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

Rhea-AI Filing Summary

Insider transactions by Joseph T. Baroldi at Ionis Pharmaceuticals (IONS) On 09/09/2025 Mr. Baroldi executed related transactions reported on Form 4. He exercised a non-qualified stock option with a $31.80 exercise price to acquire 11,950 shares and, pursuant to a Rule 10b5-1 trading plan adopted May 2, 2025, sold 11,950 shares at a weighted-average price of $62.1622 (individual sale prices ranged $62.00–$62.44). The Form 4 shows beneficial ownership figures of 43,876 shares (after the acquisition line) and 31,926 shares (after the sale line), and additionally notes 3,071 shares indirectly owned by his spouse. The filing was signed by an attorney-in-fact on 09/10/2025.

Positive

• Exercise and sale fully disclosed: Form 4 lists option exercise price ($31.80), shares exercised (11,950), and shares sold (11,950).
• Rule 10b5-1 plan disclosed: Sales were made under a 10b5-1 trading plan adopted May 2, 2025, providing affirmative-defense context.
• Sale pricing transparency: Weighted-average sale price reported ($62.1622) and range provided ($62.00–$62.44).

Negative

• None.

Insights

Securities Analyst

TL;DR Insider exercised options and immediately sold an equal number of shares under a pre-existing 10b5-1 plan; transactions are routine disclosure.

The report documents a typical exercise-and-sell sequence: a non-qualified option exercised at $31.80 for 11,950 shares and contemporaneous sales of 11,950 shares under a 10b5-1 plan at a weighted-average of $62.1622. The filing explicitly discloses the 10b5-1 plan adoption date (May 2, 2025) and the price range for sales. These are transparent, rule-compliant transactions and materially routine for insider liquidity events.

Corporate Governance Expert

TL;DR Disclosure is complete for the transactions shown: exercise, sales under a trading plan, weighted-average sale price and plan adoption date are provided.

The Form 4 includes required elements: transaction codes, share counts, exercise price, weighted-average sale price with stated price range, and an explicit statement that sales were pursuant to a Rule 10b5-1 trading plan. Beneficial ownership lines list direct and indirect holdings, and the filer provides to the company and SEC the ability to supply per-price breakouts on request. From a governance perspective, the filing meets standard disclosure expectations.

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^*

Baroldi Joseph

(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, Chief Business Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/09/2025

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	09/09/2025		M		11,950	A	$31.8	43,876	D
Common Stock	09/09/2025		S		11,950(1)	D	$62.1622(2)	31,926	D
Common Stock								3,071	I	by Spouse

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
Non-Qualified Stock Option (right to buy)	$31.8	09/09/2025		M			11,950	01/31/2023	01/30/2032	Common Stock	11,950	$0.0	41,700	D

Explanation of Responses:

1. Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on May 2, 2025.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $62.00 to $62.44 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: Joseph T. Baroldi	09/10/2025
	** 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 transactions did Joseph T. Baroldi report for IONS on 09/09/2025?

He exercised a non-qualified stock option for 11,950 shares at $31.80 and sold 11,950 shares pursuant to a Rule 10b5-1 plan.

At what price were the IONS shares sold according to the Form 4?

The Form 4 reports a weighted-average sale price of $62.1622, with individual sale prices ranging from $62.00 to $62.44.

When was the 10b5-1 trading plan adopted for the reported sales?

The reporting person adopted the Rule 10b5-1 trading plan on May 2, 2025, as stated in the filing.

How many IONS shares does the Form 4 show as beneficially owned after the transactions?

The filing shows 43,876 shares on the acquisition line and 31,926 shares on the sale line; it also reports 3,071 shares indirectly owned by the reporting person's spouse.

Who signed the Form 4 filing for Joseph T. Baroldi?

The Form 4 was signed by Patrick R. O'Neil, attorney-in-fact for Joseph T. Baroldi on 09/10/2025.