| Item 1. | |
| (a) | Name of issuer:
PROTHENA CORP PUBLIC LTD CO |
| (b) | Address of issuer's principal executive offices:
77 SIR JOHN ROGERSON'S QUAY, BLOCK C, 77 SIR JOHN ROGERSON'S QUAY, BLOCK C, DUBLIN 2, IRELAND, D02 VK60. |
| Item 2. | |
| (a) | Name of person filing:
William P. Scully |
| (b) | Address or principal business office or, if none, residence:
771 Manatee Cove, Vero Beach, Florida 32963 |
| (c) | Citizenship:
Florida |
| (d) | Title of class of securities:
Ordinary Shares, $0.01 par value |
| (e) | CUSIP No.:
G72800108 |
| Item 3. | If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a: |
| (a) |  Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
|
| (b) | Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
|
| (c) | Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
|
| (d) | Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
|
| (e) | An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
|
| (f) | An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
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| (g) | A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
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| (h) | A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
|
| (i) | A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
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| (j) | A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
|
| (k) | Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
|
| | |
| Item 4. | Ownership |
| (a) | Amount beneficially owned:
The Reporting Person may be deemed to be the beneficial owner of 5,281,846 Ordinary Shares. This amount consists of (i) 80,000 Ordinary Shares owned by Manatee Equity Fund LLC, of which the Reporting Person is the sole manager with sole voting and dispositive power, (ii) 683,000 Ordinary Shares owned by the Reporting Persons IRA, over which he has sole voting and dispositive power, (iii) 42,000 Ordinary Shares owned by the Reporting Persons spouses IRA, over which he may be deemed to have shared voting and dispositive power, (iv) 10,000 Ordinary Shares owned by the Reporting Persons spouse, over which he may be deemed to have shared voting and dispositive power (v) 23,000 Ordinary Shares owned by an IRA subject to an investment management agreement over which the Reporting Person may be deemed to have shared voting and dispositive power by reason of his right to terminate such agreement, (vii) 68,000 Ordinary Shares owned by a trust, of which the Reporting Person may be deemed to have shared voting and dispositive power by virtue of being a co-trustee, (viii) 4,335,846 Ordinary Shares owned in the aggregate by various grantor retained annuity trusts, which have an independent trustee, but over which the Reporting Person may be deemed to have shared voting and dispositive power by reason of his retained right to substitute assets in such trusts, and (ix) 40,000 Ordinary Shares owned by another trust, which has an independent trustee, but over which the Reporting Person may be deemed to have shared voting and dispositive power by reason of his retained right to substitute assets in such trust. |
| (b) | Percent of class:
According to the Issuers most recent Quarterly Report on Form 10-Q for the quarter ended September 30, 2025, the number of shares outstanding as of October 31, 2025 was 53,829,982. The Ordinary Shares which the Reporting Person may be deemed to beneficially own constitute approximately 9.81% of such total number of shares |
| (c) | Number of shares as to which the person has:
|
| | (i) Sole power to vote or to direct the vote:
763,000
|
| | (ii) Shared power to vote or to direct the vote:
4,518,846
|
| | (iii) Sole power to dispose or to direct the disposition of:
763,000
|
| | (iv) Shared power to dispose or to direct the disposition of:
4,518,846
|
| Item 5. | Ownership of 5 Percent or Less of a Class. |
| |
Not Applicable
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| Item 6. | Ownership of more than 5 Percent on Behalf of Another Person. |
| |
Not Applicable
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| Item 7. | Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person. |
| |
Not Applicable
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| Item 8. | Identification and Classification of Members of the Group. |
| |
Not Applicable
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| Item 9. | Notice of Dissolution of Group. |
| |
Not Applicable
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Rule 13d-1(c)