[Form 4] IONIS PHARMACEUTICALS INC Insider Trading Activity

Rhea-AI Filing Summary

Ionis Pharmaceuticals (IONS) reported insider transactions by EVP Research Eric Swayze on a Form 4. On 10/15/2025, 125 shares of common stock were acquired at $0.00 upon vesting of a Restricted Stock Unit award, held indirectly by his son. On 10/16/2025, 53 shares were sold at $73.6213 pursuant to an automatic sale to cover required tax withholding.

Following these transactions, 256 shares were indirectly held by his son and 30,453 shares were held directly. Derivative holdings included 497 Restricted Stock Units indirectly held.

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

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)
10/15/2025

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	10/15/2025		M(1)		125(1)	A	$0.0	309	I	by Son
Common Stock	10/16/2025		S(2)		53(2)	D	$73.6213	256	I	by Son
Common Stock								30,453	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
Restricted Stock Unit	$0.0(3)	10/15/2025		M			125	10/15/2025(4)	(4)	Common Stock	125	$0.0	497	I	by Son

Explanation of Responses:

1. Acquired pursuant to vesting and release of shares in accordance with a Restricted Stock Unit award.

2. The sale was made pursuant to an automatic sale to cover the required tax withholding obligations pursuant to the 2011 Equity Incentive Plan Restricted Stock Unit Agreement and Grant Notice.

3. Each Restricted Stock Unit represents a contingent right to receive one share of Ionis common stock, or its equivalent cash value.

4. Restricted Stock Units vest in four equal annual installments. Upon vesting, the restricted stock units will be paid out in whole shares of Ionis common stock or cash as may be determined by the Company.

	By: Patrick R. O'Neil, attorney-in-fact For: Eric Swayze	10/16/2025
	** 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 Ionis (IONS) disclose in this Form 4?

An EVP’s transactions: 125 shares acquired via RSU vesting on 10/15/2025 and 53 shares sold on 10/16/2025 to cover tax withholding.

What was the sale price reported for Ionis (IONS)?

The filing shows a sale of 53 shares at $73.6213.

How many shares were acquired through RSU vesting?

The report shows 125 shares acquired at $0.00 upon RSU vesting.

What are the post-transaction holdings reported?

The filing lists 256 shares indirectly held by son and 30,453 shares held directly by the reporting person.

How many RSUs remain after the transactions?

The report shows 497 Restricted Stock Units indirectly held by son.

Who is the reporting person and role at Ionis (IONS)?

The reporting person is Eric Swayze, EVP Research.

Why was the sale executed on 10/16/2025?

The filing states the sale was an automatic sale to cover required tax withholding under the 2011 Equity Incentive Plan RSU Agreement.