Uber has defended itself following accusations that a lack of internal security allowed employees to spy on rides in real-time.
The firm's former forensic investigator made the allegations in a court declaration.
Uber said it had "hundreds of security and privacy experts working around the clock" to protect its data.
The firm recently settled a case in New York that alleged its "God View" tool was used to monitor rides.
"Uber's lack of security regarding its customer data was resulting in Uber employees being able to track high-profile politicians, celebrities, and even personal acquaintances of Uber employees, including ex-boyfriends/girlfriends, and ex-spouses," wrote former forensic investigator Ward Spangenberg in his court declaration.
Mr Spangenberg was fired from Uber earlier this year and is now suing the company over age discrimination and whistleblower retaliation.
Five former security professionals told news site Reveal and the Center for Investigative Reporting that Uber allowed broad access to ride data.
"Uber continues to increase our security investments and many of these efforts, like our multi-factor authentication checks and bug bounty program, have been widely reported," a spokesman for Uber said in a statement.
"This includes enforcing strict policies and technical controls to limit access to user data to authorised employees solely for purposes of their job responsibilities, and all potential violations are quickly and thoroughly investigated."
The spokesman also denied that "all" or "nearly all" Uber's employees had access to customer data, with or without approval.
"Some teams have never had access to this information," he said.
Staff access to data was logged and routinely audited, the spokesman added.
Uber also said that "God View" no longer existed, and it now had an internal tool called "Heaven View".
In January, Uber paid $20,000 (£13,700) and promised to strengthen privacy policies in order to settle an investigation by New York's attorney general.
It followed a BuzzFeed news story in 2014 that alleged one of its reporter's rides had been tracked via "God View" without her permission.