Officer)
Shares: 156,000
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Nguyen Tran (Chief Strategy Officer and CFO) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
57,000 |
— |
— |
D |
Disposition to issuer
|
57,000 |
$8.56 |
$487.9K |
M |
Option exercise
derivative · Restricted Stock Units
|
57,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Nguyen Tran (Chief Strategy Officer and CFO)
Shares: 114,000
Form 4
Option exercise
Tax / Compensation Filing
2026-07-30
PRTA insider Form 4 filed for equity award, exercise, or tax withholding
Kinney Gene G. (Director, President and CEO) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.
The insider converted options into shares. The exercise price was fixed when the options were granted, so the timing usually tracks an expiry schedule.
Transactions reported on this filing
| Code |
Nature |
Shares |
Price |
Value |
M |
Option exercise
|
84,000 |
— |
— |
D |
Disposition to issuer
|
84,000 |
$8.56 |
$719.0K |
M |
Option exercise
derivative · Restricted Stock Units
|
84,000 |
— |
— |
Filing: Form 4 (Insider Transaction)
Insider: Kinney Gene G. (Director, President and CEO)
Shares: 168,000