EU privacy watchdogs seek answers from WhatsApp and Yahoo about users' data

European Union privacy watchdogs have warned WhatsApp CEO Jan Koum to stop sharing users' data with parent company Facebook until they investigated whether the transfers comply with EU data protection law. They also want Yahoo's Marissa Mayer to come clean about recent leaks and spying allegations.In an open letter to Koum published Friday, an umbrella group representing the EU's national data protection authorities expressed its serious concerns at the way WhatsApp users were informed of change