Volkswagen AG is facing one of the largest-ever U.K. class action lawsuits, with almost 100,000 vehicle owners accusing it of misleading them by installing emissions-cheating software that made it appear their diesel vehicles met environmental standards.

Lawyers for the drivers opened their case Monday, and must first prove that the allegations belong in court. They need judges to follow findings by regulators that led to vehicle recalls, and to rule that the software is a so-called defeat device that's banned under European law. Then the case would proceed to another trial to decide whether the owners lost anything from buying the vehicles.

The automaker has faced numerous lawsuits after the use of the software designed to lower emissions when being tested was exposed by a U.S. probe in 2015. That led to a recall throughout Europe that cost the company €29 billion ($32 billion).