Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Zago Wagner M.
2. Date of Event Requiring Statement (Month/Day/Year)
06/09/2017
3. Issuer Name and Ticker or Trading Symbol
Prothena Corp plc [PRTA]
(Last)
(First)
(Middle)
C/O PROTHENA BIOSCIENCES INC, 331 OYSTER POINT BOULEVARD
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Scientific Officer
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SOUTH SAN FRANCISCO, CA 94080
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (right to buy)   (1) 01/29/2023 Common Stock 16,000 $ 6.41 D  
Stock Option (right to buy)   (2) 09/03/2023 Common Stock 15,000 $ 20.17 D  
Stock Option (right to buy)   (3) 02/04/2024 Common Stock 15,000 $ 29.81 D  
Stock Option (right to buy)   (4) 03/11/2025 Common Stock 19,000 $ 27.81 D  
Stock Option (right to buy)   (5) 02/24/2026 Common Stock 21,000 $ 34.61 D  
Stock Option (right to buy)   (6) 02/22/2027 Common Stock 20,000 $ 55 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Zago Wagner M.
C/O PROTHENA BIOSCIENCES INC
331 OYSTER POINT BOULEVARD
SOUTH SAN FRANCISCO, CA 94080
      Chief Scientific Officer  

Signatures

/s/ A.W. Homan, as Attorney-in-Fact for Wagner M. Zago 06/13/2017
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The original grant was for 36,000 shares, of which 20,000 shares have been exercised and sold. The remaining shares underlying the option (16, 000 shares) are fully vested and exercisable as of the date hereof.
(2) A portion of the shares (14,062 shares) underlying this option are vested and exercisable as of the date hereof. The remaining shares subject to the option (938 shares) vest in successive, equal monthly installments through September 3, 2017, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.
(3) A portion of the shares (12,500 shares) underlying this option are vested and exercisable as of the date hereof. The remaining shares subject to the option (2,500 shares) vest in successive, equal monthly installments through February 4, 2018, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.
(4) A portion of the shares (10,291 shares) underlying this option are vested and exercisable as of the date hereof. The remaining shares subject to the option (8,709 shares) vest in successive, equal monthly installments through March 11, 2019, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.
(5) A portion of the shares (6,562 shares) underlying this option are vested and exercisable as of the date hereof. The remaining shares subject to the option (14,438 shares) vest in successive, equal monthly installments through February 24, 2020, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.
(6) The shares subject to the option will vest and become exercisable as to 25% of the total number of shares subject to the option on February 22, 2018 and with respect to 1/48th of the total number of shares subject to the option in successive, equal monthly installments on each monthly anniversary thereafter, subject to the Reporting Person's continued employment with the Issuer on each such vesting date.

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