OUR PURPOSE PIONEERING SCIENCE 125 ESG DATA TABLE BIOGEN 2021 YEAR IN REVIEW PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING Code Units 2018 2019 2020 2021 Demographics in Workforce (U.S. Only) • Asian American % N/A N/A 16.9 17.4 • Black or African American % N/A N/A 12.2 11.6 • Hispanic or Latino % N/A N/A 5.1 4.8 • White % N/A N/A 63.4 63.6 • Indigenous or Native American % N/A N/A 0.3 0.4 • Native Hawaiian or Other Pacific Islander % N/A N/A 0.1 0.1 • Two or More Races % N/A N/A 1.1 1.5 • No Response % N/A N/A 0.5 0.6 Demographics in Management (U.S. Only) 30 • Asian American % N/A N/A 18.5 19.5 • Black or African American % N/A N/A 5.3 6.6 • Hispanic or Latino % N/A N/A 4.9 4.7 • White % N/A N/A 69.4 67.1 • Indigenous or Native American % N/A N/A 0.1 0.2 Other Underrepresented Groups • People with Disability in Workforce % N/A N/A 3.3 3.7 • LGBTQ+ in Workforce % N/A N/A 1.6 1.3 • Workforce Age 29 or Younger % N/A N/A 9.8 8.5 • Workforce Age 30 to 50 % N/A N/A 67.8 67.8 • Workforce Age 51 or Older % N/A N/A 22.5 23.7 Demographics in Board of Directors 31 • Black or African American # N/A N/A N/A 1 • Hispanic or Latino # N/A N/A N/A 2 • White # N/A N/A N/A 9 • Did Not Disclose Demographic Background # N/A N/A N/A 1 Director-level and Above Positions Held by Racial Minorities (U.S. Only) % N/A 26 28 26