Apple is increasingly taking its automated vehicles for a test drive — despite remaining tight-lipped about its ambitions.

Between December 2022 and November 2023, the tech giant’s autonomous fleet, which boasts 67 vehicles, logged 450,000 miles, more than triple over the year before, for the largest spike among companies with the most testing in the state, The Washington Post reported.

^{Image Credit: picture alliance | Getty Images. Self-driving test car from Apple.}

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Apple has a reputation for keeping its product development quiet, leading some experts to call the experimentation with its automated technology under the public’s and regulators’ watch “a vote of confidence in the potential of automated driving,” per the outlet.

Google-owned Waymo racked up more than 4.8 million miles last year, and General Motors-owned Cruise snagged the second-highest mileage at 2.7 million, according to state Department of Motor Vehicles data.

California state regulators gave both Waymo and Cruise permission to operate 24/7 robotaxi services in San Francisco last summer, but the California Department of Motor Vehicles suspended Cruise’s permit just months later following allegations that the company withheld video footage from an incident that left a pedestrian stuck beneath its robotaxi, TechCrunch reported.

Related: What Happens When Self-Driving Cars Crash? The Legal Ramifications of Automation

Apple has been developing autonomous vehicles for years but only has permits to test in California with a human driver, per The Post.

In January, Bloomberg reported that Apple had delayed the launch of its self-driving technology to 2028 and is working on an electric vehicle “with more limited features.”

Apple Inc is up nearly 25% year over year.