Hi Dusty,
Looks like you stumbled on an issue I discovered last week.
You know how when you get a new client and log into dash you'll sometimes see one or more listings that are pending action, sitting waiting for some old pin that they never entered? OR they will have several dupes they suspended?
Well guess what? Now that we are in the world of G+ with everything tied together,
all those listings - unverified in dash and even suspended.... create G+ pages.
YEP even if suspended OR unverified in dash.
Last week I searched G+ (People and Pages) for a Dentist I worked with a long time ago and found like 7 G+ pages. I thought I remembered him having some unverified and suspended listings in dash. Think way back when there were only a couple and I said if not verified, don't worry, just leave them. Well he's had massive dupe problems and had a habit of claiming the dupes and suspending to try to get rid of them.
When doing consulting I have seen MANY dashboards with like 8 dead listings in there, some unverified and some suspended. But didn't think it was a big deal. If not verified or suspended, assumed they just did not exist.
Well they do. They exist as G+ pages I guess. I'm calling them REMNANT G+ pages - as in just left over scraps of data, that don't really do anyone any good.
I reported to Google and we discussed, but they didn't think it was a big deal because those pages are not very discoverable, unless someone searches by name in G+ (under people and pages.)
OK so all those extra dupe G+ pages won't hurt ranking because they are just G+ pages so they don't rank.
And aren't a Places violation because they are either not verified or are suspended, so are not active in dash.
However IF a customer searched for them in G+ because they wanted to follow them and IF they picked the wrong page your client could have followers scattered on different G+ pages and there is no way to merge pages or move followers.
So if you like to keep things tidy and organized might want to clean old dead listings out of dash.
IDEA - Search for the business name in G+ and then select "People and Pages". This could possibly also help alert you to other dashboards or could be helpful in hidden merged dupe discovery. Because if the dash they gave you log in to only has one listing, the listing you are managing, but G+ shows 4 then you know there are other listings in other dashboards somewhere. BUT warning when you research those G+ dupe pages you need to know how to tell what type of page it is - personal profile, brand, local unverified or local merged with Places, etc.
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OK so above is some general info and my thoughts and observations. Now back to your client above...
If you've cleaned up the dash you manage and there is only one listing in there. No unverified or suspended listings, then I suspect the client has another dash with all those listings sitting in it. Or possibly a previous SEO?
But 3 are verified? Do they have multiple locations? Ya I just checked that looks like the case.
If you can find suspended or unverified listings in dash, want to delete them and see if the G+ pages go away?
Either way these aren't a huge deal and likely won't cause problems. But I'm seeing more and more folks at the G forum saying I found this G+ page I never created and it's not in my G+ dashboard so how do I get rid of it? Was starting to wonder what was causing the issue.
So now you know, if this ever happens to you, it's likely an unverified or suspended Place page listing that left a remnant G+ page.