But it was unclear how bulletproof those treaties would be under the new ruling, which cannot be appealed and went into effect immediately. Europe’s privacy watchdogs, for example, remain divided over how to police American tech companies.France and Germany, where companies like Facebook and Google have huge numbers of users and have already been subject to other privacy rulings, are among the countries that have sought more aggressive protections for their citizens’ personal data. Britain and Ireland, among others, have been supportive of Safe Harbor, and many large American tech companies have set up overseas headquarters in Ireland.