The price is less than what JPMorgan Chase's One Equity Partners paid for a similar stake four years ago and brings CBS Corp. into an equal partnership with Lions Gate Entertainment Corp.
The deal terms come from a person who wasn't authorized to speak publicly and spoke on condition of anonymity.
CBS says the channel, available in more than 80 million homes, will continue to focus on entertainment. Details about rebranding it will come. It will combine CBS' programming, production and marketing with Lions Gate's resources in movies, TV shows and digital content.
TV Guide magazine isn't part of the deal.