Following a legal battle that lasted 11 years, American Airlines Group wants to force defendant Sabre Corp to pay its legal fees. 

U.S. law firm O’Melveny & Myers filed a lawsuit on behalf of American Airlines on Friday, saying the Texas-based global distribution system should pay American’s fees.

Those fees could amount to at least tens of millions of dollars. The 11-year litigation included two trials and an appeal. The filing did not identify an amount, but a O’Melveny partner previously said in court that the fees were “very, very substantial.”

American Airlines was awarded $1 in May as the winner of an antitrust trial against Sabre.

The dispute was over practices Sabre used to force airlines to use its services, and prevent carriers from reaching out to travel agents and business travelers more directly. American inherited the case when it acquired US Airways in 2013. US Airways had sued Sabre in 2011.

The result in May found that Sabre’s practices did not cause American Airlines any financial harm.

Friday’s filing shows that the two companies tried to resolve the fee dispute without involving the court but did not reach an agreement.

Tags: airlines, american airlines, global distribution systems, lawsuits, news blog, sabre, travel tech