A principal who has reason to keep aspects of their life separate often opens accounts with that separation in mind. Different email addresses; different names where appropriate; different phone numbers; different addresses; different payment methods. The intention is that the accounts belong to different categories of the principal's life and do not lead back to one another.

The accounts nonetheless turn out, in many cases, to be linked through identifiers that the principal did not consider. The same device was used to access them; the device's identifier was recorded against each account. The same network address connected them; the network identifier was logged. The same payment processor handled the financial transactions, which were linked through the processor's records. The same recovery email was used as a fallback. The same phone number was registered as a verification route.

The linkage is rarely visible from the principal's side. The accounts continue to function separately; the categories of the principal's life continue to feel separate. The linking is done by parties whose business is to combine records, and whose customers want the joined picture rather than the separated one.

The principal sometimes discovers the linkage in unexpected ways: a recommendation that suggests they connect with someone who knows them from a different category of life; a piece of marketing that arrives at one address that depends on information from another; a verification message that arrives at the wrong inbox. Each is small. Each suggests the linkage was already there.

The work here is patient. It begins with an audit of the identifiers the accounts presently share, which is often more than the principal expects. It continues with the deliberate separation of the routes the accounts use for verification, recovery, and routine notification, so that the categories of the principal's life are genuinely separate to the parties who combine records, rather than only to the principal who manages them.