Sort of. Google bought DeepMind, the British company which has since turned into a Google team which developed AlphaGo. However, I think the team is still run somewhat independently, at least to the extent that the founders of DeepMind seem to be heading the team. I'm not sure how the rearrangement of Google's holdings into separate holdings owned by the holding company Alphabet worked with DeepMind.
Go America! (But really, at this point, it's more like Team Human vs Team AI—if Lee Sedol loses all 5 games, it'll probably spell the beginning of the end of humans being able to play competitively against computers.