There appears to be five patents that currently protect Google's driverless car.
The only patent granted so far is entitled Transitioning a mixed-mode vehicle to autonomous mode, which we reported on shortly after it was published by the USPTO last December.
Four more patents are currently pending:
What makes this set of patents especially interesting is their credited inventors. With the exception of patent number four (4), Christopher Urmson is part of the remaining four patents. In patent one (1), Urmson is credited together with Sebastian Thrun, vice president and fellow at Google, and possible Google's best known scientist at Google X and the public face of Google's driverless car system. Thrun headed Stanford University's self-driving car effort which won the DARPA Grand Challenge with the "Stanley" car in 2005 and placed second in 2007 with "Junior". Thrun was a professor of computer science and electrical engineering at Stanford between 2007 and 2011 and joined Google in April 2011 full time.
Urmson was also a major contender in the DARPA Grand Challenge and was the technology lead at Carnegie Mellon University's Tartan Racing team, which won the 2007 Grand Challenge and its $2 million prize. Their vehicle "Boss", a modified Chevrolet Tahoe SUV, covered a 60 mile road course in 4 hours and 10 minutes, ahead of Stanford's Junior, which arrived after 4 hours and 29 minutes. Only six teams finished the event. Virgina Tech was third, MIT fourth, a team consisting of University of Pennsylvania and Lehigh University fifth and Cornell University sixth.
With Urmson and Thrun, Google has the most experienced individuals on its staff to develop a self-driving car. Along with Urmson, Google appears to have hired the Who's Who of DARPA Grand Challenge contenders, including Nathaniel Fairfield, Philip Nemec, Michael Montemerlo, Dmitri Dolgov, and David Ferguson.