EPA has finalized a rule under the Toxic Substances Control Act (TSCA) to amend the Chemical Data Reporting (CDR) rule. The CDR rule, under TSCA section 8(a), requires manufacturers (including importers) of certain chemical substances listed on the TSCA Chemical Substance Inventory (TSCA Inventory) to report data on chemical manufacturing, processing, and use every four years. EPA finalized several changes to the CDR rule that were proposed in April 2019 to make regulatory updates that align with new statutory requirements of TSCA to improve the CDR data collected as necessary to support the implementation of TSCA, and potentially to reduce burden for certain CDR reporters. In addition, these regulatory modifications may result in additional information to EPA and the public that is currently not collected; improve the usability and reliability of the reported data; and ensure that data are available in a timely manner. The CDR Revisions were proposed along with updates to the TSCA section 8(a) size standards for small manufacturers in one notice. EPA is finalizing the size standard updates in a separate action (RIN 2070-AK57).