Inventor-controlled InfoGation Corporation has sued Alphabet (Google) (6:20-cv-00366) over the provision of the Google Maps API, targeting features related to route optimization and natural language route description. The case follows two previous suits filed against each of HTC, Huawei, and ZTE over their provision of Android smartphones equipped with Google Maps, as well as a 2016 declaratory judgment action filed by Google against InfoGation. The asserted patent in the new case has been at issue throughout the litigation; it generally relates to producing navigation guidance from turn-by-turn directions generated from natural language output.