Does the US depend on three private companies for its voting equipment?

More than 90% of U.S. voters use systems developed by one of three privately-owned companies, according to a 2016 Wharton School report. Wharton estimates their total revenue to be about $300 million. The vendors receive little federal oversight aside from voluntary testing of functional requirements, relatively relaxed oversight compared with what the government gives, say, military equipment, a report by the Brennan Center for Justice notes.

One of the three, Dominion Voting, publicly denied a range of false claims about its performance in the Nov. 3 elections, including allegations of ties to prominent Democratic leaders or donors. The company, founded in Canada and now based in Colorado, noted that post-election scrutiny in Arizona, Michigan and Georgia (where the state reviewed every vote) has confirmed the security of its systems and the accuracy of its tabulations.