Presumably France, since that's where they're based.

Gandi is also incorporated in the US.

----- Legal Notice The owner and publisher of this website is Gandi SAS, a simplified joint-stock company registered under French law with a capital of 37,000 Euros.

Registered with the Paris RCS – French Trade Registry - under number 423 093 459. Intracommunal VAT number FR81423093459

Headquarters: 63-65 boulevard Massena, Paris (75013), France Telephone: +33.(1)70.37.76.61 Fax: +33.(1)43.73.18.51

US office: Gandi US Inc. 124 Lakefront Drive Hunt Valley, MD 21030 Fax: +1.410-449-4499

The US office is a subsidiary. I don't know the legal requirements, but I believe that in the worst case scenario both US law and French law would apply. It is my understanding that the registrar is still the French company, therefor subject to French law.

IANAL.

So I cant register a domain there and sell memorabilia from Nazi Germany, right?

French penal code.

This is an important concern for any US citizen who may migrate their domains to a Gandi. French law differs dramatically from US laws when it comes to matters of libel, slander and privacy.

Why does this matter? If your a US site, and you piss off someone in France then the pissed off individual has a target local to them (Gandi) who they can send legal threats to based on French laws. Or really a mixture of US and French laws.

If you would like to look up more on the subject when dealing with international law conflicts, consider reviewing US-EU safe harbor.