AT&T, the owner of DirecTV, is backing a free streaming service as a hedge against losing broadcast channels in disputes over fees.

TV subscribers are increasingly finding the channels they pay for blacked out because channel owners and the cable or satellite companies such as DirecTV can't agree on fees. Such fights can drag on for months and block viewers from the Oscars, the Super Bowl and other events.

AT&T said Thursday that it donated $500,000 to Locast, a non-profit organization that streams broadcast channels for free. It's also offering access to Locast through DirecTV and its U-verse cable service.

This option could undercut threats by the station owners to pull channels during disputes. Customers missing channels like ABC, CBS, NBC and Fox could also use a digital antenna. Neither Locast nor an antenna would help if the blacked-out channel is a cable network like Comedy Central or ESPN.

The donation is a pittance for AT&T, with $19.4 billion in profit last year. But it's significant for Locast , which depends on donations and spends about $100,000 to launch each new market. It's now in 13 cities, including New York, Los Angeles and Chicago.

Cable companies have pushed back against the rising fees demanded by owners of TV stations and cable channels as viewership shifts online. Those fees get passed down to the customer.

AT&T has found itself on both sides of these fights, as it's both a TV provider and a media company as the owner of networks including HBO, TBS and CNN.