Hi,
Some people use the same mautic instance for multiple domain and multiple organizations. We use two uniquie identifiers, one is a specific “contact_owner” custom field. This allows our different organizations to have their own instances of the contacts.
However, I have not managed to set up cookies and tracking correctly for this. Now, tracking data is going to the version of the contact that was most recently registered. This means that one organization will get all tracking data into their version of the contact, and the other organization that have another instance of that contact will get no tracking data at all!
Anyone that knows about a solution for this, is it possible at all? I can try to develop a solution if someone that knows how mautic cookies are working maybe can give me some hints and general ideas of what needs to be done! 
Best,
Samuel