The Uyghur Forced Labor Prevention Act (UFLPA) creates a rebuttable presumption that goods produced wholly or in part in the Xinjiang region of China — including cotton and cotton-containing products — are made with forced labor and are inadmissible. Importers of cotton fibers and yarns must be prepared to provide detailed supply chain documentation tracing fiber origin to rebut this presumption if CBP initiates a detention.

Filament yarns are made from continuous synthetic or artificial strands extruded in long lengths, while spun yarns are made by twisting together short staple fibers (natural or cut synthetic). The distinction places them in different HTS chapters — filament yarns generally in Chapters 54 or 55, spun yarns in Chapter 52 (cotton) or 55 (synthetic staple) — with different duty rates and trade-remedy applicability.