"Keyssa, a wireless technology company backed by iPod creator and Nest founder Tony Fadell, filed a lawsuit against Essential on Monday, alleging that the company stole trade secrets and breached their nondisclosure agreement," reports Gizmodo. Keyssa has proprietary technology that reportedly lets users transfer large files in a matter of seconds by holding two devices side by side. From the report: According to the lawsuit, Keyssa and Essential engaged in conversations in which the wireless tech company "divulged to Essential proprietary technology enabling every facet of Keyssa's wireless connectivity," all of which was protected under a non-disclosure agreement. More specifically, the lawsuit alleges that Keyssa "deployed a team 20 of its top engineers and scientists" to educate Essential on its proprietary tech, sending them "many thousands of confidential emails, hundreds of confidential technical documents, and dozens of confidential presentations." Essential ended this relationship after over 10 months and later told Keyssa that its engineers would use a competing chip in the Essential Phone. But Keyssa is accusing Essential of including techniques in its phone that were gleaned from their relationship, despite their confidentiality agreement. Central to this lawsuit is one of the Essential Phone's key selling points: the option to swap in modular add-ons, made possible thanks to the phone's unique cordless connector. In short, if Keyssa's claims hold water, then one of the phone's defining factors is a product of theft.