William P. Scully Insider Trades

10% owner

10% owner at Prothena Corp Public LTD Co. 9 significant open-market trades reported on SEC Form 4 in the last 180 days.

On EDGAR, this filer has 31 Form 4 filings on record since 2014, the latest on Oct 29, 2026. Full history on sec.gov

$8.1M

Bought

Sold

9 / 0

Buys / Sells

Companies

PRTA10% owner
Prothena Corp Public LTD Co
9 buys, $8.1M · 5 alerts in our log

Reported Trades

Open-market transactions only (code P and S), outside any 10b5-1 plan, dated by the day the filing reached EDGAR. Each row links to the filing.

Filed	Company	Trade	Value	Shares	Source
Oct 26, 2026	PRTA10% owner	buy	$1.2M	150,000	Form 4
Oct 15, 2026	PRTA10% owner	buy	$920K	110,000	Form 4
Oct 9, 2026	PRTA10% owner	buy	$1.8M	215,000	Form 4
Oct 6, 2026	PRTA10% owner	buy	$857K	100,000	Form 4
Sep 30, 2026	PRTA10% owner	buy	$1.4M	162,000	Form 4
Sep 29, 2026	PRTA10% owner	buy	$890K	103,500	Form 4
Sep 3, 2026	PRTA10% owner	buy	$256K	27,000	Form 4
Aug 21, 2026	PRTA10% owner	buy	$439K	50,000	Form 4
Aug 10, 2026	PRTA10% owner	buy	$323K	37,500	Form 4

How to Read This Page

These are the trades an insider chose to make with their own money, not grants, option exercises or tax withholding. A purchase is the stronger signal (why buys carry more information than sales), and an insider who buys is locked out of selling for six months by the short-swing rule. The window here is 180 days; the full filing history lives on EDGAR.

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