The Environmental Protection Agency (EPA) is finalizing new and amended requirements concerning the assertion and treatment of confidential business information (CBI) claims for information reported to or otherwise obtained by EPA under the Toxic Substances Control Act (TSCA). Amendments to TSCA in 2016 included many new provisions concerning the assertion, Agency review, and treatment of confidentiality claims. This document finalizes procedures for submitting such claims in TSCA submissions. It addresses issues such as substantiation requirements, exemptions, electronic reporting enhancements (including expanding electronic reporting requirements), maintenance or withdrawal of confidentiality claims, and provisions in current rules that are inconsistent with amended TSCA. The rule also addresses EPA procedures for reviewing and communicating with TSCA submitters about confidentiality claims.