WASHINGTON — The fierce battle between the National Assn. of Broadcasters and EchoStar has landed at the Supreme Court over the issue of whether satcasters must provide all local signals or none.

In papers filed with the high court late Monday, the NAB asked the robes to reject EchoStar’s claim that the none-or-all carriage rule is unfair and a violation of the First Amendment.

The law EchoStar is challenging went into effect Jan. 1 and mandates that a satcaster offer customers all local broadcast signals or none.

In its Supreme Court filing, the NAB said the law is designed to protect satcasters from bestowing any one TV station in a particular market with an unfair competitive advantage, among other things.

Joining the NAB in the filing were Univision Television, the Assn. of Public Television Stations, the Corp. for Public Broadcasting and PBS.

EchoStar appealed to the Supreme Court earlier this year after losing an appellate court ruling.

EchoStar topper Charlie Ergen has insisted that his Supreme Court fight does not undermine his promise to offer local signals in all markets should the proposed EchoStar/DirecTV merger be approved in Washington. Rather, Ergen said he is fighting the new law on principle.