With 73 cars and 230 approved human drivers in the state, Google has by far the most vehicles and people focused on test-driving its technology on public roads. (Plus, Google has additional vehicles in Texas and Washington.) That’s nearly as many as the 77 cars with permits from the other 10 companies combined. Google also has 70 more human drivers permitted to do test driving than its rivals have altogether. Tesla comes in second for the most cars with test-driving permits. As of March 1, it had eight registered vehicles and five permitted drivers.

Here’s how the numbers break down:

There are, of course, limitations to assessing the strength of any one company based solely on these numbers. Technological history has proved repeatedly that the factors that make one company’s model win out over another’s have to do with a soup of technological, economic, and social factors. Being first isn’t everything. And even being the best doesn’t guarantee success.

Plus, there are a few glaring omissions on the list above: Apple and Uber are both believed to be working on their own driverless-car strategies, though neither company has provided much, if any, detail on what they’re building. At times it seems they haven’t been sure themselves. Last year, the Uber CEO, Travis Kalanick, said his company wouldn’t manufacture its own cars, but definitely wants its fleet to be self-driving eventually. More recently, the Uber’s chief product officer hinted that it would consider manufacturing its own vehicles after all.

Apple’s plans remain mysterious even to those who have worked on self-driving cars for years. “There is a joke in the Bay Area that if you know somebody in the vehicle space and they left their old job but they haven’t updated their LinkedIn, they must be at Apple,” Chris Gerdes, a professor of mechanical engineering at Stanford University, told me last fall. And in a chapter of this saga that seems straight out of Willy Wonka, residents in Sunnyvale, California, have complained of middle-of-the-night “loud motor noises” roaring out of a former Pepsi bottling plant leased by Apple.

Amid all the secrecy, public records in California help put a spotlight on the testing that’s being done publicly. That work is meaningful and revealing. Any company that wants to be a leader in the design and manufacture of self-driving vehicles will eventually have to put their cars and trucks on real roadways. For now, in California at least, Google is dominating them.

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