On Friday Uber posted a notice saying that the company had discovered that one of its databases had a point of entry for unauthorized users. On further investigation it found that “a one-time unauthorized access to an Uber database by a third party had occurred on May 13, 2014.” That database reportedly contained driver names and license numbers.

“Our investigation determined the unauthorized access impacted approximately 50,000 drivers across multiple states, which is a small percentage of current and former Uber driver partners,” the note by Katherine Tassi, Uber’s Managing Counsel of Data Privacy, stated. The company added that it has not received any reports of identity misuse, although it's unclear whether divers have reported anything since learning about the breach.

Uber said it was alerting affected drivers and will offer them a free one-year membership to an identity-monitoring service. Tassi said that Uber had filed a “John Doe” lawsuit in order to “gather information that may lead to confirmation of the identity of the third party.”

Uber has had privacy issues in the past—not so much at the hands of hackers, but at the hands of its own management. Last year, the CEO of Uber suggested that the company do “opposition research” into the comings and goings of journalists who wrote negative things about Uber. Before that, the company was flung into scandal when it displayed the real-time activity of 30 of its “notable users” at a launch party in Chicago.

Correction: This post originally stated that license plate numbers had been stolen from Uber's database. However, drivers license numbers were actually stolen. Ars regrets the error.