Ownership Submission
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, 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 *
KIRK RANDAL J
   2. Issuer Name and Ticker or Trading Symbol
ZIOPHARM ONCOLOGY INC [ZIOP] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O THIRD SECURITY, LLC, 1881 GROVE AVENUE		 3. Date of Earliest Transaction (Month/Day/Year)
01/12/2011
(Street)

RADFORD, VA 24141		 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 01/12/2011   A   25,000 (1) A $ 0 25,000 D  
Common Shares 01/12/2011   P   2,426,235 A $ 4.8 2,426,235 I By Intrexon Corporation (2)
Common Stock 01/12/2011   P   3,636,926 A (3) 6,063,161 I By Intrexon Corporation (2)

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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
Option to Purchase Common Stock $ 5.21 01/12/2011   A   25,000     (4) 01/12/2021 Common Stock 25,000 $ 0 25,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
KIRK RANDAL J
C/O THIRD SECURITY, LLC
1881 GROVE AVENUE
RADFORD, VA 24141		   X   X    
INTREXON CORP
C/O LEGAL DEPARTMENT
20358 SENECA MEADOWS PARKWAY
GERMANTOWN, MD 20876		     X    

Signatures

 /s/ Randal J. Kirk   01/14/2011
**Signature of Reporting Person Date
 /s/ Randal J. Kirk, CEO of Intrexon Corporation   01/14/2011
**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) All restrictions related to the grant of restricted stock will lapse on January 12, 2012.
(2) Randal J. Kirk, directly and through certain affiliates, has voting and dispositive power over a majority of the outstanding capital stock of Intrexon Corporation. Mr. Kirk may therefore be deemed to have voting and dispositive power over the shares of the issuer owned by Intrexon Corporation. Mr. Kirk disclaims beneficial ownership of such shares, except to the extent of any pecuniary interest therein.
(3) Shares were issued as partial consideration in connection with the execution of an Exclusive Channel Partner Agreement dated January 6, 2011 between the issuer and Intrexon Corporation.
(4) Option to purchase shares of common stock will vest over a three (3) year period as follows: 8,334 shares on January 12, 2012; 8,333 shares on January 12, 2013; and 8,333 shares on January 12, 2014.

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