NEW YORK (AP) — The country’s biggest TV networks — ABC, CBS, NBC and FOX — are suing Locast, a streaming service that transmits their broadcasts for free.

The companies say that Locast is violating their copyrights. Locast has held that under the law, it is
allowed to stream
the networks without paying them because it is a non-profit.

The lawsuit comes after Locast
last month
got a $500,000 donation from AT&T. AT&T has integrated Locast into its DirecTV and U-verse cable services, as has Dish. That could help the TV providers in its fights with the networks over money that sometimes leads to blacked-out channels. AT&T also is in a payment dispute with CBS that has taken CBS off its platforms.

Locast did not immediately respond to a request for comment.