Facebook is preventing content from websites that post digital blueprints for 3D-printed guns from being shared on its online platform amid a legal fight over whether one open-source organization can publish the controversial plans.

“Sharing instructions on how to print firearms using 3D printers is not allowed under our Community Standards,” a Facebook spokesperson told the Washington Examiner, after the ban was first reported by BuzzFeed News. “In line with our policies, we are removing this content from Facebook.”