SAN FRANCISCO — Ruling in a case with implications for the entire on-demand economy, a federal judge on Tuesday certified a class of Uber Technologies Inc. drivers seeking employee status and reimbursement for withheld tips.

U.S. District Judge Edward Chen of the Northern District of California found the drivers’ situations are similar enough that the threshold question—whether drivers are employees or independent contractors—can be answered on a classwide basis. He certified a class of California drivers who have worked for Uber since 2009, and will allow the class to proceed with claims that Uber illegally kept drivers’ tips.