“We are disappointed that StubHub has filed a baseless lawsuit that asks the courts to help prop up its business against true fan-friendly competition,” according to the company. “NBA teams like the Golden State Warriors have implemented ticket exchanges powered by Ticketmaster because they want ticket resale to be a secure experience, not an opportunity for scalping and fraud.”

StubHub’s lawsuit alleges Ticketmaster and the Warriors’ front office cancelled tickets that fans sold on StubHub in a move meant to protect Ticketmaster’s resales business. “StubHub seeks to stop unfair and illegal anti-competitive business practices that prevent fans from deciding how they want to resell their tickets and which artificially drive up ticket prices,” StubHub said in a blog post Monday.

Ticketmaster’s defense continued:

The exchanges are growing in popularity because Ticketmaster and its partners have worked hard to make ticket resale much safer and more transparent, uniquely serving true fans. Ticketmaster does not force any customer to resell tickets on any particular platform and will vigorously defend these specious charges.

This is the latest in a prolonged series of feuds between the two companies. In 2013, Ticketmaster and StubHub also clashed over state ticket resale laws.

Live Nation, which owns Ticketmaster, posted mixed earnings in February. While losses to shareholders doubled to $186.5 million from $82 million, revenue increased 6% to $6.87 billion, Billboard reported.