How do I find official or reliable first-hand sources for which companies produce an anime series? I usually refer to MyAnimeList and Anime News Network, but I cannot find official or company corroboration for some of their articles. Studios usually list their works on their official web page. Is there a similar website for licensors and production companies? Do I need to check the Japanese equivalent of the SEC? The best I could find are third-party non-affiliated sources like independent websites:
Natalie - Comic/manga discussion site.
AllCinema - Blu-ray and listing or schedules.
I want to know which companies pay for and get profit from the show in any way, from streaming to merchandise. I don't think an anime's official website is enough. For example, the website of Zom100 lists the studios and "production company", Shuo Shuisha Production. However, I am not sure if the "production company" refers to a member of the "Zom 100 Production Committee" or just the production assistance company, i.e. the company that handles some administrative jobs.
I want to do research as if I were checking "responsible sourcing." Kyoto Animation Studios is a profitable powerhouse that supposedly avoids underpaying staff. Do they also avoid working with "black companies" that don't share their good practices? I don't know, because I can't find reliable sources on which companies pay Kyoto Animation.