Shogakukan is a Japanese Tokyo-based publisher of dictionaries, literature, manga, nonfiction, children's DVDs, and other media in Japan. This includes a Sonic the Hedgehog manga series.
Shogakukan founded Shueisha which founded Hakusensha. These are three separate companies, but are together called the Hitosubashi group, one of the biggest publishing groups in Japan.
The company, along with Shueisha, owns Viz Media, which publishes manga from both companies in the United States. Its licensing arm in North America was ShoPro Entertainment; it was merged into Viz Media in 2005. Shogakukan's production arm is Shogakukan Productions Co., Ltd.