HOLLYWOOD (AP) _ The film industry could be faced with an avalanche of lawsuits and the public could see fewer movie classics because of the U.S. Supreme Court's copyright ruling involving the thriller ''Rear Window.''

Entertainment industry attorneys said Tuesday's ruling means film studios re-releasing old movies will have to scour their books to make sure all copyrights are covered.

The court said actor Jimmy Stewart and other owners of ''Rear Window'' must share earnings from movie's 1983 re-release with the current owner of the renewed copyright to the story on which the film was based. The author of the story is no longer alive.

The high court relied heavily on a 1909 law that permits a copyright to be renewed for 28 years after the initial 28-year copyright period ends. The idea is to give authors, other artists and their heirs a second chance to reap rewards from successful works.

''It's going to be potentially an additional cost for the producers and the distributors,'' said Arnold Lutzker, a Washington attorney whose clients include the Directors Guild of America. ''You could find third parties coming out of the woodwork.''

The ruling could cost producers millions of dollars in profits and reduce the financial incentive for making hundreds of film classics available in the United States, said an attorney for MCA Inc.

''It's not all good for the authors,'' said Sheldon Mittleman, MCA's house counsel. Mittleman said motion picture companies may be reluctant to develop movies based on material whose copyrights will soon be up for renewal.

''For the studios and the public, this could be a very serious situation,'' Mittleman said. ''It could mean that the American public will be deprived of the chance to see classic movies.''

The decision is a victory for Sheldon Abend, a literary agent who paid $650 to Chase Manhattan Bank in 1971 for the copyright to the dime-magazine detective story on which ''Rear Window'' was based. The bank administered the author's estate.

Abend said the movie's 1983 re-release infringed on the renewed copyright he bought and that the owners interfered with his plans to contract with Home Box Office cable TV for a new play and TV version of the story.

He said he wants a portion of the more than $12 million the film has earned since 1983 for Stewart, Hitchcock's heirs and MCA Artists Ltd.

The ruling also could affect the recording industry, live theater and computer software, said Stephen Kroft, a lawyer who filed a brief on behalf of several major film companies opposing Abend's claim.

''It's a noose around the neck for owners of these works,'' Kroft said. ''It's very unfortunate. It's got potentially very broad ramifications.

''And a work can incorporate or be based on all kinds of different copyrighted work - songs, especially. Think about a film like 'American Graffiti' and all the songs in it,'' Kroft said.

Stewart was traveling but spokesman John Strauss said the actor would not discuss legal matters.

''Rear Window,'' which starred Stewart and Grace Kelly, is based on ''It Had to be Murder,'' a short story by Cornell Woolrich first published in 1942 in Dime Detective Magazine.