Can you tell by the signage if the different retailers that you shop at have one owner?...

For example, do Tom’s Toy Store, and Mary’s Toy Store, and Lindsey’s Toy Store, have to have a common logo, or some other indicator that they are owned by Bob? Or do you have to do internet search or some other kind of search to find out? Is there a disclosure law in your region that makes it impossible to hide the monopoly?