The deal cThe U.S. and the European Union reached a preliminary deal to allow data about Europeans to be stored on U.S. soil, heading off a growing threat to thousands of companies’ trans-Atlantic operations. The deal, announced Friday by President Biden and European Commission President Ursula von der Leyen, could if concluded resolve one of the thorniest outstanding issues between the two economic giants. It also assuages concerns of companies including Meta Platforms Inc. and Alphabet Inc.’s Google that were facing mounting legal challenges to data transfers that underpin some of their operations in Europe.