After a one-and-a-half year investigation, the U.K.’s Information Commissioner’s Office (ICO) has ruled that instant message platform WhatsApp doesn’t have a lawful basis to share its users’ personal data with its parent company Facebook.

The ruling marked the conclusion of ICO’s investigation into whether it was legal for WhatsApp, which hadn’t yet started sharing data with Facebook, to share data under U.K.’s Data Protection Act of 1998, which is based off the European Union’s 1995 Data Protection Directive.