Probably for support / sales / community outreach based stuff. Lots of people in Japan, even techies, have less than stellar English skills. There are also a l

Probably for support / sales / community outreach based stuff. Lots of people in Japan, even techies, have less than stellar English skills. There are also a lot of companies here that are still in the dark-ages when it comes to technology (e.g. I worked at a company that tried CVS in 2009 before I joined but didn't see the point of version control) Sales / Support staff fluent in Japanese will help a lot I think. Japan has 130 million people. I think there is probably lots of room for Expansion for github. Having a Japanese sub also makes taking payments easier, I am sure there are other legal / administrative reasons.