As it governs debt collection practices, the Fair Debt Collections Practices Act (FDCPA) provides a number of rules that telemarketers who collect debt as third-party debt collectors must follow: 

The Do Not Call (DNC) provisions of the Telemarketing Sales Rule (TSR) are as follows:

Internal Do Not Call List Requirements
The internal DNC list refers to the Entity-Specific Do Not Call Provision. This provision mandates that telemarketers keep and maintain their own do not call list, specific to their organization. When a consumer asks to be put on your do not call list, you should honor that request immediately.