Author Clive Cussler has been ordered to pay $5m (£2.5m) to the company which made his book Sahara into a flop movie.
Clive Cussler has written 19 Dirk Pitt adventures
Mr Cussler and Crusader Entertainment have been engaged in a legal battle since the 2005 film was in production.
A Los Angeles jury decided he acted in bad faith by slating the film, arguing over the script and inflating his book sales when dealing with the company.
But the jury left the judge to decide whether Crusader owed Mr Cussler $8m (£4m) for the rights to a second book.
Both sides left claiming victory and Mr Cussler told reporters he was "relieved it's over".
Mr Cussler originally claimed $40m (£20m) from Crusader in 2004, alleging the company reneged on a contract that gave him approval rights over the film's screenplay.
Crusader countersued for $110m (£55m), accusing the author of exaggerating his book sales to get the movie made.
It also said Mr Cussler clashed with screenwriters brought in to polish Sahara's script, tried to get producers to accept his own screenplay version and criticised the film before its release.
The film, starring Matthew McConaughey as adventurer Dirk Pitt, opened well but took only $119m (£60m) at the global box office, against a cost of $130m (£65m).
Jurors heard 14 weeks of evidence and deliberated for eight days before deciding Mr Cussler had breached an "implied covenant of good faith".