It's not illegal to arbitrage but yeah I think what you are pointing at is you have to be regulatory-ily buttoned up for Japan markets vs a more loose market where you don't have to be super careful & can learn as you go.

So SBF having been in finance before (Jane Street), he knew where the footsteps were and how to do it vs a fly-by night crypto investor with no finance background.

Supposedly the Japan “subsidiary” (if you can call it that) was set up by a Japanese person and a resident of Japan, who was a contact of SBF through the Effective Altruism thing. I think they knew something was shady, because the account they had opened in Japan was with a small rural Japanese bank.

When that “arbitrage” turned out to be really lucrative one of the founders of Skype (Talinn something) gave SBF a $50 million loan. SBF and that Talinn guy knew each other also from that Effective Altruism sect-like thing.

All this info was part of a Sequoia congratulatory piece on SBF, they of course had also given him money. The article has since been taken down, it’s still reachable through Web Archive.

> The article has since been taken down, it’s still reachable through Web Archive.

I've skimmed through it, and by god, I was surprised Sequoia wasn't crediting the sun rising each morning to SBF.