These subscribers also circumvent the procedures for telemarketing followed by registered telemarketers. These generally include types of unsolicited calls from telemarketers and robocalls. However, some telemarketers block or fraudulently spoof caller ID to prevent being traced. In the United States, telemarketers are required to transmit caller ID. The FTC responded by clarifying that cell phones cannot legally be called by telemarketers. Telemarketers were used to make phone calls with scripted dialogues to promote Harding. In the early 21st century, brokers and telemarketers actively pushed subprime mortgages. Telemarketers and call centre employees are thought to be most at risk. It soon became an indispensable system allowing customers to screen calls from telemarketers. Some attempts have been made by telemarketers to skirt the do-not-call list rules. Ray has a penchant for prank calls, whether outgoing (Marmaduke, Cathy) or incoming (telemarketers). This type of instrument is usually used by credit card companies, utility companies, or telemarketers. Business professionals, physicians, professors, researchers, telemarketers, etc. In July 2001, Florentine released "Terrorizing Telemarketers Volume 1". Lenny is a chatbot designed to waste time of telemarketers.