Filing of financial statements requires prescribed e-forms, XBRL where mandated, and CSR disclosures as addenda. Rule 12 requires companies to file financial statements with the Registrar using prescribed e forms-Form AOC-4 for standalone statements and Form AOC-4 CFS for consolidated statements-with NBFCs under Ind AS using designated NBFC e forms; CSR-2 must be furnished as an addendum or separately per transitional timelines, mandatory XBRL filing may be notified by the Central Government, and applicable fees are as specified in the Companies (Registration Offices and Fees) Rules, 2014.