OUR PURPOSE PIONEERING SCIENCE 136 GRI CONTENT INDEX BIOGEN 2021 YEAR IN REVIEW PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING GRI indicator Reporting Requirements 2021 Response Alignment SDG 102–55 a. The GRI content index, which specifies each of the GRI Standards used and lists all disclosures included in the report. b. For each disclosure, the content index shall include: • The number of the disclosure (for disclosures covered by the GRI Standards). • The page number(s) or URL(s) where the information can be found, either within the report or in other published materials. • If applicable, and where permitted, the reason(s) for omission when a required disclosure cannot be made. Additional requirements for compiling: 6.3 When reporting the GRI content index as specified in Disclosure 102–55, the reporting organization shall: 6.3.1 Include the words ’GRI Content Index’ in the title. 6.3.2 Present the complete GRI content index in one location. 6.3.3 Include in the report a link or reference to the GRI content index, if it is not provided in the report itself. 6.3.4 For each GRI Standard used, include the title and publication year (e.g., GRI 102: General Disclosures 2016). 6.3.5 Include any additional material topics reported on which are not covered by the GRI Standards, including page number(s) or URL(s) where the information can be found. GRI Content Index 102–56 a. A description of the organization’s policy and current practice with regard to seeking external assurance for the report. b. If the report has been externally assured: • A reference to the external assurance report, statements or opinions. If not included in the assurance report accompanying the sustainability report, a description of what has and what has not been assured and on what basis, including the assurance standards used, the level of assurance obtained, and any limitations of the assurance process. • The relationship between the organization and the assurance provider. • Whether and how the highest governance body or senior executives are involved in seeking external assurance for the organization’s sustainability report. Independent Assurance Statement to Biogen Inc.