On January 19, 2017, the U.S. Environmental Protection Agency (EPA) issued an interpretation of Toxic Substances Control Act (TSCA) Section 14 concerning confidential business information (CBI) claims for information submitted to EPA.  82 Fed. Reg. 6522.  Under the interpretation, EPA expresses its view that new TSCA requires substantiation of all non-exempt CBI claims at the time the information claimed as confidential is submitted to EPA.  In the notice, EPA also states that the action will “facilitate [its] implementation of TSCA section 14(g) to review all CBI claims for chemical identity, with limited exceptions, as well as to review a representative sample of at least 25% of other non-exempt claims.”  Information that is (or will be) submitted and claimed as CBI between June 22, 2016, and March 19, 2017 (inclusive), must be substantiated by September 19, 2017.  CBI claims made as part of an existing submission in EPA’s Central Data Exchange (CDX), such as a premanufacture notice (PMN), must be substantiated by amending the CDX submission.  Other information should be substantiated using the same mechanism (e.g., substantiate claims made on paper by submitting substantiations on paper).  This action will become effective on March 20, 2017.