Kaiser Health System Sent Private Patient Data to Tech Giants

The giant California-based health plan Kaiser Permanente said its websites and apps may have inappropriately sent members’ private information to tech giants including Alphabet Inc., Microsoft Corp. and the social media company X.

Kaiser plans to inform 13.4 million current and former patients of the breach directly over the next month, according to an emailed statement to Bloomberg News. The data shared with other companies may have included their names and what people searched for on their computers. A US government website for health-data breaches described the incident as an “unauthorized” disclosure.

Health companies are facing scrutiny over ...