An Uber customer filed a proposed class action lawsuit against the company earlier this year, saying an advertised 20 percent gratuity is "false, misleading, and likely to deceive members of the public" because Uber keeps a substantial portion of the money.
Uber's business practices have come under scrutiny, with some customers alleging privacy violations. Earlier this month a senior Uber executive caused an uproar when he told journalists that Uber should consider hiring researchers to examine and disclose activities of media critics.
Kalanick apologized for the executive's comments and the company hired an outside law firm to review its privacy policies.
In the driver gratuity lawsuit, plaintiff attorneys argued that Kalanick and other executives should disclose emails that contain evidence about Uber's tipping practices.
The company said that would be overly burdensome because such policies are set by the general manager in each city, which operate as their own "individual business," according to a court filing.
At a hearing on Wednesday in an Oakland, California federal court, U.S. Magistrate Judge Donna Ryu said Uber is a new startup with relatively few employees.
Driver gratuities is an issue that Kalanick and other top executives "are likely to be involved in," Ryu said.
The case is Caren Ehret vs. Uber Technologies Inc in U.S. District Court, Northern District of California, No. 14-0113.
© Thomson Reuters 2014