IONS short interest
Ionis Pharmaceuticals Inc. · Healthcare · Biotechnology · settlement date 2026-09-30
| Shares short | 22,508,744 |
|---|---|
| Change vs prior report | 1,618,492 (+7.8%) |
| Change over six months | +57.1% |
| Days to cover | 4.61 (sector: 3.78) |
| Average daily volume | 4,881,042 |
| Rank in Healthcare | #454 of 922 by days to cover |
IONS short interest, last 12 months
| Settlement | Shares short | Change | Days to cover | Avg daily volume |
|---|---|---|---|---|
| 2026-09-30 | 22,508,744 | +7.8% | 4.61 | 4,881,042 |
| 2026-09-15 | 20,890,252 | -0.2% | 5.20 | 4,017,153 |
| 2026-08-31 | 20,924,638 | +0.1% | 9.18 | 2,279,069 |
| 2026-08-14 | 20,909,181 | -2.6% | 9.62 | 2,172,496 |
| 2026-07-31 | 21,466,123 | +7.1% | 6.35 | 3,382,861 |
| 2026-07-15 | 20,042,879 | +15.0% | 3.68 | 5,450,805 |
| 2026-06-30 | 17,425,020 | -1.9% | 7.33 | 2,377,735 |
| 2026-06-15 | 17,757,362 | +4.5% | 10.64 | 1,668,579 |
| 2026-05-29 | 16,986,466 | +5.6% | 9.98 | 1,702,170 |
| 2026-05-15 | 16,086,234 | -1.2% | 10.00 | 1,608,774 |
| 2026-04-30 | 16,279,706 | +18.3% | 8.04 | 2,023,751 |
| 2026-04-15 | 13,762,159 | -4.0% | 9.54 | 1,443,237 |
| 2026-03-31 | 14,330,826 | +2.7% | 5.93 | 2,418,365 |
| 2026-03-13 | 13,949,702 | -9.0% | 5.68 | 2,453,957 |
| 2026-02-27 | 15,323,236 | -1.1% | 6.91 | 2,217,431 |
| 2026-02-13 | 15,487,922 | -0.3% | 8.37 | 1,851,249 |
| 2026-01-30 | 15,537,729 | +13.2% | 5.82 | 2,668,640 |
| 2026-01-15 | 13,729,783 | -7.8% | 6.59 | 2,082,127 |
| 2025-12-31 | 14,885,370 | -7.5% | 9.49 | 1,568,746 |
| 2025-12-15 | 16,086,183 | +2.9% | 7.96 | 2,020,355 |
| 2025-11-28 | 15,626,208 | +9.9% | 5.95 | 2,624,122 |
| 2025-11-14 | 14,223,973 | +12.3% | 3.81 | 3,736,097 |
| 2025-10-31 | 12,661,274 | -7.6% | 6.61 | 1,914,799 |
| 2025-10-15 | 13,699,358 | +11.6% | 6.01 | 2,279,250 |
| 2025-09-30 | 12,278,792 | +2.6% | 6.16 | 1,991,945 |
import finzdata as yf
yf.Ticker("IONS").short_interest # every report since 2017
yf.Client().short_interest(["IONS"], start="2018-01-01")Healthcare short interest · IONS price history · Who owns IONS · All short interest