[Form 4] Ionis Pharmaceuticals, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Joseph H. Wender, a director of Ionis Pharmaceuticals, Inc. (IONS), reported sales of company common stock under a Rule 10b5-1 trading plan. On 09/02/2025 he sold 11,200 shares at a weighted average price of $55.0386 and 5,600 shares at a weighted average price of $57.5311, and on 09/03/2025 he sold 11,200 shares at a weighted average price of $60.1383. Following those transactions, the filing reports beneficial ownership levels of 125,635, 120,035 and 108,835 shares respectively, each listed as held indirectly by trust. The Form 4 states the trades were made pursuant to a 10b5-1 plan adopted December 16, 2024, and provides price ranges for the multiple executions behind each weighted average.

Positive

• Transactions executed under a documented Rule 10b5-1 plan, indicating pre-planned dispositions rather than opportunistic sales
• Weighted-average prices and execution ranges disclosed, and an undertaking to provide per-price execution details upon request
• Beneficial ownership amounts reported after each transaction, showing continued indirect holdings via trust

Negative

• Insider disposed of a total of 28,000 shares across 09/02/2025 and 09/03/2025, reducing beneficial ownership from earlier levels
• Reported holdings decreased to as low as 108,835 shares following the reported sales

Insights

Financial Analyst

TL;DR: Director executed systematic sales under a 10b5-1 plan, reducing indirect holdings while providing weighted-average pricing and execution transparency.

The filing discloses scheduled dispositions by an insider under a documented 10b5-1 plan, with sales across two dates and clear weighted-average prices and disclosed price ranges. This provides transparency about timing and price execution but results in a reduction in beneficial ownership as reported. For investors, the material facts are the number of shares sold, the weighted-average prices, and the remaining indirect holdings reported in the Form 4; no other operational or financial information is provided in this filing.

Corporate Governance Expert

TL;DR: The transactions follow a pre-established 10b5-1 plan, aligning with typical insider trading protocols and disclosure requirements.

The Form 4 explicitly states the trades were executed pursuant to a Rule 10b5-1 trading plan adopted December 16, 2024, and supplies weighted-average prices plus the ranges for multiple executions. The report also indicates the holdings are indirect via a trust. From a governance perspective, the filing meets disclosure standards by describing the plan basis and offering to provide detailed execution-level pricing on request. The filing does not include any amendments or additional governance actions.

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
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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^*

WENDER JOSEPH H

(Last) (First) (Middle)

2855 GAZELLE COURT

(Street)

CARLSBAD CA 92010

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
IONIS PHARMACEUTICALS INC [ IONS ]

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

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

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		11,200(1)	D	$55.0386(2)	125,635	I	by Trust
Common Stock	09/02/2025		S		5,600(1)	D	$57.5311(3)	120,035	I	by Trust
Common Stock	09/03/2025		S		11,200(1)	D	$60.1383(4)	108,835	I	by Trust

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 sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on December 16, 2024.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $55.000 to $55.180 inclusive. The reporting person undertakes to provide to Ionis Pharmaceuticals, Inc. any security holder of Ionis Pharmaceuticals, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) on this Form 4.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $57.500 to $57.575 inclusive. The reporting person undertakes to provide to Ionis Pharmaceuticals, Inc. any security holder of Ionis Pharmaceuticals, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (3) on this Form 4.

4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $60.00 to $60.53 inclusive. The reporting person undertakes to provide to Ionis Pharmaceuticals, Inc. any security holder of Ionis Pharmaceuticals, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (4) on this Form 4.

	By: Patrick R. O'Neil, attorney-in-fact For: Joseph H. Wender	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 insider activity did Ionis Pharmaceuticals (IONS) disclose in this Form 4?

The filing reports that director Joseph H. Wender sold shares under a Rule 10b5-1 plan: 11,200 shares on 09/02/2025 at a weighted average $55.0386, 5,600 shares on 09/02/2025 at $57.5311, and 11,200 shares on 09/03/2025 at $60.1383.

Were the sales part of a pre-existing trading plan for IONS insider transactions?

Yes. The Form 4 states the shares were sold pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 16, 2024.

How many shares did Joseph H. Wender beneficially own after these transactions?

The Form 4 lists beneficial ownership amounts after the transactions as 125,635, 120,035, and 108,835 shares, each reported as indirectly held by a trust.

Does the filing provide exact execution prices for each share sale?

The filing provides weighted-average prices and price ranges for the multiple transactions and offers to provide the exact per-price execution details to Ionis, security holders, or the SEC upon request.

Who signed the Form 4 for the reporting person?

The Form 4 was executed by Patrick R. O'Neil, attorney-in-fact for Joseph H. Wender on 09/04/2025.