OUR PURPOSE PIONEERING SCIENCE PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING 12 BIOGEN 2021 YEAR IN REVIEW ESG governance and strategy Guided by our purpose, Biogen is committed to leadership across all material aspects of environmental, social and governance (ESG) issues. Following Biogen’s Corporate Governance Principles, the Board of Directors has oversight related to ESG matters. Management provides updates to our Board of Directors on relevant ESG efforts, and understanding the importance of ESG performance and disclosure, the Board and/or Board members meet with Biogen stakeholders on relevant issues. Our Board regularly reviews its composition to ensure it includes directors with the experience, skills and diversity necessary for effective, independent Board oversight. The skills matrix for Directors includes diversity of personal background and ESG experience and competence. In 2022, as part of our commitment, Biogen once again tied a portion of our employees’ and executive officers’ compensation to advancing our ESG strategy. Our commitment is grounded in our mission to transform patients’ lives by pioneering and leading in neuroscience. Working strategically and ethically, we seek to unlock promising scientific breakthroughs that have the potential to impact the lives of patients around the world, through a variety of initiatives designed to promote health access and equity and to reduce our operational impact on the environment. We believe our governance structures and processes, including our ESG materiality assessment, can strengthen stakeholder relations and help ensure accountability. We believe that the organizations that deliver the greatest long-term success consider a broad array of stakeholder needs as part of their corporate strategy and operations. We are responding to stakeholder interests through increasing transparency across our ESG efforts, including aligning this report with evolving reporting frameworks such as Sustainability Accounting Standards Board (SASB) and the Stakeholder Capitalism Metrics, originally unveiled at the World Economic Forum. We acknowledge the call from investors to better understand climate-related financial risks and with this document are publishing our second disclosure aligned with the Task Force on Climate-related Financial Disclosures (TCFD). Not only is Biogen a signatory of the United Nations Global Compact, this year we are pleased to be an early adopter of its new reporting standards. With this Year in Review, we are pleased to report on our purpose- driven performance on material ESG issues and 2021 highlights across our key priorities.