Patent trolls are on the loose again.
Patent trolls are common in the technology industry and it seems like "Terminal Reality and Infernal Technologies" is targeting Microsoft this time. You might remember the name from a complaint involving EA from 2015. While that case was settled around October 2017, it seems like the company has a new target. Developer Terminal Reality closed in 2013, and since then it seems like its affiliate Infernal Technologies has been suing game developers.