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 *
  Ching Marshall Robert
 2. Date of Event Requiring Statement (Month/Day/Year)
01/12/2004		 3. Issuer Name and Ticker or Trading Symbol
ARROWHEAD RESEARCH CORP [ARWR]
(Last)
(First)
(Middle)
1118 EAST GREEN STREET		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

PASADENA, CA 91106		 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)
common stock 295,507
D
 
common stock 1,125,000
D
 
common stock 311,248
I
held by Pension Plan (1)
common stock 71,066
I
held by Pension Plan (2)

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
common stock purchase warrant 01/12/2004 06/30/2013 common stock 1,125,000 $ 1.5 D  
common stock purchase warrant 01/31/2004 06/30/2013 common stock 704,487 $ 1.5 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Ching Marshall Robert
1118 EAST GREEN STREET
PASADENA, CA 91106		     X    

Signatures

M. Robert Ching 12/15/2004
**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) 311,248 shares of common stock are held by the M. Robert Ching Defined Benefit Pension Plan. Dr. Ching exercises beneficial ownership (voting and investment power) with respect to these shares.
(2) 71,066 shares of common stock are held by the M. Robert Ching Money Purchase Pension Plan. Dr. Ching exercises beneficial ownership (voting and investment power) with respect to these shares.

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