Tweedy Browne's IONS Position Overview
Tweedy Browne (via Tweedy, Browne Co LLC) currently holds 1.79 M shares of Ionis Pharmaceuticals, Inc. (IONS) worth $80.08 M, representing 6.52% of the portfolio. First purchased in 2022-Q1, this medium-term investment has been held for 19 quarters.
Based on 13F filings, Tweedy Browne has maintained a strategic position in IONS, demonstrating sustained confidence in this investment. Largest addition occurred in Q4 2022, adding 818,148 shares. Largest reduction occurred in Q3 2026, reducing 486,911 shares.
Analysis based on 13F filings available since 2013 Q2
Tweedy Browne's Ionis Pharmaceuticals (IONS) Holding Value Over Time
Track share changes against reported price movement
Quarterly Ionis Pharmaceuticals (IONS) Trades by Tweedy Browne
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q3 2026 | -486,911 | Reduce 21.35% | 1.79 M | $44.65 |
| Q2 2026 | +4,686 | Add 0.21% | 2.28 M | $79.29 |
| Q1 2026 | -189,305 | Reduce 7.68% | 2.28 M | $75.09 |
| Q4 2025 | -436,286 | Reduce 15.04% | 2.46 M | $79.11 |
| Q3 2025 | +9,268 | Add 0.32% | 2.9 M | $65.42 |
| Q2 2025 | -91,570 | Reduce 3.07% | 2.89 M | $39.51 |
| Q1 2025 | -265,345 | Reduce 8.17% | 2.98 M | $30.17 |
| Q4 2024 | -205,813 | Reduce 5.96% | 3.25 M | $34.96 |
| Q4 2023 | -55,497 | Reduce 1.58% | 3.45 M | $50.59 |
| Q3 2023 | -30,685 | Reduce 0.87% | 3.51 M | $45.36 |
| Q2 2023 | -188 | Reduce 0.01% | 3.54 M | $41.03 |
| Q1 2023 | -90 | Reduce 0.00% | 3.54 M | $35.74 |
| Q4 2022 | +818,148 | Add 30.05% | 3.54 M | $37.77 |
| Q3 2022 | -3,790 | Reduce 0.14% | 2.72 M | $44.23 |
| Q2 2022 | -198,324 | Reduce 6.78% | 2.73 M | $37.02 |
| Q1 2022 | +2.93 M | New Buy | 2.93 M | $37.04 |
Tweedy Browne's Ionis Pharmaceuticals Investment FAQs
Tweedy Browne first purchased Ionis Pharmaceuticals, Inc. (IONS) in Q1 2022, acquiring 2,925,102 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Tweedy Browne has held Ionis Pharmaceuticals, Inc. (IONS) for 19 quarters since Q1 2022.
Tweedy Browne's largest addition to Ionis Pharmaceuticals, Inc. (IONS) was in Q1 2022, adding 2,925,102 shares worth $108.35 M.
According to the latest 13F filing for Q3 2026, Tweedy Browne's firm, Tweedy, Browne Co LLC, owns 1,793,400 shares of Ionis Pharmaceuticals, Inc. (IONS), valued at approximately $80.08 M.
As of the Q3 2026 filing, Ionis Pharmaceuticals, Inc. (IONS) represents approximately 6.52% of Tweedy Browne's publicly disclosed stock portfolio, making it one of their key holdings.
Tweedy Browne's peak holding in Ionis Pharmaceuticals, Inc. (IONS) was 3,541,136 shares, as reported at the end of Q4 2022.