[Form 4] Arrowhead Research Corporation Insider Trading Activity

Rhea-AI Filing Summary

Insider sale under 10b5-1 plan: James C. Hamilton, Chief Medical Officer of Arrowhead Pharmaceuticals (ARWR), reported a sale of 15,000 shares of common stock executed pursuant to a Rule 10b5-1 trading plan at a price of $25 per share, reducing his reported beneficial ownership to 247,122 shares. The filing notes that the remaining reported shares include previously disclosed restricted stock units, some of which remain subject to vesting conditions. No options, warrants, or other derivative transactions are reported.

Positive

• Transaction executed under a 10b5-1 plan, indicating prearranged, compliant insider trading procedures.
• Disclosure includes RSU treatment, clarifying that part of the reported holdings are subject to vesting conditions.

Negative

• Insider sale reduced direct holdings by 15,000 shares to 247,122 reported shares.
• No information on remaining lock-up or vesting schedules for the restricted stock units beyond the statement they are partially unvested.

Insights

Financial Analyst

TL;DR: A routine, prearranged insider sale that modestly reduces executive shareholdings; no derivatives or additional compensation changes reported.

This transaction appears to be a planned disposition under a 10b5-1 policy, which typically signals routine liquidity rather than a reactive sale. The sale size (15,000 shares) is small relative to the post-transaction holdings reported (247,122 shares), so the economic stake remains material but reduced. Absence of derivative activity keeps capital structure unchanged. For investors, this is a disclosure of insider liquidity rather than a corporate governance or operational signal.

Corporate Governance Expert

TL;DR: Governance-compliant execution under a 10b5-1 plan; disclosure includes vested and unvested equity components.

The reporting explicitly cites a 10b5-1 trading plan, indicating the sale was pre-authorized and intended to provide the affirmative defense to insider trading allegations. The filing also clarifies that reported shares include restricted stock units with vesting conditions, which is important for assessing true economic ownership and voting power. This disclosure meets Section 16 reporting expectations and supports transparency around executive equity movements.

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Hamilton James C

(Last) (First) (Middle)

177 EAST COLORADO BLVD

SUITE 700

(Street)

PASADENA CA 91105

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ARROWHEAD PHARMACEUTICALS, INC. [ ARWR ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Medical Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/02/2025

4. If Amendment, Date of 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

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	09/02/2025		S(1)		15,000	D	$25	247,122(2)	D

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 Securities Underlying Derivative Security (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: 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

Explanation of Responses:

1. Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

2. Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person, a portion of which are still subject to certain vesting conditions.

Remarks:

	/s/James Hamilton	09/04/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transaction did ARWR insider James C. Hamilton report?

He reported a sale of 15,000 shares of Arrowhead Pharmaceuticals common stock executed under a 10b5-1 trading plan at $25 per share.

What is James C. Hamilton's role at ARWR and how many shares does he own after the sale?

He is the Chief Medical Officer and reported beneficial ownership of 247,122 shares following the reported transaction.

Were any derivative securities reported in this Form 4?

No. The filing reports only a non-derivative sale of common stock and shows no derivative securities acquired or disposed of.

Why was the sale made under a 10b5-1 plan?

The filing states the shares were sold pursuant to a 10b5-1 trading plan, which provides an affirmative defense to insider trading claims when transactions are prearranged.

Does the filing disclose whether reported shares include unvested awards?

Yes. The filing notes the post-transaction total includes previously reported restricted stock units, a portion of which remain subject to vesting conditions.