Fujitsu
Fujitsu a Japanese multinational computer hardware and IT services company headquartered in Tokyo. (Japan)
Fujitsu sponsors the the (International Go Federation) Fujitsu Cup
In 1992 Fujitsu published Ikeda Toshio's On the Rules of Go (this is also known as the Ikeda rules)
On Sensei's library I also found the Fujitsu Under 15 cup page I don't know if they have any relation with it.