Although an April 23, 2011 email is the last proven message sent by Satoshi Nakamoto, numerous communications have been publicized since that have not been disproved. Such examples, if genuine, rule out Len Sassaman (died July 3, 2011) and Hal Finney (died August 28, 2014) once and for all while also putting serious doubt on numerous other candidates for Satoshi.
Let’s examine some:
March 7, 2014: Satoshi wrote “I am not Dorian Nakamoto” on the P2P Foundation Forum.
September 9, 2014: When Satoshi’s gmx email account was hacked, two people with access to the account did an interview with Vice. The second interviewee, the likely real hacker, claimed that the first interviewee was really Satoshi trying to do damage control.
August 15, 2015: Satoshi emailed the Bitcoin dev mailing list in anger.