California handed out its first 29 permits this week to three companies to test self-driving vehicles on public roads.
Google got permits for testing 25 modified Toyota Motor Corp Lexus SUVs. Daimler AG's Mercedes-Benz and Volkswagen AG's Audi received permits as well, said Bernard Soriano of the California Department of Motor Vehicles, according to Reuters.
Audi, Lexus, and Mercedes-Benz are all luxury brand vehicles.
Soriano added that Audi was the first to apply for the permits. All permits were issued on Sept. 16, the first day they were required by California, which has the largest population of any state in the U.S.
Other automaker and first-tier automotive suppliers are currently filing for the permits, Soriano said.
Self-driving car testing has been underway in California for a number of years already without the permits, but the state's legislature has made permits a requirement for them to run on public roads.
Requirements to get a permit includes the ability of test drivers to be able to take command of an autonomous vehicle at any time.
Mercedes-Benz engineers will "teach" self-driving vehicles how to operate safely on U.S. roads by using different methods than are used in the development and testing of the cars in Germany, to officials at Daimler and Mercedes-Benz.
Audi was also the first automaker to obtain a license for an autonomous vehicle in Nevada, back in 2012.
Daimler and Volkswagen are both based in Germany, and Google is based in Silicon Valley, CA.
The state hasn't allowed operation of self-driving vehicles by members of the public, but a state law requires rules governing how companies have to certify such vehicles to be ready by the end of 2014.
Manufacturers have to carry a $5 million insurance policy or surety bond and must report any accidents involving the autonomous test vehicle to the state DMV. Companies also have to report any situation in which the vehicle's autonomous functions stop working during a test drive.
Nissan has previously said it expects to sell autonomous vehicles by 2020 if the market is ready. Toyota and Cadillac both have promised to launch a number of models with vehicle-to-vehicle communications technology starting in 2017.
Audi has been at the forefront of research "taking automated driving from science fiction to pre-production readiness" and obtaining the first California permit "shows that we intend to remain the leader in this vital technology frontier," Scott Keogh, president of Audi of America, said in a statement released Tuesday.