BIIB

BIOGEN INC.

Company with tickers: BIIB

CIK
875045
CUSIP
09062X103
Shares Outstanding
146,758,528

Short Interest History

Settlement Date Current Position Previous Position Change Days to Cover
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
2025-05-15 3,339,605 3,184,274 +155,331 1.93
2025-04-30 3,184,274 3,446,446 -262,172 2.17
2025-04-15 3,446,446 3,343,887 +102,559 1.68