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

Rhea-AI Filing Summary

Allene M. Diaz, a director of Ionis Pharmaceuticals (IONS), reported the sale of 1,427 shares of common stock on 08/22/2025 at a weighted-average price of $42.5278 per share, reducing her direct holdings to 18,368 shares. The sale was made pursuant to a Rule 10b5-1 trading plan adopted May 3, 2023, and the filing notes the shares were sold in multiple transactions at prices ranging $42.30 to $42.75. The Form 4 was signed by an attorney-in-fact on 08/26/2025.

Positive

• Sale executed under a pre-established Rule 10b5-1 trading plan
• Filing discloses weighted-average price and price range, offering transparency

Negative

• Director disposed of 1,427 shares, decreasing direct holdings to 18,368 shares

Insights

Securities Analyst

TL;DR: A director sold a small number of shares under a pre-established 10b5-1 plan; transaction appears routine and non-material to company capitalization.

The disposal of 1,427 shares at a weighted-average price of $42.5278 reduces Allene Diaz's direct stake to 18,368 shares. The transaction was executed under a documented Rule 10b5-1 plan, indicating it was pre-planned rather than opportunistic trading. For a company of Ionis Pharmaceuticals' size, this volume is modest and unlikely to affect market perceptions materially, though insiders selling can draw investor attention.

Corporate Governance Expert

TL;DR: Use of a 10b5-1 plan signals compliance with insider trading policies; disclosure is timely and includes price range detail.

The filer disclosed the transaction date, number of shares sold, weighted-average price, and that the sale occurred under a 10b5-1 plan adopted May 3, 2023. The explanatory footnote provides the price range and an offer to supply detailed per-trade pricing on request, which enhances transparency. This filing follows expected governance best practices for director trades.

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^*

Diaz Allene M.

(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)
08/22/2025

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	08/22/2025		S		1,427(1)	D	$42.5278(2)	18,368	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 sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on May 3, 2023

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.30 to $42.75 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.

	By: Patrick R. O'Neil, attorney-in-fact For For: Allene M. Diaz	08/26/2025
	** 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 Allene M. Diaz report on Form 4 for IONS?

She reported the sale of 1,427 shares of Ionis Pharmaceuticals common stock on 08/22/2025.

At what price were the IONS shares sold by the director?

The weighted-average sale price was $42.5278 per share, with individual trades ranging $42.30 to $42.75.

Was the sale by the IONS director part of a trading plan?

Yes. The shares were sold pursuant to a Rule 10b5-1 trading plan adopted May 3, 2023.

How many IONS shares does Allene M. Diaz own after the transaction?

She beneficially owns 18,368 shares following the reported sale.

Who signed the Form 4 for the reporting person?

The Form 4 was signed by attorney-in-fact Patrick R. O'Neil on behalf of Allene M. Diaz on 08/26/2025.