As Of	Filer	Filing¹	For·On·As	Docs:Size	Issuer		Filing Agent

  2/9/21  Posner Brian S                    5          Director²   1:4K   Biogen Inc.                       Computershare Inc.       
  2/9/21  Pangia Robert W                   5          Director²   1:5K   Biogen Inc.                       Computershare Inc.       
  2/3/21  Biogen Inc.                       10-K       12/31/20  163:30M                                                             
 1/11/21  Biogen Inc.                       3          10% Owner²  1:5K   Sage Therapeutics, Inc.           Donnelley Fin’l S… 06/FA 
          Biogen MA Inc.

____________
¹	Filing/Form Types:  -U
	3	Initial Statement of Beneficial Ownership of Securities by an Insider — Form 3 { The Filer is an Insider² of the Issuer }.
	5	Annual Statement of Changes in Beneficial Ownership of Securities by an Insider — Form 5 { The Filer is an Insider² of the Issuer }.
	10-K	Annual Report — Form 10-K.
²	Insider:  The Filer is a Director, Officer, 10% Owner and/or Other “insider” of the Issuer.