Ionis Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US4622221004

SecurityIONS / Ionis Pharmaceuticals, Inc.
InstitutionTrexquant Investment LP
Latest Disclosed Ownership213,645 shares
Latest Disclosed Value $ 16,042,603
Trexquant Investment LP reports 61.56% increase in ownership of IONS / Ionis Pharmaceuticals, Inc.

On May 15, 2026 - Trexquant Investment LP filed a 13F-HR form disclosing ownership of 213,645 shares of Ionis Pharmaceuticals, Inc. (US:IONS) valued at $16,042,603 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 132,241 shares of Ionis Pharmaceuticals, Inc.. This represents a change in shares of 61.56% during the quarter. The current value of the position is $15,912,280 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)
2026-05-15 2026-03-31 13F IONIS PHARMACEUTICALS COM 462222100 213,645 81,404 61.56 16,043 53.35 0.1153
2026-02-17 2025-12-31 13F IONIS PHARMACEUTICALS COM 462222100 132,241 -82,880 -38.53 10,462 -25.67 0.0933
2025-11-14 2025-09-30 13F IONIS PHARMACEUTICALS COM 462222100 215,121 86,252 66.93 14,073 176.43 0.1449
2025-08-12 2025-06-30 13F IONIS PHARMACEUTICALS COM 462222100 128,869 128,869 5,092 0.0574
2025-05-14 2025-03-31 13F IONIS PHARMACEUTICALS COM 462222100 0 -84,913 -100.00 0 -100.00
2025-02-12 2024-12-31 13F IONIS PHARMACEUTICALS COM 462222100 84,913 -45,945 -35.11 2,969 -43.38 0.0346
2024-11-12 2024-09-30 13F IONIS PHARMACEUTICALS COM 462222100 130,858 100,772 334.95 5,242 265.81 0.0664
2024-08-13 2024-06-30 13F IONIS PHARMACEUTICALS COM 462222100 30,086 -55,266 -64.75 1,434 -61.27 0.0219
2024-05-14 2024-03-31 13F IONIS PHARMACEUTICALS COM 462222100 85,352 -27,635 -24.46 3,700 -35.27 0.0738
2024-02-09 2023-12-31 13F IONIS PHARMACEUTICALS COM 462222100 112,987 -70,362 -38.38 5,716 -31.27 0.1286
2023-11-13 2023-09-30 13F IONIS PHARMACEUTICALS COM 462222100 183,349 78,724 75.24 8,317 93.76 0.2087
2023-08-11 2023-06-30 13F IONIS PHARMACEUTICALS COM 462222100 104,625 72,013 220.82 4,293 268.41 0.1125
2023-05-15 2023-03-31 13F IONIS PHARMACEUTICALS COM 462222100 32,612 -14,333 -30.53 1,166 -34.29 0.0320
2023-02-13 2022-12-31 13F IONIS PHARMACEUTICALS COM 462222100 46,945 -8,619 -15.51 1,773 -27.87 0.0503
2022-11-14 2022-09-30 13F IONIS PHARMACEUTICALS COM 462222100 55,564 27,141 95.49 2,458 133.65 0.0864
2022-08-11 2022-06-30 13F IONIS PHARMACEUTICALS COM 462222100 28,423 -19,339 -40.49 1,052 -40.53 0.0471
2022-05-13 2022-03-31 13F IONIS PHARMACEUTICALS COM 462222100 47,762 13,859 40.88 1,769 71.41 0.0831
2022-02-14 2021-12-31 13F IONIS PHARMACEUTICALS COM 462222100 33,903 20,606 154.97 1,032 131.39 0.0638
2021-11-12 2021-09-30 13F IONIS PHARMACEUTICALS COM 462222100 13,297 13,297 446 0.0354
2020-11-06 2020-09-30 13F IONIS PHARMACEUTICALS COM 462222100 0 -29,759 -100.00 0 -100.00
2020-08-07 2020-06-30 13F IONIS PHARMACEUTICALS COM 462222100 29,759 -17,740 -37.35 1,755 -21.86 0.1219
2020-05-08 2020-03-31 13F IONIS PHARMACEUTICALS COM 462222100 47,499 47,499 2,246 0.1630
2020-02-14 2019-09-30 13F/A-1 IONIS PHARMACEUTICALS COM 462222100 0 -11,383 -100.00 0 -100.00
2019-08-09 2019-06-30 13F IONIS PHARMACEUTICALS COM 462222100 11,383 -19,298 -62.90 732 -70.60 0.0659
2019-05-13 2019-03-31 13F IONIS PHARMACEUTICALS COM 462222100 30,681 30,681 2,490 0.1768
2017-11-09 2017-09-30 13F IONIS PHARMACEUTICALS COM 462222100 0 -4,580 -100.00 0 -100.00
2017-08-01 2017-06-30 13F IONIS PHARMACEUTICALS COM 462222100 4,580 -2,320 -33.62 233 -15.88 0.0638
2017-05-08 2017-03-31 13F IONIS PHARMACEUTICALS COM 462222100 6,900 6,900 277 0.0355
2016-05-11 2016-03-31 13F IONIS PHARMACEUTICALS COM 462222100 0 -13,500 -100.00 0 -100.00
2016-02-10 2015-12-31 13F IONIS PHARMACEUTICALS COM 462222100 13,500 13,500 836 0.0736
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.