STOCK TITAN

Ionis (NASDAQ: IONS) director exercises 10,111 options and sells shares under 10b5-1 plan

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

Ionis Pharmaceuticals director Joseph Klein III exercised a non-qualified stock option for 10,111 shares of common stock at an exercise price of $47.11 per share and, on the same date, sold 10,111 shares in open-market transactions under a pre-arranged Rule 10b5-1 Trading Plan. The sales consisted of 8,680 shares at a weighted-average price of $73.3530 and 1,431 shares at a weighted-average price of $74.4474. Following these transactions, Klein held 11,014 shares of Ionis common stock directly. An additional 100 shares are held indirectly by his son, and Klein disclaims beneficial ownership of those shares.

Positive

  • None.

Negative

  • None.
Insider KLEIN JOSEPH III
Role null
Sold 10,111 shs ($743K)
Type Security Shares Price Value
Exercise Non-Qualified Stock Option (right to buy) 10,111 $0.00 --
Exercise Common Stock 10,111 $47.11 $476K
Sale Common Stock 8,680 $73.353 $637K
Sale Common Stock 1,431 $74.4474 $107K
holding Common Stock -- -- --
Holdings After Transaction: Non-Qualified Stock Option (right to buy) — 0 shares (Direct, null); Common Stock — 21,125 shares (Direct, null); Common Stock — 100 shares (Indirect, by Son)
Footnotes (1)
  1. Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on November 25, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $72.95 to $73.64 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. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $74.07 to $74.92 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. The reporting person disclaims beneficial ownership of all securities held by his son, and this report should not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.
Options exercised 10,111 shares Non-qualified stock option for common stock exercised at $47.11
Exercise price $47.11 per share Exercise price of non-qualified stock option for 10,111 shares
Shares sold (block 1) 8,680 shares at $73.3530 Open-market sale of common stock on 2026-05-01
Shares sold (block 2) 1,431 shares at $74.4474 Open-market sale of common stock on 2026-05-01
Net shares sold 10,111 shares Net sell shares from transactionSummary
Direct holdings after 11,014 shares Total Ionis common stock held directly after transactions
Indirect holdings by son 100 shares Shares held by son; beneficial ownership disclaimed by Klein
Rule 10b5-1 Trading Plan financial
"Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person"
A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.
Non-Qualified Stock Option financial
"Non-Qualified Stock Option (right to buy) with 10,111 underlying shares"
A non-qualified stock option (NSO) is a contract that lets an employee or service provider buy company shares at a fixed price for a set period, like a voucher to purchase stock later at today’s price. It matters to investors because exercising NSOs creates ordinary income for the holder and can increase share count, affecting a company’s earnings and ownership mix; think of it as a future sale that can dilute existing shareholders and has immediate tax consequences for the recipient.
weighted average price financial
"The price reported in Column 4 is a weighted average price"
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
beneficial ownership financial
"The reporting person disclaims beneficial ownership of all securities held by his son"
Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.
Section 16 regulatory
"not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16"
Section 16 is a U.S. securities law rule that governs the trading and disclosure obligations of company insiders — typically officers, directors and large shareholders — to promote transparency and deter unfair profit-taking. It requires insiders to publicly report their stock trades and allows companies or the issuer to reclaim quick, short-term profits from certain insider trades, like a scoreboard and a refund policy that help investors see and limit possible insider advantage.
SEC Form 4
FORM 4UNITED 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*
KLEIN JOSEPH III

(Last)(First)(Middle)
2855 GAZELLE COURT

(Street)
CARLSBAD CALIFORNIA 92010

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
IONIS PHARMACEUTICALS INC [ IONS ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/01/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

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)
CodeVAmount(A) or (D)Price
Common Stock05/01/2026M10,111A$47.1121,125D
Common Stock05/01/2026S8,680(1)D$73.353(2)12,445D
Common Stock05/01/2026S1,431(1)D$74.4474(3)11,014D
Common Stock100Iby Son(4)
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)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Non-Qualified Stock Option (right to buy)$47.1105/01/2026M10,11107/01/202506/30/2034Common Stock10,111$0.00D
Explanation of Responses:
1. Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on November 25, 2025.
2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $72.95 to $73.64 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 $74.07 to $74.92 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.
4. The reporting person disclaims beneficial ownership of all securities held by his son, and this report should not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.
By: Patrick R. O'Neil, attorney-in-fact For: Joseph Klein, III05/04/2026
** Signature of Reporting PersonDate
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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions did Ionis (IONS) director Joseph Klein report on this Form 4?

Joseph Klein reported exercising options for 10,111 Ionis shares and selling 10,111 shares of common stock in open-market transactions. The activity reflects an exercise-and-sell pattern, leaving his overall direct share ownership at 11,014 Ionis shares after the reported transactions.

At what prices did Joseph Klein’s Ionis (IONS) share sales occur on this Form 4?

Klein sold 8,680 Ionis shares at a weighted-average price of $73.3530 and 1,431 shares at a weighted-average price of $74.4474. Each weighted-average covers multiple trades within disclosed price ranges, as detailed in the Form 4 footnotes for the reported transactions.

How many Ionis (IONS) shares does Joseph Klein hold after the reported Form 4 transactions?

After the reported exercise and sales, Joseph Klein directly owns 11,014 shares of Ionis common stock. The filing also notes 100 shares held indirectly by his son, for which Klein expressly disclaims beneficial ownership under Section 16 of the securities laws.

Were Joseph Klein’s Ionis (IONS) stock sales part of a Rule 10b5-1 trading plan?

Yes, the Form 4 states that the shares were sold pursuant to a Rule 10b5-1 Trading Plan adopted by Joseph Klein. Such plans pre-schedule trades, indicating the timing of these sales was arranged in advance rather than based on real-time market information or personal discretion.

What stock option activity did Joseph Klein report for Ionis (IONS) on this Form 4?

Klein exercised a non-qualified stock option covering 10,111 Ionis common shares at an exercise price of $47.11 per share. After this exercise, the option position reported in the filing shows zero remaining derivative shares, meaning that particular option grant was fully exercised.

Does Joseph Klein claim beneficial ownership of Ionis (IONS) shares held by his son?

No. The Form 4 explicitly states that Klein disclaims beneficial ownership of all securities held by his son. The 100 shares recorded as held "by Son" are therefore not treated as beneficially owned by Klein for Section 16 or any other legal purpose.