When it comes to the race to develop autonomous vehicles, Google and its fellow tech companies have gotten a lot of publicity. But the tech giants may have a tough time beating out the traditional car makers and parts suppliers, if a new study is any indication.

To get a sense of which companies are leading the development of autonomous car technologies, The Cologne Institute for Economic Research identified and analyzed 5,839 related patents from the past seven years. As we can see in this chart from Statista, which is based on The Cologne Institute's data, traditional automakers and parts suppliers — led by a trio of German companies — are leaving Google and the rest of the tech industry in the dust.

Far in front is Bosch, a longtime parts and systems supplier for the auto industry. That may seem surprising, but Bosch has been increasingly focusing on autonomous car technologies. It's even been working with some of its nominal rivals, developing the steering system for Google's prototype self-driving car and supplying driver assistance systems — things like automatic braking systems that are the precursors to self-driving cars — to Tesla.