Irish investigators said TikTok did not protect the data of users in the European Union, improperly transferring some of it to China. TikTok said it would appeal.

European Union privacy watchdogs have fined TikTok 530 million euros ($600 million). They say a four-year investigation found that the video sharing app’s data transfers to China breached strict data privacy rules.

The social media giant said on Friday that it disagreed with the fine from European authorities and planned to appeal.