ACCS labels Haruka Yume no Ato as the largest among these leech sites in Japan, and it allegedly linked to sites that contained illegal copies of manga.
The ACCS values the amount of copyrighted content linked from the site from July 2016 to June 2017 as worth 73.1 billion yen (about US$645 million).
Five of the suspects allegedly administered the site, and four allegedly contributed unauthorized content.
Police agencies from Osaka, Saitama, Chiba, Kanagawa, Niigata, Okayama, Kagawa, Ehime, and Fukuoka were involved in the investigation.