The US Supreme Court in American Broadcasting Cos., Inc. v. Aereo, Inc. held that Aero’s retransmission of broadcast television signals qualified as a public performance of a copyrighted work under the Copyright Act of 1976.  The US Supreme Court found that Aereo’s activities were substantially similar to the activities of community television providers that led Congress to amend the Copyright Act.  The US Supreme Court opinion can be found here ABC v Areo