After a significant data theft at UnitedHealth, fellow healthcare company Kaiser Permanente publicly announced a data breach impacting 13.4 million current and former insurance members. Kaiser’s systems accidentally shared patient data with third-party advertisers. Those advertisers include Google, Microsoft and the social platform X.

The shared data included names, IP addresses, pages people visited, whether people were actively signed in, and the search terms they used when visiting the company’s online health encyclopedia. Kaiser has removed the tracking code from its sites that caused the beach. While the breach wasn’t a hacking event, the incident is still concerning from a security perspective.

Read More: Kaiser Insurance Leaks 13.4M Members’ Data to Online Advertisers