StockCIK 1559053

PROTHENA CORP PUBLIC LTD CO (PRTA): Insider Trades and Fund Holdings

In the past 12 months, PROTHENA CORP PUBLIC LTD CO insiders reported 12 open-market purchases worth $8.65M and 0 sales worth $0.

12Insider buys, 12 months

$8.65MBought by insiders, 12 months

$0Sold by insiders, 12 months

1Tracked funds holding

Recent insider trades

Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 26, 2026.

Recent PRTA insider trades
Filed	Traded	Insider	Role	Type	Shares	Price ($)	Value	Holding	Filing
Oct 26	Oct 22	William P. Scully10% owner	10% owner	▲ BUY	100,000	8.19	$819K	+9.6%	Form 4 ↗
Oct 26	Oct 23	William P. Scully10% owner	10% owner	▲ BUY	50,000	8.07	$404K	+4.4%	Form 4 ↗
Oct 15	Oct 13	William P. Scully10% owner	10% owner	▲ BUY	100,000	8.35	$835K	+11%	Form 4 ↗
Oct 15	Oct 14	William P. Scully10% owner	10% owner	▲ BUY	10,000	8.46	$85K	+1.0%	Form 4 ↗
Oct 9	Oct 7	William P. Scully10% owner	10% owner (ind.)	▲ BUY	125,000	8.40	$1.05M	+40%	Form 4 ↗
Oct 9	Oct 8	William P. Scully10% owner	10% owner (ind.)	▲ BUY	90,000	8.57	$771K	+21%	Form 4 ↗
Oct 6	Oct 2	William P. Scully10% owner	10% owner (ind.)	▲ BUY	100,000	8.57	$857K	+47%	Form 4 ↗
Sep 30	Sep 29	William P. Scully10% owner	10% owner (ind.)	▲ BUY	162,000	8.68	$1.41M	+312%	Form 4 ↗
Sep 29	Sep 28	William P. Scully10% owner	10% owner (ind.)	▲ BUY	103,500	8.60	$890K	+124%	Form 4 ↗
Sep 21	Sep 18	William P. Scully10% owner	10% owner	▲ BUY	100,000	8.43	$843K	+12%	Form 4 ↗

Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings

All 12 PRTA insider trades →

Insiders who traded in the past year

Insider	Role	Buys	Bought	Sells	Sold	Latest
William P. Scully	10% owner	12	$8.65M	0	$0	Oct 26, 2026

Tracked funds that report PRTA

From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.

Fund	Quarter	Shares	Value	% of portfolio	Change
Renaissance Technologies	Q2 2026	697,615	$6.83M	0.01%	▲ +14.8%

Source: SEC Form 13F-HR filings, retrieved Oct 28, 2026. How we read filings

Reading these numbers

Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →