This is follow on post from Google Firebase detailed security rules part 1. Advanced Rules Only allow user to edit or add their own This prevents other users from modifying other users content. Here's an example of Firebase Realtime Database. "users": { "$user_id": { ".write": "data.child('user_id').val() === auth.uid || newData.child('user_id').val() === auth.uid" } } Similarly... Continue Reading →