Open Radar

 
Summary:
After installing the OS X 10.9.4 update today, when I open the "Updates" tab of the Mac App Store, it shows a pending update for the App [REDACTED] I'm the author of. 
It shouldn't show that update because it has been installed on this Mac months ago, but the problem that's really bothering me is the following:
When I try to install that update anyway, Mac App Store requests the Apple-ID password of an user account I have absolutely nothing to do with and have definitely not typed in on my Mac ever before (see attached screenshot).
The person [REDACTED] is not me, and I am not associated with that Apple customer in any way but the following:
The only connection to that Apple-ID I can draw is the fact that this is an user I have sent a Promo Code for another (not the aforementioned app [REDACTED] but an app named [REDACTED], ID [REDACTED]) in the past. The user used the Promo Code to install my App [REDACTED]. But this obviously shouldn't be reason enough to have their Apple-ID displayed on my Mac at any time!

Steps to Reproduce:
I guess this problem is local to my environment, so I cannot really give steps to reproduce. Please contact me if you need additional information.

Expected Results:
Mac App Store should never ever show the Apple-ID login of another user to me.

Actual Results:
Mac App Store displays the Apple-ID of a to me completely unknown user - if I wasn't a programmer and knew that such problems can happen, I'd probably (and rightfully) freak out!

Version:
App Store 1.3 Build 201.7
Mac OS X 10.9.4 Build 13E28

Notes:
Please do under no circumstances contact the owner of the [REDACTED] Apple-ID as I do not want my customers to believe that there are security implications when using my app when in reality it is a Mac App Store problem.