Short answers, pulled from the story.
Coamix was founded on the 4th of June 2000 by Nobuhiko Horie, a former editor-in-chief of Weekly Shonen Jump who serves as CEO, along with manga artists Tsukasa Hojo, Tetsuo Hara, and Ryuji Tsugihara, and voice actor Akira Kamiya.
Coamix is headquartered in Kichijoji, in the Musashino area of Tokyo, Japan.
Coamix published Weekly Comic Bunch from 2001 to 2010. Monthly Comic Zenon was established in 2010 to replace it and remains under Coamix's responsibility.
The Silent Manga Audition is an open competition for Japanese-style comics drawn without spoken dialogue, which Coamix has organized since 2012. Winners have made commercial debuts in Japanese comic magazines, and the event had reached its fifth round as of January 2016.
Coamix was the parent company of Gutsoon! Entertainment, a now-defunct North American manga publisher that released Raijin Comics. Coamix also published a Japanese-language edition of Raijin Comics in Japan.
Coamix began self-publishing in 2020, after previously partnering with Shinchosha until 2010 and then with Tokuma Shoten until that year.