After the creators of the myPersonality app, which gathered information on more than four million people Facebook users refused to be audited, the social media company banned the app in a purge that saw 400 additional apps suspended.

“It’s clear that they shared information with researchers as well as companies with only limited protections in place. As a result, we will notify the roughly four million people who chose to share their Facebook information with myPersonality that it may have been misused,” Facebook Vice President of Product Partnerships Ime Archibong wrote in a blog post. 

Notification won’t extend to friends of those users, though, “given we currently have no evidence that myPersonality accessed any friends’ information,” he said, noting they would be contacted “should that change.”

The 400 suspended apps were among thousands that the company has reviewed since March, after bolstering security and privacy policies in the aftermath of the Cambridge Analytica scandal in which the data analytics firm violated the social media company’s policies by collecting the personal data from tens of millions of Facebook users without their permission.

Assessment of the 400 apps recently suspended raised “concerns around the developers who built them or how the information people chose to share with the app may have been used — which we are now investigating in much greater depth,” Archibong wrote.

The discoveries have prompted Facebook to change a bevy of policies, including expanding its App Review and instituting a new policy preventing information to be shared with apps that have been used in 90 days.