This document adopts as final, with changes, interim amendments to the U.S. Customs and Border Protection (CBP) regulations that were published in the Federal Register on August 22, 2016, as CBP Dec. 16-11, which implemented procedures to investigate claims of evasion of antidumping and countervailing duty (AD/CVD) orders in accordance with section 421 of the Trade Facilitation and Trade Enforcement Act of 2015. This document also announces that CBP deployed a case management system in April 2021, which CBP and the public use for filing, tracking, and adjudicating allegations of evasion of AD/CVD orders.