BOOM! Studios ignores unsolicited submissions, and its terms license to BOOM! any idea sent in anyway. It bought Archaia and has licensed Power Rangers and Firefly for comics.
“Please note: BOOM! does not accept unsolicited submissions and all submission messages will be ignored.”
“In your communications with Company, please keep in mind that we do not seek any unsolicited ideas or materials for products or services, or even suggested improvements to products or services, including, without limitation, ideas, concepts, inventions, or designs for websites, recipes, products or otherwise (collectively, “Unsolicited Ideas and Materials”).”
What you agree to by sending something
“Any Unsolicited Ideas and Materials you post on or send to us via the Service are deemed User-Generated Content and licensed to us as set forth below.”
What it has bought from outside
2013
Archaia Entertainment, kept as an imprint
“Boom! acquired Archaia Entertainment in June 2013 and made the company an imprint. [ 113 ]” en.wikipedia.org
2015
Mighty Morphin Power Rangers comics license
“…Boom! acquired the license for Mighty Morphin Power Rangers in June 2015 and released a monthly comic starting in January 2016.…” en.wikipedia.org
2018
Firefly comics and graphic novel license
“In July 2018, Boom! announced that they had acquired the comic book and graphic novel publishing license to Joss Whedon 's Firefly with plans to release new monthly comic book series, limited series, original graphic novels and more. [ 93 ]” en.wikipedia.org