Edgar Filing: ARROWHEAD RESEARCH CORP

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 ^*

KNOTT DAVID M

2. Issuer Name and Ticker or Trading Symbol
ARROWHEAD RESEARCH CORP [ARWR]

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)

485 UNDERHILL BLVD, SUITE 205

3. Date of Earliest Transaction (Month/Day/Year)
08/16/2006

(Street)

SYOSSET, NY 11791

4. If Amendment, Date Original Filed(Month/Day/Year)

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 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)
1.Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock, $0.001 par value per share	08/16/2006		P		4,500	A	$ 4.88	44,800	I	By Finderne LLC (formerly, Anno, L.P.) ⁽¹⁾
Common Stock, $0.001 par value per share	08/16/2006		P		74,450	A	$ 4.88	1,813,631	I	By Matterhorn Offshore Fund Limited ⁽¹⁾
Common Stock, $0.001 par value per share	08/16/2006		P		19,000	A	$ 4.88	752,800	I	By Shoshone Partners, LP ⁽¹⁾
Common Stock, $0.001 par value per share	08/16/2006		P		4,300	A	$ 4.88	4,300	I	By Mulsanne Partners LP ⁽¹⁾

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
KNOTT DAVID M 485 UNDERHILL BLVD SUITE 205 SYOSSET, NY 11791		X

Signatures

David M. Knott		08/16/2006
^**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)	The Reporting Person is the managing member of Knott Partners Management, LLC, which is the general partner of Shoshone Partners, L.P. and Knott Partners, L.P. In addition, the Reporting Person is the sole shareholder, director and president of Dorset Management Corporation, which provides investment management services to those entities listed in Table I(7). As a result of the Reporting Person's interests in Knott Partners Management, LLC and Dorset Management Corporation, the Reporting Person has investment discretion and control in the securities in Table I(5). The Reporting Person may be deemed to beneficially own indirect pecuniary interest in securities in Table I(5) as a result of a performance related fee. The Reporting Person disclaims beneficial ownership therein except to the extent ultimately realized.

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