Who does regulation B apply to?

Good day, could you please clarify for me who exactly does Regulation B apply to? I'm trying to understand the scope of its reach and how it may affect different stakeholders in the cryptocurrency and finance sectors. Would it cover individuals trading cryptocurrencies as a hobby, or would it mainly target institutional investors and large-scale operations? Additionally, does it have any cross-border implications, or is it focused solely on domestic activities? Your insights would be greatly appreciated.