Deleting old addresses?

I keep seeing in these threads to delete old addresses because it might make it harder for disputes to be verified. I understand that concept but...

Do CRAs have to remove old addresses? Is there something that requires them to remove previous addresses? Do they only need to keep the current one? It seems that they like to keep track of the old addresses and in my case, they are valid addresses. I would really like to not have a record that I lived in some of those places though.

Does anybody have an example of the letter to write asking deletion of the old addresses?


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Annuity