Company · Ownership research

PROTHENA CORP PUBLIC LTD CO PRTA

CIK 0001559053 · CUSIP G72800108

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP G72800108 (PRTA), not CUSIP G72800908 (PRTA), CUSIP G72800958 (PRTA), and does not merge CUSIPs.

This page lists the top 20 of 185 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	FMR LLC CIK 315066 · View history	$73.40M 7,551,218 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
02	Rubric Capital Management LP CIK 1687509 · View history	$48.60M 5,000,000 shares	0.60%	+1.32M(+36.00%)Added	SEC filing ↗ May 15, 2026	▾
03	BlackRock, Inc. CIK 2012383 · View history	$45.14M 4,644,160 shares	0.00%	+536.70K(+13.10%)Added	SEC filing ↗ May 13, 2026	▾
04	STATE STREET CORP CIK 93751 · View history	$18.84M 1,938,498 shares	0.00%	-329.30K(-14.50%)Reduced	SEC filing ↗ May 15, 2026	▾
05	D. E. Shaw & Co., Inc. CIK 1009207 · View history	$17.14M 1,763,347 shares	0.01%	+81.98K(+4.90%)Added	SEC filing ↗ May 15, 2026	▾
06	ADAR1 Capital Management, LLC CIK 1940272 · View history	$15.37M 1,581,443 shares	0.92%	+123.68K(+8.50%)Added	SEC filing ↗ May 18, 2026	▾
07	ACADIAN ASSET MANAGEMENT LLC CIK 916542 · View history	$15.04M 1,547,593 shares	0.02%	+110.23K(+7.70%)Added	SEC filing ↗ May 13, 2026	▾
08	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$14.05M 1,445,979 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
09	MORGAN STANLEY CIK 895421 · View history	$11.96M 1,230,448 shares	0.00%	-16.33K(-1.30%)Reduced	SEC filing ↗ May 15, 2026	▾
10	Palo Alto Investors LP CIK 1306923 · View history	$11.75M 1,208,568 shares	1.80%	-111.94K(-8.50%)Reduced	SEC filing ↗ May 15, 2026	▾
11	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$11.72M 1,205,978 shares	0.01%	+535.84K(+80.00%)Added	SEC filing ↗ May 15, 2026	▾
12	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$10.68M 1,098,166 shares	0.00%	+35.10K(+3.30%)Added	SEC filing ↗ May 15, 2026	▾
13	FEDERATED HERMES, INC. CIK 1056288 · View history	$10.30M 1,059,849 shares	0.02%	+85.48K(+8.80%)Added	SEC filing ↗ May 11, 2026	▾
14	JACOBS LEVY EQUITY MANAGEMENT, INC CIK 884414 · View history	$9.45M 972,017 shares	0.04%	-5.99K(-0.60%)Reduced	SEC filing ↗ May 15, 2026	▾
15	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$7.96M 818,885 shares	0.00%	-116.45K(-12.40%)Reduced	SEC filing ↗ May 15, 2026	▾
16	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$7.61M 782,603 shares	0.00%	+7.40K(+1.00%)Added	SEC filing ↗ May 7, 2026	▾
17	Nuveen, LLC CIK 1871926 · View history	$7.38M 759,368 shares	0.00%	+261(0.00%)Added	SEC filing ↗ Apr 30, 2026	▾
18	Qube Research & Technologies Ltd CIK 1729829 · View history	$5.97M 614,603 shares	0.01%	+206.91K(+50.80%)Added	SEC filing ↗ May 15, 2026	▾
19	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$5.91M 607,515 shares	0.01%	+172.00K(+39.50%)Added	SEC filing ↗ May 14, 2026	▾
20	Mariner, LLC CIK 1373442 · View history	$5.47M 563,082 shares	0.01%	-14.86K(-2.60%)Reduced	SEC filing ↗ May 13, 2026	▾

Showing 20 / 185 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

185

Cancelled or null records excluded

Disclosed shares

46,980,986

Not deduplicated across managers

Disclosed value

$456.62M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

PROTHENA CORP PUBLIC LTD CO · Q1 2026

Explore all 185 reporting institutions.

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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.