Ionis Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US4622221004

SecurityIONS / Ionis Pharmaceuticals, Inc.
InstitutionPinnacle Associates Ltd
Latest Disclosed Ownership436,457 shares
Latest Disclosed Value $ 32,773,556
Pinnacle Associates Ltd reports 5.52% decrease in ownership of IONS / Ionis Pharmaceuticals, Inc.

On April 21, 2026 - Pinnacle Associates Ltd filed a 13F-HR form disclosing ownership of 436,457 shares of Ionis Pharmaceuticals, Inc. (US:IONS) valued at $32,773,556 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 461,968 shares of Ionis Pharmaceuticals, Inc.. This represents a change in shares of -5.52% during the quarter. The current value of the position is $32,219,256 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-04-21 2026-03-31 13F IONIS PHARMACEUTICALS COM 462222100 436,457 -25,511 -5.52 32,774 -10.32 0.4201
2026-02-05 2025-12-31 13F IONIS PHARMACEUTICALS COM 462222100 461,968 -19,783 -4.11 36,546 15.96 0.4689
2025-11-13 2025-09-30 13F IONIS PHARMACEUTICALS COM 462222100 481,751 -12,788 -2.59 31,516 61.30 0.4182
2025-08-04 2025-06-30 13F IONIS PHARMACEUTICALS COM 462222100 494,539 -113,978 -18.73 19,539 6.43 0.2829
2025-05-06 2025-03-31 13F IONIS PHARMACEUTICALS COM 462222100 608,517 60,875 11.12 18,359 -4.11 0.2690
2025-02-14 2024-12-31 13F IONIS PHARMACEUTICALS COM 462222100 547,642 88,663 19.32 19,146 -17.55 0.2598
2024-10-25 2024-09-30 13F IONIS PHARMACEUTICALS COM 462222100 458,979 5,600 1.24 23,220 7.46 0.3948
2024-07-30 2024-06-30 13F IONIS PHARMACEUTICALS COM 462222100 453,379 -6,379 -1.39 21,608 8.42 0.3383
2024-04-26 2024-03-31 13F IONIS PHARMACEUTICALS COM 462222100 459,758 779 0.17 19,931 -14.17 0.3141
2024-01-19 2023-12-31 13F IONIS PHARMACEUTICALS COM 462222100 458,979 -4,056 -0.88 23,220 10.55 0.3907
2023-10-24 2023-09-30 13F IONIS PHARMACEUTICALS COM 462222100 463,035 -15,169 -3.17 21,003 7.05 0.3904
2023-07-27 2023-06-30 13F IONIS PHARMACEUTICALS COM 462222100 478,204 -12,451 -2.54 19,621 11.88 0.3405
2023-05-05 2023-03-31 13F IONIS PHARMACEUTICALS COM 462222100 490,655 -4,095 -0.83 17,536 -6.15 0.3587
2023-02-01 2022-12-31 13F/A-1 IONIS PHARMACEUTICALS COM 462222100 494,750 -6,140 -1.23 18,687 -15.65 0.4072
2023-01-25 2022-12-31 13F IONIS PHARMACEUTICALS COM 462222100 493,095 -7,795 20,493 0.0004
2022-11-01 2022-09-30 13F IONIS PHARMACEUTICALS COM 462222100 500,890 -14,969 -2.90 22,154 16.01 0.5085
2022-08-02 2022-06-30 13F IONIS PHARMACEUTICALS COM 462222100 515,859 -6,109 -1.17 19,097 -1.23 0.4164
2022-05-05 2022-03-31 13F IONIS PHARMACEUTICALS COM 462222100 521,968 -19,076 -3.53 19,334 17.43 0.3422
2022-02-02 2021-12-31 13F IONIS PHARMACEUTICALS COM 462222100 541,044 -2,182 -0.40 16,464 -9.64 0.2840
2021-10-19 2021-09-30 13F IONIS PHARMACEUTICALS COM 462222100 543,226 1,884 0.35 18,220 -15.62 0.3359
2021-08-02 2021-06-30 13F IONIS PHARMACEUTICALS COM 462222100 541,342 28,218 5.50 21,594 -6.40 0.3904
2021-05-12 2021-03-31 13F IONIS PHARMACEUTICALS COM 462222100 513,124 -40,790 -7.36 23,070 -26.34 0.4399
2021-01-26 2020-12-31 13F IONIS PHARMACEUTICALS COM 462222100 553,914 -28,955 -4.97 31,318 13.24 0.6359
2020-10-23 2020-09-30 13F IONIS PHARMACEUTICALS COM 462222100 582,869 -18,828 -3.13 27,657 -22.04 0.6569
2020-08-14 2020-06-30 13F IONIS PHARMACEUTICALS COM 462222100 601,697 -20,212 -3.25 35,476 20.65 0.8748
2020-05-13 2020-03-31 13F IONIS PHARMACEUTICALS COM 462222100 621,909 -80,650 -11.48 29,404 -30.72 0.8932
2020-02-03 2019-12-31 13F IONIS PHARMACEUTICALS COM 462222100 702,559 -65,401 -8.52 42,442 -7.75 0.9294
2019-11-08 2019-09-30 13F IONIS PHARMACEUTICALS COM 462222100 767,960 -32,308 -4.04 46,008 -10.55 1.0837
2019-08-05 2019-06-30 13F IONIS PHARMACEUTICALS COM 462222100 800,268 -77,763 -8.86 51,433 -27.83 1.2043
2019-05-10 2019-03-31 13F IONIS PHARMACEUTICALS COM 462222100 878,031 -30,915 -3.40 71,270 45.04 1.6101
2019-02-05 2018-12-31 13F IONIS PHARMACEUTICALS COM 462222100 908,946 -61,119 -6.30 49,138 -1.79 1.2686
2018-11-09 2018-09-30 13F IONIS PHARMACEUTICALS COM 462222100 970,065 -123,033 -11.26 50,036 9.85 1.0381
2018-08-08 2018-06-30 13F IONIS PHARMACEUTICALS COM 462222100 1,093,098 -150,877 -12.13 45,549 -16.93 0.9371
2018-05-11 2018-03-31 13F IONIS PHARMACEUTICALS COM 462222100 1,243,975 -45,246 -3.51 54,834 -15.44 1.0746
2018-02-12 2017-12-31 13F IONIS PHARMACEUTICALS COM 462222100 1,289,221 -109,244 -7.81 64,848 -8.54 1.2459
2017-11-13 2017-09-30 13F IONIS PHARMACEUTICALS COM 462222100 1,398,465 -48,099 -3.33 70,902 -3.65 1.3071
2017-08-09 2017-06-30 13F IONIS PHARMACEUTICALS COM 462222100 1,446,564 -68,146 -4.50 73,587 20.85 1.4143
2017-05-09 2017-03-31 13F IONIS PHARMACEUTICALS COM 462222100 1,514,710 -57,335 -3.65 60,891 -19.02 1.1629
2017-02-10 2016-12-31 13F IONIS PHARMACEUTICALS COM 462222100 1,572,045 -83,972 -5.07 75,191 23.92 1.5171
2016-11-14 2016-09-30 13F IONIS PHARMACEUTICALS COM 462222100 1,656,017 -24,395 -1.45 60,676 55.03 1.2170
2016-08-15 2016-06-30 13F IONIS PHARMACEUTICALS COM 462222100 1,680,412 -16,966 -1.00 39,137 -43.07 0.8434
2016-05-13 2016-03-31 13F IONIS PHARMACEUTICALS COM 462222100 1,697,378 7,115 0.42 68,744 -34.33 1.4705
2016-02-11 2015-12-31 13F/A-1 IONIS PHARMACEUTICALS COM 462222100 1,690,263 -88,062 -4.95 104,678 45.63 2.1962
2016-02-09 2015-12-31 13F IONIS PHARMACEUTICALS COM 462222100 1,690,263 -88,062 104,678 2.2368
2015-11-10 2015-09-30 13F ISIS PHARMACEUTICALS COM 464330109 1,778,325 -50,553 -2.76 71,880 -31.71 1.5904
2015-08-12 2015-06-30 13F ISIS PHARMACEUTICALS COM 464330109 1,828,878 -60,139 -3.18 105,252 -12.49 1.9540
2015-05-15 2015-03-31 13F ISIS Pharmaceuticals COM 464330109 1,889,017 -28,821 -1.50 120,274 1.58 2.2442
2015-02-12 2014-12-31 13F ISIS Pharmaceuticals COM 464330109 1,917,838 72,111 3.91 118,407 65.21 2.3217
2014-11-12 2014-09-30 13F ISIS Pharmaceuticals COM 464330109 1,845,727 -69,215 -3.61 71,670 8.64 1.4593
2014-08-14 2014-06-30 13F ISIS Pharmaceuticals COM 464330109 1,914,942 -25,722 -1.33 65,970 -21.33 1.2877
2014-05-14 2014-03-31 13F ISIS Pharmaceuticals COM 464330109 1,940,664 -75,705 -3.75 83,856 4.39 1.6353
2014-02-12 2013-12-31 13F ISIS Pharmaceuticals COM 464330109 2,016,369 -48,391 -2.34 80,332 3.64 1.5685
2013-11-14 2013-09-30 13F ISIS Pharmaceuticals COM 464330109 2,064,760 -54,603 -2.58 77,511 36.11 1.6035
2013-08-13 2013-06-30 13F ISIS Pharmaceuticals COM 464330109 2,119,363 2,119,363 56,947 1.2798
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.