Company · Ownership research

PROTHENA CORP PUBLIC LTD CO PRTA

CIK 0001559053

Form 4 transactions dated Sep 1, 2023 to Sep 25, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

This page lists 30 of 37 rows; the complete set is available through the API.

Insider filings on file run through 2026-09-03.

Insider purchases & sales

Purchased: $6.87M
Sold: $53.23M

Sep 1, 2023 – Sep 3, 2026
Available records · partial months are marked ·

202610 of 11 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
2026-09-02	SCULLY WILLIAM P 10% owner	Purchase	$255.74K 27,000 shares bought	3.38% added Direct holding	▾
2026-08-20	SCULLY WILLIAM P 10% owner	Purchase	$439.43K 50,000 shares bought	6.67% added Direct holding	▾
2026-08-07	SCULLY WILLIAM P 10% owner	Purchase	$293.05K 34,000 shares bought	4.50% added Direct holding	▾
2026-08-07	SCULLY WILLIAM P 10% owner	Purchase	$30.17K 3,500 shares bought	4.38% added LLC holding	▾
2026-07-29	Kingston Anne Evans Chief Strategy Officer	Sale10b5-1 footnote	$64.92K 7,662 shares sold	12.08% sold Direct holding	▾
2026-07-29	Isaacs Michael John General Counsel & Company Sec.	Sale10b5-1 footnote	$71.06K 8,386 shares sold	19.00% sold Direct holding	▾
2026-06-16	SCULLY WILLIAM P 10% owner	Purchase	$157.99K 20,000 shares bought	2.72% added Direct holding	▾
2026-06-11	SCULLY WILLIAM P 10% owner	Purchase	$1.02M 125,000 shares bought	13.35% added Direct holding	▾
2026-06-04	SCULLY WILLIAM P 10% owner	Purchase	$465.30K 50,000 shares bought	5.64% added Direct holding	▾
2026-06-02	SCULLY WILLIAM P 10% owner	Purchase	$471.30K 50,000 shares bought	5.98% added Direct holding	▾

Showing 11 / 11 record groups in 2026. The complete set is available through the API.

PROTHENA CORP PUBLIC LTD CO · PRTA

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 11 of 11 purchase / sale groups and 30 of 37 other groups; the totals and the monthly series cover the whole window.

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{"ticker":"PRTA","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.