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As in the following:
Some people on there appear out of nowhere, ones I have contacted years ago once through my associated Gmail address. I'm assuming I'm appearing on their wall(?) as well.
Is there a setting that controls whether or not I want to be on such a "suggested contacts" list?
There is just a possibility to untick the "Help others to find my profile in search". That hides your profile also from these lists.
Google Support on topic: https://support.google.com/plus/answer/1151728?hl=en
Or remove those people from your Gmail "Other contacts".
