Passporting is why a broker licensed in Cyprus under cysec or Ireland can onboard clients across the European Economic Area without separate authorisations. UK firms lost passporting after Brexit and now rely on national regimes or EU subsidiaries.
Reverse solicitation is the exception firms lean on when they are not licensed locally: if the client initiated the relationship without any marketing, the service may be lawful. Regulators read it narrowly, and any advertising, affiliate link or influencer promotion aimed at that country usually destroys the defence.
For traders the practical question is which entity your account is with. The entity on the client agreement determines the regulator, the protections, the leverage limits and where a complaint goes, regardless of the brand on the website.
Related: cysec, esma, mifid-ii, client-categorisation, fscs-protection