A well known problem
Google Maps' merging problems are well documented and have been going on for a long time. Despite more and more businesses experiencing merging difficulties, Google are still not doing anything about the problem. There are a number of ways to unmerge your listing, but they aren't guaranteed to be successful. However, if your business listing is merged with an unclaimed listing and you aren't worried about the morals of removing the other listing, there is something that you can do about it.
Use the merging problems to your advantage
Create a duplicate listing
Paradoxically, the first step is to create a duplicate listing of the business that you are merged with. For anyone who isn't familiar with creating a listing, you can follow the process in our blog post 'how to claim your Google Local Business listing'. You must use the exact same information as the listing that you are merged with, with one small difference. A listing must be verified by Google, which they will do by phone, SMS or post. When creating the new listing, you must enter the phone number and address the same as the listing that you are merged with. This means that you'll need to enter your own mobile phone number. Create the listing and verify it by SMS. You'll then just need to wait.
Playing the long game
It must be said that this isn't a quick process. Once you've created the duplicate listing, you need to wait for Google to merge it with your duplicate. This can take up to 4 weeks. You'll be able to verify when this occurs by looking for your own mobile phone number in the listing that is causing your problem.
Once you're sure that the two listings have merged, simply log into your Google account and turn off the listing. Again, this may take a few weeks for Google to fully action, but once they have done it, your own, unmerged listing will now show on Google Maps and Local Business and the listing that you were merged with will be gone.
The Morals
There are two sides to the morals of this argument. Is it right for you to remove another business's listing just because they are merged with yours and you know more about the Internet than they do? This isn't really fair on the other business, but it also isn't fair on you to have your business details merged through no fault of your own. Is it right for Google to add your listing, often without consent then show incorrect details with virtually no support or help for when things go wrong? Until Google get their algorithm sorted, I don't think that businesses have any choice. After all, you're only removing them from Google Local/Maps, not Google search. And a merged listing may not even be from your local area.
Remember the 11th commandment
A final word of warning - remember the 11th commandment - 'thou shalt not get caught'. There is no word from Google on what might happen to anyone removing local listings that don't belong to them, but it's just not worth the risk. If you do decide to go ahead and claim another listing, don't use the same Google account that you use for your own business. Create a brand new Google account to minimise any risks to yourself and your business.