OUR PURPOSE PIONEERING SCIENCE 121 ESG DATA TABLE BIOGEN 2021 YEAR IN REVIEW PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING Code Units 2018 2019 2020 2021 United Nations Global Compact Signatory or Participant   Workforce Disclosure Initiative (WDI) Signatory or Participant  Pharmaceutical Supply Chain Initiative Member Signatory or Participant   Compliance and Ethics Employees trained on Biogen’s Anti-Bribery and Corruption Policy % 100% 100% 100% 100% Employees trained on Biogen’s Code of Conduct % 100% 100% 100% 100% ENVIRONMENTAL 2,3 Climate Scope 1 (fossil fuels and refrigerants) 4 MT CO 2 e 68,448 67,031 57,553 63,182 Scope 2 – Market based (electricity and steam) 4 MT CO 2 e 61 131 280 268 Total Scope 1 & 2 (Market based) 4 MT CO 2 e 68,509 67,162 57,833 63,450 Scope 1 & 2 Intensity MTCO 2 e / MM USD revenue 5.1 4.7 4.3 5.8 Total Purchased Carbon Offsets 5 MT CO 2 e 76,642 76,667 29,637 0 Carbon Neutrality (Scope 1 & 2 – Offsets) MT CO 2 e 68,448 67,031 29,637 0 Scope 2 – Location based (electricity and steam) MT CO 2 e 37,347 37,712 36,953 34,262 Scope 3 6 MT CO 2 e 436,353 424,592 348,911 406,459 • Category 1 – Purchased goods and service MT CO 2 e 325,928 334,954 254,670 321,610 • Category 2 – Capital goods MT CO 2 e 51,635 32,759 41,356 34,506 • Category 3 – Fuel- and energy-related activities MT CO 2 e 11,048 10,570 8,755 11,791 • Category 4 – Upstream transportation and distribution MT CO 2 e N/A N/A 17,701 17,148 • Category 5 – Waste generated in operations 7 MT CO 2 e 758 645 487 290 • Category 6 – Business travel 8 MT CO 2 e 27,277 24,083 4,038 2,232 • Category 7 – Employee commuting 8 MT CO 2 e 8,133 9,516 2,661 2,227 • Category 7 – Employee work from home 8 MT CO 2 e N/A N/A 9,531 9,652 • Category 8 – Upstream leased assets MT CO 2 e 0 0 0 0 • Category 12 – End-of-life treatment of sold products MT CO 2 e 11,574 12,065 9,141 7,003 Scope 3 Intensity 9 MT CO 2 e / MM USD revenue 32 30 26 37 Scope 3 (percent of Scope 1, 2 & 3) % 86 86 86 86 Total Value Chain (Scope 1, 2 & 3) 4 MT CO 2 e 504,862 491,545 406,139 469,909