WordPress cofounder Matt Mullenweg and his company Automattic have asked a court to dismiss WP Engine’s lawsuit accusing them of libel and extortion. In a filing on Wednesday, Mullenweg argues that WP Engine is conjuring claims “out of legal thin air,” while alleging it continues to use the WordPress trademark “in unauthorized ways.”

Earlier this month, the third-party WordPress hosting service WP Engine filed a lawsuit against Automattic and Mullenweg after the executive embarked on a “scorched earth nuclear” campaign against it. In addition to accusing WP Engine of trademark infringement, Mullenweg claimed the service doesn’t contribute enough to the open-source WordPress.org project, which Mullenweg also controls. WordPress.org also cut off WP Engine’s access to its resources and later took over one of its most popular plugins.

As noted in the filing, Mullenweg claims he has “no obligation to provide” WordPress.org’s resources to WP Engine. “The mere fact that WP Engine made the risky decision to base its growing business on a site to which it has no rights or guarantee of access, without making backup plans, is not enough for it to conjure a claim out of legal thin air,” the filing reads.

Mullenweg goes on to claim WP Engine has “chosen without justification to attack Automattic and Matt,” despite allegedly having “no legal (or moral) rights” to WordPress.org’s free services.

This very public spat has raised concerns among developers across the WordPress ecosystem who now worry whether they, too, could get cut off from WordPress. But Mullenweg doesn’t seem too worried about the impact. During an interview at TechCrunch’s Disrupt event on Wednesday, Mullenweg said his fight against WP Engine is “obviously” worth the risk.

A hearing for WP Engine’s case against WordPress is currently scheduled for next March.