Forced Labor Supply Chain Due Diligence: Chain-of-Custody Files for UFLPA Detentions

What does forced labor supply chain due diligence require under the UFLPA?

According to DHS’s Entity List notice of August 2026, since June 21, 2022 CBP has presumed, subject to rebuttal, that goods made by listed entities are made with forced labor and barred under 19 U.S.C. 1307, and the list is not exhaustive. On CBP’s UFLPA FAQ page, last modified in September 2025, the presumption also covers goods with any Xinjiang input, at any tier, even when no listed entity is involved. In this guide's view, a clean Entity List screen therefore does not clear a supply chain; only a trace to where each input was made can show that.

Under CBP’s detention attachment, in its November 2023 edition, the presumption also reaches goods made in or shipped through China and other countries that include Xinjiang inputs, and a detained importer can request an exception or argue that the goods fall outside the law, in writing within 30 days. In the same attachment, an exception needs compliance with the UFLPA Strategy's tracing measures, full answers to CBP's requests and clear and convincing evidence, through every tier including processing in third countries. Which route fits is a question for trade counsel or a licensed customs broker.

According to CBP’s consolidated forced labor guidance for importers, published in June 2026 to supersede its 2022 UFLPA guidance, an importer has 30 days to respond to a UFLPA detention and requests review through the Forced Labor Portal. According to the same guidance, after a denied request the importer may export, destroy or contest the exclusion within 180 days.

In the European Commission’s 2021 forced labour guidance, which is non-binding and written for EU businesses, the OECD due diligence framework appears as six steps. General supplier tiering is covered in the tiered supplier risk assessment method.

Which records does CBP ask for after a UFLPA detention?

In the detention attachment, CBP asks the importer to trace the whole chain from raw materials to the imported goods and to provide a supplier list with addresses, a production flow chart and maps of where each part originated. Under the same attachment, examples include certificates of origin, purchase orders, invoices, proof of payment, bills of lading, production and inventory records and daily manufacturing reports; the list is not exhaustive, and submitting these records does not guarantee release.

In a January 2025 Business Law Today article, Patrick Miller warns that documents a supplier compiles in a hurry carry a high risk of reliability or authenticity problems.

How do you map raw material origins below tier 1?

In the commodity addendum to CBP’s detention attachment, CBP asks for cotton records from the bale level onward with each step numbered, aluminum certificates of origin or affidavits naming where each material is mined, smelted and manufactured, and battery transport records through each production phase. In this guide's view, the same records can support the origin facts that decide trade remedy duty rates.

According to the Commission’s 2021 guidance, where origin is unknown or high-risk, the answer is a plan with suppliers, with deadlines and measurable steps, to verify origin; if that fails and site access is not feasible, suppliers are directed to traders outside the high-risk area. In the same guidance, commodity traders are choke points for deeper checks, and being unable to assess a site in depth is itself a red flag.

Where does isotopic testing fit in supplier verification?

In CBP’s current forced labor guidance, an isotopic test reads a fingerprint that, for cotton, comes from where the plant grew rather than where the seed came from, and compares it with a library of similar materials. In the same guidance, CBP warns that the method is not viable for every product.

In a 2014 peer-reviewed study of unprocessed cotton, cluster analysis of stable isotope data from 17 US and 15 non-US samples placed 15 of the US samples in one group, a promising result from a small sample. In this guide's view, use testing as a sampling check at named points, such as fiber lots arriving at a spinner, and keep the sample custody log beside the report.

Which supplier contract clauses support audits below tier 1?

In the January 2025 article, Miller argues that unilateral representations and warranties put all compliance responsibility on suppliers who often lack the resources to comply, and he describes model clauses that share due diligence duties and reach upstream suppliers. Corrective action over a contract's life is covered in supplier lifecycle governance and corrective action.

In the Commission’s guidance, heightened checks include independent, unannounced access to worksites and workers, and exit terms in corrective action plans stay a last resort, with escalation agreed in advance. According to CBP’s current guidance, supply chain audits should be unannounced and run by independent auditors against the ILO's 11 indicators of forced labor, and CBP generally does not treat financial or environmental audits as sufficient.

According to DHS’s August 2026 notice, listings change by majority vote of the task force's member agencies. In this guide's view, a suspension or termination clause should cover any input made wholly or partly in the Xinjiang Uyghur Autonomous Region or by an entity on the UFLPA Entity List as amended, require disclosure of such an input or a listing anywhere in the chain, and say how open orders, goods in transit and detained goods are handled. Under the model clauses Miller describes, termination for a qualifying breach follows a right to cure, except for zero-tolerance violations.

According to an April 2026 analysis by Debevoise & Plimpton, one of two Chinese State Council regulations issued that month restates existing bans on unlawful supply chain information collection, which the firm reads as likely covering unapproved UFLPA audits. In the same analysis, the firm suggests reviewing audit scope and termination clauses that cite foreign sanctions, while noting that earlier countermeasures were rarely used. In this guide's view, have counsel check the supplier clause above against those rules.

What should a detention response file contain before a shipment is stopped?

On CBP’s FAQ page, recommended practices include a written detention plan, documents ready for immediate submission and protection for trade secrets, since some suppliers may be willing to send records to CBP directly. In the same page, the practices also call for a complete, organized package with English translations, a supplier list showing each role and its documents, and evidence against commingling.

In this guide's view, keep one file per supply chain, numbered by production step, with each original-language record beside its translation, and update it when a supplier, mill or route changes. Sustainability questionnaires belong in this file only when they carry transaction records; designing them is covered in the guide to supplier sustainability data requests.

Which records should a forced labor chain-of-custody file hold?

How do AI agents change forced labor due diligence?