Satoshi Nakamoto gradually left the Bitcoin project during 2010.
His last known communication with the Bitcoin community was in December 2010 when he expressed concerns about the project's direction, and handed over control of the Bitcoin source code repository to Gavin Andresen, while his last significant contribution and communication occurred in December 2010.
Gavin Andresen, April 27, 2011, 07:00:26 PM:
"I'm going to give a presentation about Bitcoin at CIA headquarters in June at an emerging technologies conference for the US intelligence community."