Taxi disruptor refused to share business information.
Taxi app Uber has been fined $7.3 million for hiding information from California Regulators.
On Wednesday, the California Public Utilities Commission (CPUC) ordered the company to pay the amount within 30 days or it faces losing its license to operate in the state.
The decision was issued by chief administrative law judge Karen V. Clopton. The CPUC said Ubber had failed to make available the necessary information to operate in California.
Some of the unshared files include reports on causes of accidents, drivers turning down journey requests and the amount of disabled access cars available.
Eva Behrend, Uber’s spokeswoman said: "This ruling – and the associated fine – are deeply disappointing.
"We will appeal the decision as Uber has already provided substantial amounts of data to the California Public Utilities Commission, information we have provided elsewhere with no complaints.
"Going further risks compromising the privacy of individual riders as well as driver-partners. These CPUC requests are also beyond the remit of the Commission and will not improve public safety."