SCHEDULE 13G

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G
Under the Securities Exchange Act of 1934



PROTHENA CORPORATION PLC
(Name of Issuer)

ORDINARY SHARES, PAR VALUE $0.01 PER SHARE
(Title of Class of Securities)

G72800108
(CUSIP Number)

FEBRUARY 26, 2014
(Date of event which requires filing of this statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

     o Rule 13d-1(b)

     þ Rule 13d-1(c)

     o Rule 13d-1(d)

The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the notes).



                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
2
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Integrated Core Strategies (US) LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 716,000
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 716,000
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 716,000
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 3.27%
12 TYPE OF REPORTING PERSON

 OO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
3
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Integrated Assets II LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 7,029
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 7,029
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 7,029
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 0.03%
12 TYPE OF REPORTING PERSON

 
OO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
4
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Integrated Assets, Ltd.
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Cayman Islands
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 17,476
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 17,476
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 17,476
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 0.08%
12 TYPE OF REPORTING PERSON

 
CO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
5
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 ICS Opportunities, Ltd.
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Cayman Islands
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 341,033
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 341,033
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 341,033
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 1.56%
12 TYPE OF REPORTING PERSON

 
CO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
6
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Millennium International Management LP
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 358,509
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 358,509
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 358,509
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 1.64%
12 TYPE OF REPORTING PERSON

 
PN


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
7
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Millennium International Management GP LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 358,509
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 358,509
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 358,509
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 1.64%
12 TYPE OF REPORTING PERSON

 
OO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
8
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Millennium Management LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,081,538
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,081,538
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,081,538
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 4.94%
12 TYPE OF REPORTING PERSON

 
OO


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
9
  of   
16

1
 NAMES OF REPORTING PERSONS
 
 Israel A. Englander
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 United States
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,081,538
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,081,538
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,081,538
10
 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 4.94%
12
 TYPE OF REPORTING PERSON

 IN

                     
CUSIP No.
 
G72800108

 SCHEDULE 13G

Page  
10
  of   
16
 
Item 1.    
 
(a) Name of Issuer:
 
   
 
  Prothena Corporation plc, a public limited company formed under the the laws of Ireland (the "Issuer").
 
   
 
(b) Address of Issuer’s Principal Executive Offices:
 
   
 
 

650 Gateway Boulevard
South San Francisco, California 94080

     
Item 2.
(a) Name of Person Filing:
 
(b) Address of Principal Business Office:
 
(c) Citizenship:
     
 
  Integrated Core Strategies (US) LLC
c/o Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Integrated Assets II LLC
c/o Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Integrated Assets, Ltd.
c/o Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Cayman Islands
 
   
 
  ICS Opportunities, Ltd.
c/o Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Cayman Islands
 
   
 
  Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Millennium International Management GP LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Israel A. Englander
c/o Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: United States
 
   
  (d) Title of Class of Securities:
ordinary shares, par value $0.01 per share ("Ordinary Shares")
 
  (e) CUSIP Number:
     
    G72800108


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
11
  of   
16

Item 3.  If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b), check whether the person filing is a:

 
  (a)   o   Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
             
 
  (b)   o   Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
             
 
  (c)   o   Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
             
 
  (d)   o   Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
             
 
  (e)   o   An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
             
 
  (f)   o    An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

                     
CUSIP No.
 
G72800108

 SCHEDULE 13G

Page  
12
  of   
16
             
 
  (g)   o   A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
             
 
  (h)   o   A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
             
 
  (i)   o   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);
             
 
  (j)   o   Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Item 4. Ownership

   Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a) Amount Beneficially Owned

   As of the close of business on February 26, 2014: i) Integrated Core Strategies (US) LLC, a Delaware limited liability company ("Integrated Core Strategies"), beneficially owned 728,500 Ordinary Shares (consisting of 578,500 Ordinary Shares and listed options to acquire 150,000 Ordinary Shares); ii) Integrated Assets II LLC, a Delaware limited liability company ("Integrated Assets II"), beneficially owned 7,029 Ordinary Shares; iii) Integrated Assets, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("Integrated Assets"), beneficially owned 16,776 Ordinary Shares; and iv) ICS Opportunities, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("ICS Opportunities"), beneficially owned 345,216 Ordinary Shares (consisting of 306,916 Ordinary Shares and listed options to acquire 38,300 Ordinary Shares), which collectively represented 1,097,521 Ordinary Shares or 5.02% of the Issuer’s outstanding Ordinary Shares. The calculation of the foregoing percentage was based on 21,856,261 Ordinary Shares outstanding as of October 31, 2013, as per the Issuer’s Form 10-Q dated November 12, 2013.

   However, as of the close of business on March 6, 2014: i) Integrated Core Strategies beneficially owned 716,000 Ordinary Shares (consisting of 566,000 Ordinary Shares and listed options to acquire 150,000 Ordinary Shares); ii) Integrated Assets II beneficially owned 7,029 Ordinary Shares; iii) Integrated Assets beneficially owned 17,476 Ordinary Shares; and iv) ICS Opportunities beneficially owned 341,033 Ordinary Shares (consisting of 302,733 Ordinary Shares and listed options to acquire 38,300 Ordinary Shares), which collectively represented 1,081,538 Ordinary Shares or 4.94% of the Issuer’s outstanding Ordinary Shares. The calculation of the foregoing percentage was based on 21,902,937 Ordinary Shares outstanding as of March 3, 2014, as per the Issuer’s Form 10-K dated March 7, 2014.

   Millennium International Management LP, a Delaware limited partnership ("Millennium International Management"), is the investment manager to Integrated Assets and ICS Opportunities and may be deemed to have shared voting control and investment discretion over securities owned by Integrated Assets and ICS Opportunities.

   Millennium International Management GP LLC, a Delaware limited liability company ("Millennium International Management GP"), is the general partner of Millennium International Management and may also be deemed to have shared voting control and investment discretion over securities owned by Integrated Assets and ICS Opportunities.

   Millennium Management LLC, a Delaware limited liability company ("Millennium Management") is the general partner of the managing member of Integrated Core Strategies and Integrated Assets II and may be deemed to have shared voting control and investment discretion over securities owned by Integrated Core Strategies and Integrated Assets II. Millennium Management is also the general partner of the 100% shareholder of Integrated Assets and ICS Opportunities and may be deemed to have shared voting control and investment discretion over securities owned by Integrated Assets and ICS Opportunities.

   Israel A. Englander, a United States citizen ("Mr. Englander"), is the managing member of Millennium International Management GP and Millennium Management and may also be deemed to have shared voting control and investment discretion over securities owned by Integrated Core Strategies, Integrated Assets II, Integrated Assets and ICS Opportunities.

   The foregoing should not be construed in and of itself as an admission by Millennium International Management, Millennium International Management GP, Millennium Management or Mr. Englander as to beneficial ownership of the securities owned by Integrated Core Strategies, Integrated Assets II, Integrated Assets or ICS Opportunities, as the case may be.

(b) Percent of Class:   

   As of the close of business on March 6, 2014, Millennium Management and Mr. Englander may be deemed to have beneficially owned 1,081,538 shares or 4.94% of the Issuer’s Ordinary Shares outstanding (see Item 4(a) above), which percentage was calculated based on 21,902,937 Ordinary Shares outstanding as of March 3, 2014, as per the Issuer’s Form 10-K dated March 7, 2014.


                     
CUSIP No.
 
G72800108

 SCHEDULE 13G

Page  
13
  of   
16

 (c) Number of shares as to which such person has:

(i) Sole power to vote or to direct the vote

   -0-

(ii) Shared power to vote or to direct the vote

   1,081,538 (See Item 4(b))

 (iii) Sole power to dispose or to direct the disposition of

   -0-

(iv) Shared power to dispose or to direct the disposition of

   1,081,538 (See Item 4(b))

Item 5. Ownership of Five Percent or Less of a Class

   If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following þ .

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

    Not applicable.

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company.

    Not applicable.

Item 8. Identification and Classification of Members of the Group

    See Exhibit I.

Item 9. Notice of Dissolution of Group

    Not applicable.

Item 10. Certification 

   By signing below each of the undersigned certifies that, to the best of its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
14
  of   
16

Exhibits:

Exhibit I: Joint Filing Agreement, dated as of March 6, 2014, by and among Integrated Core Strategies (US) LLC, Integrated Assets II LLC, Integrated Assets, Ltd., ICS Opportunities, Ltd., Millennium International Management LP, Millennium International Management GP LLC, Millennium Management LLC and Israel A. Englander.


                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
15
  of   
16
                     
     

SIGNATURE

             

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information with respect to it set forth in this statement is true, complete, and correct.

Dated: March 6, 2014

INTEGRATED CORE STRATEGIES (US) LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS II LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

ICS OPPORTUNITIES, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT LP

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT GP LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM MANAGEMENT LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

/s/ Israel A. Englander by David Nolan
pursuant to Power of Attorney filed with
the SEC on June 6, 2005

Israel A. Englander



                     
CUSIP No.
 
G72800108

SCHEDULE 13G

Page  
16
  of   
16
                     
      EXHIBIT I              
                     
      JOINT FILING AGREEMENT              

This will confirm the agreement by and among the undersigned that the Schedule 13G filed with the Securities and Exchange Commission on or about the date hereof with respect to the beneficial ownership by the undersigned of the Ordinary Shares, par value $0.01 per share, of Prothena Corporation plc, a public limited company formed under the the laws of Ireland, will be filed on behalf of each of the persons and entities named below in accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

Dated: March 6, 2014

INTEGRATED CORE STRATEGIES (US) LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS II LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

ICS OPPORTUNITIES, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT LP

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT GP LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM MANAGEMENT LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

/s/ Israel A. Englander by David Nolan
pursuant to Power of Attorney filed with
the SEC on June 6, 2005

Israel A. Englander