Google on Tuesday will appeal an order to extend the European Union’s “right to be forgotten” to its search engines across the globe, arguing before the EU’s top court that the order encourages countries to assert sovereignty beyond their borders.

National laws used to stop at the border. In cyberspace, they increasingly stretch around the world, as regulators in Europe, the U.S. and Canada have started asserting legal authority over the internet across country lines.

That is thrusting global tech firms like Google, Facebook Inc. and Microsoft Corp. into a potentially costly legal morass, and setting the stage for conflict over who will—or should—regulate everything from free speech and privacy to cybercrime and taxes.

The Google dispute before the EU’s Court of Justice in Luxembourg is the highest-profile case yet to test where jurisdiction begins and ends when it comes to data. Google is appealing a 2015 order from France’s privacy regulator, CNIL, to extend the EU’s “right to be forgotten” to all of its websites, no matter where they are accessed. CNIL fined Google 100,000 euros ($116,295) when it didn’t comply.

France argues that the right—which allows individuals to request removal of results that include personal information from searches for their own names—is empty if it can be dodged by spoofing one’s location, for instance by connecting to a VPN. Google, a unit of Alphabet Inc., says France’s demand risks allowing the censorship laws of dictators and tyrants to dictate what people around the world can see online.