16 CFR 701.4 : Commercial Practices (§ 0.1 To Parts 1751-1799) — (§ 0.1 To Parts 902-999) — Federal Trade Commission (§ 0.1 To Parts 902-999) — Rules, Regulations, Statements And Interpretations Under The Magnuson-Moss Warranty Act (§ 700.1 To § 703.8) — Disclosure Of Written Consumer Product Warranty Terms And Conditions (§ 701.1 To § 701.4) — Owner registration cards.

When a warrantor employs any card such as an owner's registration card, a warranty registration card, or the like, and the return of such card is a condition precedent to warranty coverage and performance, the warrantor shall disclose this fact in the warranty. If the return of such card reasonably appears to be a condition precedent to warranty coverage and performance, but is not such a condition, that fact shall be disclosed in the warranty.