<SEC-DOCUMENT>0000874015-25-000260.txt : 20251016
<SEC-HEADER>0000874015-25-000260.hdr.sgml : 20251016
<ACCEPTANCE-DATETIME>20251016201608
ACCESSION NUMBER:		0000874015-25-000260
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251015
FILED AS OF DATE:		20251016
DATE AS OF CHANGE:		20251016

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Devers Shannon L.
		CENTRAL INDEX KEY:			0002037721
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19125
		FILM NUMBER:		251398755

	MAIL ADDRESS:	
		STREET 1:		C/O IONIS PHARMACEUTICALS, INC.
		STREET 2:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IONIS PHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0000874015
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				330336973
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010
		BUSINESS PHONE:		7609319200

	MAIL ADDRESS:	
		STREET 1:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ISIS PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	19930328
</SEC-HEADER>
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            <rptOwnerName>Devers Shannon L.</rptOwnerName>
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    <footnotes>
        <footnote id="F1">Shares sold pursuant to a Rule 10b5-1 Trading Plan adopted by the reporting person on September 3, 2024.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $72.775 to $73.04 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.</footnote>
        <footnote id="F3">Acquired pursuant to vesting and release of shares in accordance with a Restricted Stock Unit award.</footnote>
        <footnote id="F4">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.</footnote>
        <footnote id="F5">Each Restricted Stock Unit represents a contingent right to receive one share of Ionis common stock, or its equivalent cash value.</footnote>
        <footnote id="F6">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.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Patrick R. O'Neil, attorney-in-fact For: Shannon L. Devers</signatureName>
        <signatureDate>2025-10-16</signatureDate>
    </ownerSignature>
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