The Korean professional Kim MyungWan, 8p lost a handicap 9
game against MoGo.
Citation:
"For the very first time in history, and after 40 years of research,
a program defeated a professional Go player in a 9 stones handicap
game. (...)
The match involved the collaboration
between French researchers, who developed most of the software, and
Dutch researchers, who provided the cutting-edge Supercomputer Huygens
and contributed to the code. 'MoGo played really well,' said Kim,
who estimated its current strength at '2 or maybe 3 dan,'
though he noted that the program — which had a processing power more
than 1000 times higher than the chess program Deep Blue — 'made some
5-dan moves.'"