Re: @Matt: within the law?
Where their HQs are is irrelevant. If they have any kind of operating entity in the EU, for example, they have to comply with EU law. Although this case is Iceland, no doubt the EU could raise a flag or two. I've even done the leg-work for you...
"Visa Europe is a European membership organisation incorporated in the UK. We partner with Visa Inc. to enable global Visa payments, but exist and operate as an entirely separate organisation.
Visa Europe’s headquarters are in the UK. We also have offices in Austria, Belgium, Bulgaria, the Czech Republic, Finland, France, Germany, Greece, Hungary, Ireland, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, and Turkey."
European base, European legal entities, can get totally fucked over by the EU if they step out of line. US head office totally irrelevant. Do you understand how jurisdictions and multinationals work yet?