Biogen Inc. short interest
Short interest in Biogen Inc. was 5.7 million shares at the 31 August 2026 settlement, up 10.3% on the previous settlement, with 8.66 days to cover at an average daily volume of 661,593 shares, as reported to FINRA.
| Settlement | Shares short | Change | Average daily volume | Days to cover |
|---|---|---|---|---|
| 31 August 2026 | 5,726,631 | +10.3% | 661,593 | 8.66 |
| 14 August 2026 | 5,190,555 | -4.8% | 847,068 | 6.13 |
| 31 July 2026 | 5,453,901 | -9.1% | 1,153,245 | 4.73 |
| 15 July 2026 | 5,999,133 | +4.8% | 1,739,800 | 3.45 |
| 30 June 2026 | 5,723,194 | +10.3% | 1,382,477 | 4.14 |
| 15 June 2026 | 5,188,836 | +8.8% | 918,726 | 5.65 |
| 29 May 2026 | 4,771,495 | +0.9% | 1,063,313 | 4.49 |
| 15 May 2026 | 4,729,958 | +5.7% | 1,122,410 | 4.21 |
| 30 April 2026 | 4,475,470 | +1.4% | 1,247,291 | 3.59 |
| 15 April 2026 | 4,414,958 | +15.4% | 1,439,919 | 3.07 |
| 31 March 2026 | 3,826,441 | -11.7% | 1,104,246 | 3.47 |
| 13 March 2026 | 4,334,795 | +3.1% | 842,122 | 5.15 |
FINRA publishes consolidated short interest twice a month, about ten days after each settlement. Days to cover is shares short over average daily volume. Short interest as a share of the float is not shown: the float is not in the public record.
Source
FINRA equity short interest data, the public dataset.
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