It’s likely a similar story to Mitsui, where it’s actually just a huge family and people use their name to increase trust. EDIT: turns out both companies came

It’s likely a similar story to Mitsui, where it’s actually just a huge family and people use their name to increase trust. EDIT: turns out both companies came to this logo independently. The pen company got to it first, and the Mitsubishi Group and the pen company decided to allow mutual usage due to non-competing business areas. https://ja.wikipedia.org/wiki/%E3%82%B9%E3%83%AA%E3%83%BC%E3%83%80%E3%82%A4%E3%83%A4 https://ja.wikipedia.org/wiki/%E3%82%B9%E3%83%AA%E3%83%BC%E3... ^ here’s some more info for Japanese speakers. Basically both companies derived their logo from various family crests and it’s a pretty common shape so it ended up like this