Ionis (NASDAQ: IONS) director sells 5,000 shares under Rule 10b5-1 plan

Filing Impact

(Moderate)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

IONIS PHARMACEUTICALS INC director Lynne B. Parshall reported selling 5,000 shares of common stock in open-market transactions. The sales occurred on April 15, 2026 in two tranches: 4,466 shares at a weighted average price of $76.19 and 534 shares at a weighted average price of $76.97.

These trades were executed under a pre-arranged Rule 10b5-1 Trading Plan adopted on May 6, 2025, indicating they were scheduled in advance. Following the transactions, Parshall directly holds 51,344 shares of Ionis common stock.

Insider Trade Summary 10b5-1

Net Seller: 5,000 shares ($381,367)

Net Sell 2 txns

Insider PARSHALL B LYNNE

Role Director

Sold 5,000 shs ($381K)

Type	Security	Shares	Price	Value
Sale	Common Stock	4,466	$76.19	$340K
Sale	Common Stock	534	$76.97	$41K

Holdings After Transaction: Common Stock — 51,878 shares (Direct)

Footnotes (1)

Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on May 6, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $75.77 to $76.70 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 $76.85 to $77.115 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.

Key Figures

Shares sold: 5,000 shares First tranche sale price: $76.19/share Second tranche sale price: $76.97/share +3 more

6 metrics

Shares sold 5,000 shares Total common stock sold on April 15, 2026

First tranche sale price $76.19/share Weighted average for 4,466 shares sold

Second tranche sale price $76.97/share Weighted average for 534 shares sold

Shares held after transaction 51,344 shares Direct common stock holdings after sales

Transaction date April 15, 2026 Date of both reported open-market sales

Plan adoption date May 6, 2025 Adoption of Rule 10b5-1 Trading Plan

Key Terms

Rule 10b5-1 Trading Plan, weighted average price, open-market sale

3 terms

Rule 10b5-1 Trading Plan regulatory

"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.

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.

open-market sale financial

"transaction_action: "open-market sale" for common stock"

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

Form 4 Insider Transactions: What Each Field Means →

04/17/2026 - 07:19 PM

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).

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^*

PARSHALL B LYNNE

(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)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/15/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form 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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	04/15/2026		S		4,466⁽¹⁾	D	$76.19⁽²⁾	51,878	D
Common Stock	04/15/2026		S		534⁽¹⁾	D	$76.97⁽³⁾	51,344	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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on May 6, 2025.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $75.77 to $76.70 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 $76.85 to $77.115 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.

	By: Patrick R. O?Neil, attorney-in-fact For: B. Lynne Parshall	04/17/2026
	** 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.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transactions did IONIS (IONS) director Lynne Parshall report?

Director Lynne B. Parshall reported selling a total of 5,000 shares of Ionis common stock. The transactions were open-market sales executed on April 15, 2026, and were conducted under a pre-arranged Rule 10b5-1 Trading Plan adopted in May 2025.

At what prices were the IONIS (IONS) shares sold in this Form 4 filing?

The filing shows 4,466 shares sold at a weighted average price of $76.19 and 534 shares sold at a weighted average price of $76.97. Each line reflects multiple trades within narrow price ranges around those averages on April 15, 2026.

How many IONIS (IONS) shares does Lynne Parshall hold after these sales?

After the reported transactions, Lynne B. Parshall directly holds 51,344 shares of Ionis common stock. This post-transaction balance reflects the net position following the two open-market sales totaling 5,000 shares disclosed in the Form 4.

Were the IONIS (IONS) insider sales made under a Rule 10b5-1 plan?

Yes. The filing states the shares were sold pursuant to a Rule 10b5-1 Trading Plan adopted by Lynne B. Parshall on May 6, 2025. Such plans pre-schedule trades, indicating the timing was arranged in advance rather than decided spontaneously.

What does the weighted average price disclosure mean in the IONIS (IONS) Form 4?

Weighted average price means each reported price aggregates multiple trades executed at slightly different prices within a range. The filing notes ranges of $75.77–$76.70 and $76.85–$77.115 and offers to provide detailed per-trade data to Ionis, shareholders, or SEC staff upon request.