Plaintiff/petitioner telemarketers brought these actions challenging the FTC’s and FCC’s joint implementation of a nationwide do-not-call registry. The FTC created the registry as part of its Telemarketing Sales Rule. The Rule prohibits tele- marketers and sellers from calling phone numbers that consumers have listed on the registry. Subsequently, the FCC amended its rules implementing the Telephone Consumer Protection Act (“TCPA”), 47 U.S.C. § 227, to prohibit persons from mak- ing telephone solicitations to residential telephone subscribers who have registered their telephone numbers on the registry. Since June 27, 2003, when the registry opened, consumers have registered more than 50 million phone numbers.