Prothena Corp Public Ltd Co (PRTA) ten-percent owner William P. Scully reported that Manatee Equity Fund LLC purchased 103,500 ordinary shares on September 28, 2026, at a weighted average of $8.5978 per share. The purchases occurred in multiple transactions at prices from $8.1582 to $8.8500, inclusive, and the fund held 187,000 shares afterward. Scully disclaimed beneficial ownership of the fund’s shares except to the extent of his pecuniary interest. Separately, the report lists 927,000 shares held directly and 52,000 held by his spouse.
For PROTHENA CORP PUBLIC LTD CO (PRTA), ten percent owner William P. Scully purchased 100,000 ordinary shares on September 18, 2026 at a weighted average price of $8.4346 per share, with individual purchase prices ranging from $8.3350 to $8.4829. After this open-market purchase, he directly holds 927,000 shares, and also reports indirect holdings of 83,500 shares by Manatee Equity Fund LLC and 52,000 shares held by his spouse, with beneficial ownership of the Manatee Equity Fund LLC position disclaimed except to the extent of his pecuniary interest. No Rule 10b5-1 trading plan is reported for these transactions.
PROTHENA CORP PUBLIC LTD CO (PRTA) reporting person William P. Scully, a ten percent owner, purchased 27,000 ordinary shares on September 2, 2026 in open-market or private transactions at a weighted average price of $9.4718 per share, with individual prices ranging from $9.4072 to $9.6100.
After this purchase, he holds 827,000 shares directly, plus indirect holdings of 83,500 shares through Manatee Equity Fund LLC (for which he disclaims beneficial ownership except to the extent of his pecuniary interest) and 52,000 shares held by his spouse. No Rule 10b5-1 trading plan is reported.
PROTHENA CORP PUBLIC LTD CO (PRTA) reported that ten percent owner William P. Scully purchased 50,000 Ordinary Shares on August 20, 2026, in an open-market or private transaction at a weighted average price of $8.7886 per share. The price reflects multiple purchases at prices ranging from $8.7497 to $8.9000. Following this transaction, Scully directly holds 800,000 Ordinary Shares. He also is reported as having indirect ownership of 83,500 shares held by Manatee Equity Fund LLC, for which he disclaims beneficial ownership except to the extent of his pecuniary interest, and 52,000 shares held by his spouse.
Prothena Corp Public Ltd Co (PRTA) reports in this amended Schedule 13G that Todd W. Fennell may be deemed the beneficial owner of 5,248,846 Ordinary Shares, held entirely through trusts where he serves as independent trustee. This represents approximately 10.22% of the Ordinary Shares outstanding, based on 51,336,974 shares outstanding as of July 30, 2026. All voting and dispositive authority over these shares is reported as shared, with no sole voting or dispositive power. Fennell disclaims beneficial ownership of shares in which he has no pecuniary interest and expressly disclaims any status as part of a group with any other party.
PROTHENA CORP PUBLIC LTD CO (PRTA) reported that Todd W. Fennell filed an initial statement of beneficial ownership on Form 3 as a ten percent owner. The filing does not list any specific transactions or current holdings, and shows no reported purchases, sales, or derivative exercises.
PROTHENA CORP PUBLIC LTD CO (PRTA) reported insider activity by ten percent owner William P. Scully involving bona fide gifts of its ordinary shares. On August 18, 2026, he disposed of 627,553 ordinary shares as a bona fide gift at a reported price of $0.00 per share. On August 17, 2026, he was reported as acquiring 336,000 ordinary shares in a bona fide gift transaction. After these transactions, indirect holdings reported include 83,500 shares held by Manatee Equity Fund LLC, as to which he disclaims beneficial ownership except to the extent of his pecuniary interest, and 52,000 shares held by his spouse.
Todd W. Fennell reports beneficial ownership of 5,010,846 Ordinary Shares of Prothena Corp Public Ltd Co, held entirely through various trusts where he serves as independent trustee. These shares represent approximately 9.76% of Prothena’s Ordinary Shares outstanding, based on 51,336,974 shares outstanding as of July 30, 2026.
All 5,010,846 shares are subject to shared voting and shared dispositive power, with no sole voting or dispositive authority reported. The filing states that Fennell disclaims beneficial ownership of any Ordinary Shares in which he does not have a pecuniary interest and expressly disclaims any status as part of a group with any other party.
SCULLY WILLIAM P reported acquisition or exercise transactions in this Form 4 filing.
Prothena Corp Public Ltd Co reporting person William P. Scully, identified as a ten percent owner, reported receiving a bona fide gift of 251,553 Ordinary Shares of the company on 2026-08-10 at a stated price of $0.00 per share. Following this gift, he directly holds 1,041,553 Ordinary Shares. He also reports indirect holdings of 83,500 shares through Manatee Equity Fund LLC, for which he disclaims beneficial ownership beyond his pecuniary interest, and 52,000 shares held by his spouse.
PROTHENA CORP PUBLIC LTD CO filed an initial statement of beneficial ownership identifying Todd W. Fennell as a ten percent owner of the company. The filing does not report any specific transactions or detailed holdings and includes a reference to a Power of Attorney as an exhibit.