American Airlines is suing Gogo, saying that the in-flight Wi-Fi provider must either improve its internet speeds or end its contract with the airline.

According to a regulatory filing from Gogo, as spotted by BuzzFeed News, American claims it has found an alternative service provider, ViaSat, offering better service. Under the contract, Gogo must create a new, competing proposal or allow American to terminate the contract, which Gogo says represents about 200 planes.

Gogo released the regulatory filing today, as the company's stock price fell drastically on news of the lawsuit, first reported by the Fort Worth Star-Telegram. Calling American "a valued customer," the company said it was "look[ing] forward to resolving the disagreement regarding contract interpretation that led to this declaratory judgment action."

The company added that it was planning to offer a new proposal through its "2Ku" satellite service. "We believe that 2Ku is the best performing technology in the market and look forward to discussing our offer with American," Gogo said in the statement.