Section 338 of the Tariff Act of 1930 (19 U.S.C. § 1338) authorizes the President to impose new or additional duties of up to 50% ad valorem on imports — or exclude them from entry entirely — from any country that discriminates against U.S. commerce in a way that places it at a disadvantage compared with the commerce of any foreign country.
The statute identifies two categories of discrimination:
- Subsection (a) — Imposing duties or restrictions on U.S. goods that aren't applied to like goods from other countries, in a way that places U.S. commerce at a disadvantage
- Subsection (b) — Discriminating in fact against U.S. commerce by law or administrative regulation, in any manner
Section 338 has remained essentially dormant since enactment — no President has formally invoked it. It overlaps significantly with Section 301 of the Trade Act of 1974, which has supplanted it in practice because Section 301 has a more developed procedural framework and broader remedies.
The authority has been raised as a potential alternative or supplement when other tariff authorities — particularly IEEPA — face legal challenges. Unlike IEEPA, Section 338 doesn't require a declared national emergency, but the 50% statutory cap limits how aggressive it can be.
Section 338 is one of several "sleeping giant" tariff authorities (along with Section 122) that the executive branch retains independent of subsequent trade statutes.