Fair Debt Collection Practices Act (FDCPA): Federal law that restricts debt collection practices and provides guidelines for debt collectors' behavior, communication methods, and consumer rights.

Fair Credit Reporting Act (FCRA): Federal law governing the collection, dissemination, and use of consumer credit information, including requirements for reporting debt sales and transfers.

Consumer Financial Protection Bureau (CFPB) Regulations: Federal regulatory framework that oversees consumer financial products and services, including debt sales and collection practices.

Truth in Lending Act (TILA): Federal law requiring disclosure of credit terms and standardizing the manner in which costs associated with borrowing are calculated and disclosed.

Dodd-Frank Wall Street Reform: Comprehensive federal law that reformed various aspects of the financial industry, including consumer protection and debt collection practices.

Gramm-Leach-Bliley Act: Federal law requiring financial institutions to explain their information-sharing practices and protect sensitive data, crucial for debt sales involving consumer information.

State Debt Collection Laws: State-specific regulations that may impose additional requirements beyond federal laws for debt collection and sales within particular states.

State Usury Laws: State-specific regulations governing maximum interest rates and related charges that can be applied to debts.

State Licensing Requirements: State-specific rules requiring debt buyers to obtain proper licensing or registration before purchasing or collecting debts.

UCC Article 9: Uniform Commercial Code article governing secured transactions, including the sale of payment rights and security interests in financial assets.

UCC Article 3: Uniform Commercial Code article governing negotiable instruments, relevant for the transfer of promissory notes and other debt instruments.

UCC Article 2: Uniform Commercial Code article governing sales, which may apply to certain aspects of debt sales transactions.

OCC Guidelines: Office of the Comptroller of the Currency regulations governing national banks' debt sales practices and requirements.

Federal Reserve Board Regulations: Federal Reserve guidelines affecting banking institutions' debt sales practices and compliance requirements.

FDIC Regulations: Federal Deposit Insurance Corporation rules governing insured institutions' debt sales practices and safety and soundness requirements.

State Privacy Laws: State-specific regulations governing the protection and handling of consumer private information during debt sales transactions.

Data Security Regulations: Federal and state requirements for securing and protecting consumer data during debt sales and transfers.