Apple is set to test autonomous vehicles after securing a permit in California. Self-driving car technology is being developed in a crowded arena of companies that Apple appears keen to keep abreast of.

The permit allows it to conduct test drives in three vehicles with six drivers, according to California state officials. The cars in question are all 2015 Lexus RX450h.

Apple has not announced it is building an electric car but has recruited dozens of automotive experts in recent years – obtaining testing permits will fuel speculation that it plans to.

“This does confirm what’s long been rumoured – that Apple is at least toying with the idea of getting into the autonomous game in some capacity,” said independent consultant Chris Theodore, a former vice president at Ford and Chrysler.

The permit does not mean Apple is definitely building a car, he added. “This is not necessarily automobiles as initially rumoured, but software or possibly hardware associated with autonomous technology.”

An Apple spokesman declined to comment, pointing to a statement the company made in November on the subject of regulating self-driving vehicles.

“Apple is investing heavily in the study of machine learning and automation, and is excited about the potential of automated systems in many areas, including transportation,” the company’s director of product integrity, Steve Kenner, wrote in that five-page letter to the US National Highway Traffic Safety Administration.

.Apple executives have been coy about their interest in cars. Chief executive Tim Cook has suggested that Apple wants to move beyond integration of Apple smartphones into vehicle infotainment systems.

Apple joins a growing list of traditional carmakers, technology companies, and small start-ups to test-drive cars in California – all vying to be the first to have commercially viable vehicles on the roads.

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Companies that have been issued similar permits include Alphabet, Ford, Volkswagen, Daimler, Tesla and General Motors.

Some expect to launch driverless cars by 2020 but experts believe it may take much longer due to regulatory challenges.