FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 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 *
Memorial Sloan-Kettering Cancer Center
   2. Issuer Name and Ticker or Trading Symbol
Actinium Pharmaceuticals, Inc. [ATNM] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
1275 YORK AVE., 		 3. Date of Earliest Transaction (Month/Day/Year)
05/06/2015
(Street)

NEW YORK, NY 10065		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 05/06/2015   J(1)   5,702,387 A (1) 5,702,387 D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Memorial Sloan-Kettering Cancer Center
1275 YORK AVE.
NEW YORK, NY 10065		     X    
AHLB Holdings, LLC
C/O MSKCC
1275 YORK AVE.
NEW YORK, NY 10065		     X    
Actinium Holdings, Ltd.
C/O /O STERLING MANAGEMENT, LTD.
P.O. BOX HM 29
HAMILTON HM CX, D0 00000		     X    

Signatures

 /s/ Memorial Sloan-Kettering Cancer Center, By Eric Cottington, PhD, its Sr. Vice President, Research & Technology Management   05/08/2015
**Signature of Reporting Person Date
 /s/ AHLB Holdings, LLC, By Memorial Sloan-Kettering Cancer Center, its sole member, By Eric Cottington, PhD, its Sr. Vice President, Research & Technology Management   05/08/2015
**Signature of Reporting Person Date
 /s/ Actinium Holdings Ltd., By Eric Cottington, PhD, its President   05/08/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) Represents a transfer of shares previously held directly by Actinium Holdings Ltd. ("AHL") to Memorial Sloan-Kettering Cancer Center ("MSKCC"). MSKCC owns all of the membership interests in AHLB Holdings, LLC ("AHLB"), which owns all of the outstanding shares of AHL. As a result of the transfer, AHL and AHLB are no longer deemed a beneficial owner of the shares. With respect to MSKCC, the transfer constitutes a change in the form of beneficial interest from indirect to direct in accordance with Rule 16a-13.

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