BIIB
Biogen Inc.Company with tickers: BIIB
CIK
875045
CUSIP
09062X103
Shares Outstanding
147,637,117
13F Activity (30d)
685 filings
673 filers
Short Interest History
| Settlement Date | Current Position | Previous Position | Change | Days to Cover |
|---|---|---|---|---|
| 2026-05-15 | 4,729,958 | 4,475,470 | +254,488 | 4.21 |
| 2026-04-30 | 4,475,470 | 4,414,958 | +60,512 | 3.59 |
| 2026-04-15 | 4,414,958 | 3,826,441 | +588,517 | 3.07 |
| 2026-03-31 | 3,826,441 | 4,334,795 | -508,354 | 3.47 |
| 2026-03-13 | 4,334,795 | 4,202,912 | +131,883 | 5.15 |
| 2026-02-27 | 4,202,912 | 4,545,171 | -342,259 | 4.63 |
| 2026-02-13 | 4,545,171 | 4,692,637 | -147,466 | 2.45 |
| 2026-01-30 | 4,692,637 | 4,678,036 | +14,601 | 3.62 |
| 2026-01-15 | 4,678,036 | 4,466,337 | +211,699 | 2.62 |
| 2025-12-31 | 4,466,337 | 6,590,958 | -2,124,621 | 1.67 |
| 2025-12-15 | 6,590,958 | 6,777,473 | -186,515 | 3.67 |
| 2025-11-28 | 6,777,473 | 6,140,844 | +636,629 | 3.26 |
| 2025-11-14 | 6,140,844 | 5,644,654 | +496,190 | 3.19 |
| 2025-10-31 | 5,644,654 | 5,191,008 | +453,646 | 3.60 |
| 2025-10-15 | 5,191,008 | 4,880,043 | +310,965 | 2.69 |
| 2025-09-30 | 4,880,043 | 5,125,778 | -245,735 | 2.98 |
| 2025-09-15 | 5,125,778 | 4,720,975 | +404,803 | 3.01 |
| 2025-08-29 | 4,720,975 | 4,155,186 | +565,789 | 3.58 |
| 2025-08-15 | 4,155,186 | 3,959,672 | +195,514 | 2.68 |
| 2025-07-31 | 3,959,672 | 3,896,146 | +63,526 | 2.78 |
| 2025-07-15 | 3,896,146 | 4,000,596 | -104,450 | 3.23 |
| 2025-06-30 | 4,000,596 | 3,389,242 | +611,354 | 3.07 |
| 2025-06-13 | 3,389,242 | 3,795,285 | -406,043 | 2.57 |
| 2025-05-30 | 3,795,285 | 3,339,605 | +455,680 | 2.13 |