This is all supposition, but I'm willing to bet that if such a position is available at Google, it would be necessary to have at least a Master's and preferably

This is all supposition, but I'm willing to bet that if such a position is available at Google, it would be necessary to have at least a Master's and preferably a Ph.D., with an emphasis on AI, in order to get such a position. The beauty of startups is that you can start them whenever you have the time and inspiration, and the artificial degree barrier is non-existent if your product is good enough.