I have an app “lawyers near me”. Lawyers sign up and add their business name, address etc. I have a filter that groups all lawyers working for a company by door number and post code. I don’t ask them if they already work for any of the published companies, even though on the company business page I bring all lawyers associated with the postcode and show them as working for company/firm X. I had a few reasons for going about things the way I did such as lawyer verification, pricing strategy etc.
Your approach was my first option but my requirements had other options on mind.