The importer must demonstrate that the articles are of US origin and were not advanced in value or improved in condition while abroad. Supporting documents typically include the original export records (such as a Shipper's Export Declaration or AES filing), a declaration from the foreign recipient confirming no processing occurred, and any relevant commercial invoices. CBP may request additional evidence for high-value or complex goods.

Under subheading 980110, duty applies only to the value of the repairs or alterations performed abroad — not to the full value of the article. The article itself must have been previously imported and dutiable, and the work performed must constitute a repair or alteration rather than a manufacturing operation that creates a new article. If the foreign work transforms the article into something substantially different, the full value of the returned article may be dutiable.