&gt; <i>In future we plan to have a third separate addressbook for automatically added email addresses.</i><p>I just want to say that this is something I really want. I don&#x27;t even care if it&#x27;s exposed over CardDAV, I just want to get automatically-added addresses out of my normal user addressbook. A couple of weeks ago I realized that my addressbook had a bunch of contacts in it I didn&#x27;t recognize, so I cleared them all out. Today I checked and there&#x27;s 3 more unwanted contacts.<p>It actually feels very broken to me that FastMail is automatically adding things to my address book without asking me, and without any obvious way to turn it off. I don&#x27;t mind it recording this stuff in a separate addressbook to use for spam filtering and for auto-filling during message composing, but it should not be part of my normal addressbook and should not be coming down over CardDAV for my user addressbook.<p>The reason this is a problem is because I use my FastMail CardDAV addressbook as a shared addressbook for me and my wife (she doesn&#x27;t use FastMail herself but I do), since we use iCloud for our normal address books but iCloud doesn&#x27;t have a way to share addressbooks. It occurs to me now that since I&#x27;m actually using a Family account (for a single user, so I can have a custom domain without having the more expensive plan), I have a Shared address book available and I should just switch over to that (since I assume nothing ever auto-adds there). But it was still a rude surprise to find a bunch of unknown contacts appearing in my Contacts app on iOS.