Ionis (IONS) EVP earns PRSU shares and sells 6,179 at $83

Rhea-AI Filing Summary

Ionis Pharmaceuticals executive Brian Birchler reported an equity award and a share sale. On 01/29/2026, he acquired 11,991 shares of common stock at $0.0 per share upon vesting of performance-based restricted stock units tied to relative total shareholder return, which vested at 167.27% of target.

On 01/30/2026, Birchler sold 6,179 common shares at a weighted average price of $83.0309, in multiple trades between $83.00 and $83.08. After these transactions, he directly owned 66,247 Ionis shares as EVP, Corp and Development Ops.

Insider Trade Summary

Net Seller: 6,179 shares ($513,048)

Net Sell 2 txns

Insider Birchler Brian

Role EVP, Corp and Development Ops

Sold 6,179 shs ($513K)

Type	Security	Shares	Price	Value
Sale	Common Stock	6,179	$83.0309	$513K
Grant/Award	Common Stock	11,991	$0.00	--

Holdings After Transaction: Common Stock — 66,247 shares (Direct)

Footnotes (1)

1. Represents shares earned upon the vesting of performance-based restricted stock units ("PRSUs") for the performance period of the grant to the reporting person reported on January 18, 2023. The Compensation Committee certified achievement of the pre-established performance goal based on the Issuer's relative total shareholder return as compared to a peer group of companies at a level resulting in a vest of 167.27% of target shares. As reported at grant, the PRSUs could result in a payout of 0% to 200% based on actual achievement of the goal. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $83.00 to $83.08 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.

Form 4 Insider Transactions: What Each Field Means →

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).

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^*

Birchler Brian

(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, Corp and Development Ops

3. Date of Earliest Transaction (Month/Day/Year)
01/29/2026

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	01/29/2026		A		11,991(1)	A	$0.0	72,426	D
Common Stock	01/30/2026		S		6,179	D	$83.0309(2)	66,247	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. Represents shares earned upon the vesting of performance-based restricted stock units ("PRSUs") for the performance period of the grant to the reporting person reported on January 18, 2023. The Compensation Committee certified achievement of the pre-established performance goal based on the Issuer's relative total shareholder return as compared to a peer group of companies at a level resulting in a vest of 167.27% of target shares. As reported at grant, the PRSUs could result in a payout of 0% to 200% based on actual achievement of the goal.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $83.00 to $83.08 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: Brian Birchler	02/02/2026
	** 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 transactions did Ionis (IONS) EVP Brian Birchler report?

Brian Birchler reported receiving 11,991 Ionis common shares from vested performance-based RSUs and selling 6,179 shares. The sale occurred at a weighted average price of $83.0309 per share, leaving him with 66,247 shares directly owned after the transactions.

How were the 11,991 Ionis (IONS) shares earned by the executive?

The 11,991 shares were earned upon vesting of performance-based RSUs granted in 2023. Vesting was based on Ionis’ relative total shareholder return versus a peer group, with performance certified at 167.27% of target, within a potential payout range of 0% to 200%.

At what price did the Ionis (IONS) EVP sell his shares?

He sold 6,179 Ionis common shares at a weighted average price of $83.0309 per share. The transactions occurred in multiple trades, with individual prices ranging from $83.00 to $83.08, as disclosed in the Form 4 footnote for this insider sale.

How many Ionis (IONS) shares does Brian Birchler own after these transactions?

Following the reported acquisition and sale, Brian Birchler directly owns 66,247 Ionis common shares. This figure reflects the addition of 11,991 performance-based RSU shares and the subsequent sale of 6,179 shares disclosed in the Form 4 filing.

What role does Brian Birchler hold at Ionis (IONS)?

Brian Birchler serves as Executive Vice President, Corporate and Development Operations at Ionis Pharmaceuticals. His position is disclosed in the Form 4, which reports his direct ownership changes in Ionis common stock through equity award vesting and subsequent share sales.

How was performance measured for the Ionis (IONS) PRSU award?

The PRSU award’s performance was based on Ionis’ relative total shareholder return versus a designated peer group. The Compensation Committee certified achievement at 167.27% of target shares, within a plan design that allowed payouts from 0% to 200% depending on goal attainment.