US Trade Act authority for additional duties in response to unfair foreign trade practices.
Section 301 of the Trade Act of 1974 authorizes the US Trade Representative to impose additional duties on goods from a country found to be engaging in unfair trade practices. It is the legal basis for the tariff "lists" applied to Chinese-origin goods since 2018, and has since been used for narrower actions targeting specific practices — including a forced-labor-linked action and a more recent action on Chinese maritime/shipping equipment. A Section 301 duty is additive: it stacks on top of the MFN base rate rather than replacing it, and specific products can carry an exclusion that suspends the duty for a defined period.
Trade Act of 1974, 19 U.S.C. 2411, implemented via USTR Federal Register notices and HTSUS Chapter 99 headings (9903.88.xx / 9903.91.xx and related).
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