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

Rhea-AI Filing Summary

Eric Swayze, EVP Research at Ionis Pharmaceuticals (IONS), reported insider sales on 09/02/2025. He sold 10,000 shares at a weighted average price of $49.22 and 1,130 shares at a weighted average price of $53.6829 under a Rule 10b5-1 trading plan adopted August 14, 2024. After these transactions the filing shows beneficial ownership figures of 38,432 and 37,302 shares respectively, and an indirect holding of 184 shares held by his son. The Form 4 was signed by an attorney-in-fact on 09/04/2025.

Positive

• Sales executed under a Rule 10b5-1 trading plan, indicating pre-planned transactions and potential affirmative defense to insider trading claims
• Weighted average prices and price ranges disclosed, with an undertaking to provide detailed per-price breakdowns on request
• Timely filing and signature by attorney-in-fact recorded on 09/04/2025, supporting regulatory disclosure compliance

Negative

• Insider sold 11,130 shares in total (10,000 and 1,130), reducing reported direct beneficial ownership levels
• Form does not state percent ownership or prior holdings on this filing, limiting context on the materiality of the sales

Insights

Financial Analyst

TL;DR: Routine, pre-planned insider sales; limited immediate signal about company fundamentals.

The reported sales total 11,130 shares executed under a documented 10b5-1 plan, which typically indicates pre-scheduled transactions rather than opportunistic trades. The weighted average prices reported provide transparency about execution ranges. The remaining direct beneficial ownership levels reported on the form should be compared to prior filings to assess change in percent ownership, which is not provided here. No derivatives or other compensatory transactions are disclosed on this Form 4.

Corporate Governance Expert

TL;DR: Use of a 10b5-1 plan and timely Form 4 filing align with standard governance and disclosure practices.

The filing documents that the reporting person adopted a Rule 10b5-1 trading plan on August 14, 2024 and that sales occurred on September 2, 2025, consistent with an affirmative defense to insider trading claims. The disclosure includes weighted average price ranges and an undertaking to provide further breakdowns upon request, which supports transparency. The signature by attorney-in-fact is noted and the relationship to the issuer is clearly stated as EVP Research.

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^*

Swayze Eric

(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)

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

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		10,000(1)	D	$49.22(2)	38,432	D
Common Stock	09/02/2025		S		1,130(1)	D	$53.6829(3)	37,302	D
Common Stock								184	I	by Son

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 August 14, 2024.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $49.14 to $49.54 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 $53.64 to $53.72 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.

	By: Patrick R. O'Neil, attorney-in-fact For: Eric Swayze	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 did Eric Swayze (IONS) report on the Form 4?

He reported sales of 10,000 shares at a weighted average $49.22 and 1,130 shares at a weighted average $53.6829 on 09/02/2025.

Were the transactions part of a 10b5-1 plan for IONS insider Eric Swayze?

Yes. The sales were made pursuant to a Rule 10b5-1 trading plan adopted August 14, 2024.

How many shares does the filing show as beneficially owned after the reported trades?

The filing shows beneficial ownership figures of 38,432 and 37,302 shares following the reported transactions, plus 184 shares indirectly owned by his son.

When was the Form 4 filed and who signed it?

The form shows an attorney-in-fact, Patrick R. O'Neil, signed on behalf of Eric Swayze on 09/04/2025.

Does this Form 4 disclose any derivative transactions or options?

No derivative securities or option transactions are disclosed on this Form 4.