It happened first in /b/ with a forum called stormfront, they sent kids to troll with fake pedophilia threads, porn, racism, because /b/ was kind of getting the habit of trolling racists. The nazis then lured kids with fight club memes and shit like that, and THEN they got the idea of spreading their ideology by tricking kids into trolling with racism, doing their propaganda. Spreading to all the boards, 24/7, and with their people infiltrating the administration ranks as mods and janitors.

Between that, Gamergate ocurred. It first started as a protest against journalism corruption, gamers knowing the journalist was making favors to her friend, it then exploded with false flag attacks, slowly turning away the original protest to something she could manage to put against gamergate, like it was mysogisnm.

Of course normal spam had its way in. In /g/ we have a group of trolls, which are most likely sent by marketing agencies to spam, and is most likely this happens in /tv/ and /v/ with every publicity campaign.

Years pass and then a new administrator comes, but Hiroyuki Nishimura has problems of his own, which affects us all and the future of 4chan and the free internet. Years ago, Hiroyuki Nishimura had his own forum called 2ch, the inspiration for 4chan, but he lost the ownership to the web domain in a very complex scam. Hiroyuki Nishimura was tricked by Jim Watkins, a former military, who owned 2ch servers but not the forum itself. Watkins made a silent coup on Hiroyuki and took over his domain. Later on, Jim Watkins offered free hosting to eightchan's former owner, hotwheels, but during a mysterious DDoS to the website he deviated the traffic to a domain of his own, nobody noticed. He is now the owner of eightchan, the wheel guy is no longer the owner, just a janitor with high privileges (or not so).

But what is the thing about Hiro stealing info about? It's because when someone on the old 2ch figured they were getting their info sold, THEN they realized Hiro wasn't the owner of the old 2ch domain anymore.