An issue that's come up while we've been cleaning up our records for GDPR - we have a significant number of records where organisations have been entered as individuals, and vice versa.
This is mostly through user error - for example from records bulk imported as individuals, but also because individuals use an organisation email to sign up or contact us, or we only have an individual contact email for an organisation.
However, there is duplication between these contacts, and testing on CiviCRM I realise that if you create a new individual contact with the email of an existing organisation, 'Check for Matching Contacts' doesn't find the existing organisation. And, of course, the dedupe rules can only be run on either individuals, households or organisations.
Is there any way to set a dedupe rule across all contacts? e.g. a basic check to see if an email is already on the system?