Short interest in Biogen Inc (NASDAQ:BIIB) increased during the last reporting period, rising from 3.07M to 3.12M. This put 2.42% of the company's publicly available shares short.

Short interest for Biogen gives investors a sense of the degree to which investors are betting on the decline of Biogen's stock. Short interest data is updated every two weeks.

Based on the recent average volume of 1.24M shares traded per day, it would take 2.52 day(s) for holders of this short interest to close out their positions without sending the stock sharply higher.