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        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>O'NEIL PATRICK R.</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
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            <com:city>New Jersey</com:city>
            <com:stateOrCountry>NJ</com:stateOrCountry>
            <com:zipCode>07311</com:zipCode>
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        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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      <noticeSignature>
        <noticeDate>02/06/2023</noticeDate>
        <signature>Patrick R. O'Neil</signature>
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text: 144
  0001564926
  XXXXXXXX
  LIVE
  0000874015
  IONIS PHARMACEUTICALS INC
  000-19125
  2855 GAZELLE COURT
  CARLSBAD
  CA
  92010
  7609319200
  O'NEIL PATRICK R.
  Officer
  Common Stock
  ETrade by Morgan Stanley
  200 Hudson Street, Suite 501
  New Jersey
  NJ
  07311
  1920
  78123.33
  142050000
  02/06/2023
  NASDAQ
  Common
  02/03/2023
  PRSUs granted under the 2011 Equity Incentive Plan
  Ionis Pharmacueticals
  N
  1920
  02/03/2023
  Services rendered
  N
  Patrick R. O'Neil
  2855 Gazelle Court
  Carlsbad
  CA
  92010
  Common
  01/18/2023
  7836
  309480.00
  Patrick R. O'Neil
  2855 Gazelle Court
  Carlsbad
  CA
  92010
  Common
  01/30/2023
  4500
  177372.00
  Patrick R. O'Neil
  2855 Gazelle Court
  Carlsbad
  CA
  92010
  Common
  01/31/2023
  4500
  178669.95
  02/06/2023
  Patrick R. O'Neil