Small Firms Worry, as Big-Data Pact Dies

Oct. 7, 2015 6:17 p.m. ET

Technology giants hardly flinched when news broke on Tuesday that the European Union's highest court had struck down the 15-year-old agreement that allowed U.S. businesses to transfer Europeans' personal information to the U.S. But many smaller companies were caught flat-footed.

TheMobileYogi, which offers a collection of apps for yoga aficionados, wasn't prepared. The Ohio-based software developer has about 200,000 users, and Chief Executive Sebastian Holst suspects that one-third of them might be in Europe. He says he thinks so because the company collects a mobile-device identifier that is generally associated with a region or country and the rough