The U.S. Supreme Court cited the Restatement of the Law Third, Property: Mortgages, in holding that a business that engaged in no more than the enforcement of a security interest—such as a law firm that pursued nonjudicial foreclosures on behalf of clients—was not a “debt collector” within the meaning of the Fair Debt Collection Practices Act, 15 U.S.C. § 1692a(6), except for the limited purpose of § 1692f, which prohibited entities from threatening to foreclose on a consumer’s home without having legal entitlement to do so.