The FCC's investigation into network monopoly practices that began in 1938 was completed with a Report on Chain Broadcasting. This report aimed to protect individual affiliate stations from what the FCC felt was undue control by the networks. Among other things, it limited affiliate contracts to one-year renewable periods, permitted stations to use programs from other networks, prevented networks from interfering with station programming and scheduling prerogatives and stopped networks from controlling affiliate stations' advertising rates for other than that network's programs. However, the report's most dramatic determination was that NBC's ownership of two networks constituted an unacceptable monopoly (Hilliard & Keith, 2012).