https://www.bleepingcomputer.com/news/security/numerous-sites-leak-user-emails-to-advertising-analytics-services/

Multiple online services and products are leaking email data belonging to their users to third-party advertising and analytics companies, shows a recent research published today.

Websites mentioned in the report include Quibi.com, JetBlue.com, KongHQ.com, NGPVan.com, Mailchimp’s Mandrill.com, WashingtonPost.com, Wish.com. Between them, there are hundreds of millions of emails.