LONDON (AP) — The European Union’s top court ruled Thursday that an agreement that allows big tech companies to transfer data to the United States is invalid, and that national regulators need to take tougher action to protect the privacy of users' data.

The ruling does not mean an immediate halt to all data transfers outside the EU, as there is another legal mechanism that some companies can use. But it means that the scrutiny over data transfers will be ramped up and that the EU and U.S. may have to find a new system that guarantees that Europeans' data is afforded the same privacy protection in the U.S. as it is in the EU.