SAN FRANCISCO (AP) - A federal judge granted class-action status Tuesday to a case in California against Uber over the payment of its drivers.

SAN FRANCISCO (AP) A federal judge granted class-action status Tuesday to a case in California against Uber over the payment of its drivers.

The ruling increases the number of potential California plaintiffs in the lawsuit claiming Uber drivers are incorrectly classified as independent contractors when they are actually employees.

U.S. District Court Judge Edward Chen in San Francisco made his decision in the lawsuit filed by four current or former drivers for the ride-hailing company.

It raises the stakes for Uber, which could be on the hook for significantly more damages if it loses the case.

The drivers named in the lawsuit say they are Uber employees and have been shortchanged on expenses and tips.

Their lawsuit sought class certification on behalf of 160,000 drivers who have worked for the company in California since 2009. Chen certified the class, though he exempted some drivers and limited it to the drivers' claims for tips, not expenses.

A call to Uber was not immediately returned.

In his ruling, Chen rejected Uber's arguments that the named plaintiffs in the suit were not typical of their fellow class members because there is no typical Uber driver. Uber also argued that other Uber drivers, unlike the named plaintiffs, preferred being independent contractors instead of employees.

Chen said the company had shown little evidence for that claim.

"Should the jury determine that the class members here are not Uber's employees, this class action will have reached its end," the judge wrote. "Should the jury determine they are Uber's employees ... they are likely to be entitled to relief as a class at least with respect to the California tips law."