During the trial, which was conducted remotely via Zoom, Ironburg says that it had warned Valve about one of its alleged patents as far back as 2014. To be precise, the patent infringement relates to the buttons built into the back of the controller, which can easily be operated with a user’s middle fingers.
Valve’s defense to Ironburg’s accusation was, surprisingly, simple, stating that the rear-mounted buttons on the Steam Controller did not match the outlines of Ironburg’s patents. That, including a statement that the plaintiff’s accusation was a decision “based on altered reality”.
Despite its warnings, Valve simply ignored Ironburg and went ahead with the production of its Steam controller with said rear buttons; it managed to sell approximately 1.6 million units before being discontinued back in 2019. At the time of writing, the trial is still ongoing. (Source: Law360, GameIndustry, VGC)