Hi Miriam,
Thanks for your response. My client DOES have a suite number. It's "Suite 400". There are several other businesses with the exact same address and suite number, because they all share the same office.
My point about #400, was that in the two other listings I came across for the businesses that share this address, Google has changed the adress on each of ours from Suite 400 (the official address) to #400. I was wondering if that could be some sort of signal: clearly Google recognizes these as the same address. Google hasn't merged our listings, but has tweaked the address slightly so that all appear exactly the same as #400. I could very well be looking for clues that don't exist
Since the location is not a mailbox, but a legit office space, to my understanding that's not against Google Places guidelines. It's difficult to find specific wording from Google, but I found this:
"Businesses with multiple specializations, such as law firms and doctors, should not create multiple listings to cover all of their specialties. You may create one listing per practitioner, and one listing for the hospital or clinic at large."
It would stand to reason that if a law firm can create separate listings for each practitioner, separate businesses that share an office would be able to create separate listings, as well. It says nothing about tweaking suite numbers and things like that. Clearly Google would never openly endorse that.
At this point, I'm not really worried about being penalized. I'm much more worried about being merged. And I'm even more worried about simply being stuck on page two.
I should also note that we have earned a fairly dominant first page position (organic and blended) for state-specific queries, as well as queries for their other office locations, a couple of which are also shared offices. All of these queries are less competitive than queries for the main location we've been talking about.
I'm also reluctant to change the address because I don't want to end up in a "pending" limbo for months -- which has happened to this client before with duplicate listings created by previous SEOs.
Thanks again for your thoughts.