Uber has devised a “clever and sophisticated” scheme in which it manipulates navigation data used to determine “upfront” rider fare prices while secretly short-changing the driver, according to a proposed class-action lawsuit against the ride-hailing app.

When a rider uses Uber’s app to hail a ride, the fare the app immediately shows to the passenger is based on a slower and longer route compared to the one displayed to the driver. The software displays a quicker, shorter route for the driver. But the rider pays the higher fee, and the driver’s commission is paid from the cheaper, faster route, according to the lawsuit.

“Specifically, the Uber Defendants deliberately manipulated the navigation data used in determining the fare amount paid by its users and the amount reported and paid to its drivers,” according to the suit filed in federal court in Los Angeles. Lawyers representing a Los Angeles driver for Uber, Sophano Van, said the programming was “shocking, “methodical,” and “extensive.”