I have been mapping on OSM for a while now but I didn’t add any business’ name. All I ever did was to add the PoI (for example supermarket) without putting the exact name of it; is this a correct behaviour regarding the copyright? As far as I know every company trademarks their name so putting it on the map, without asking directly, would be a violation of copyright.
Though, I see a lot of companies names on the map and it is odd to me that in fact they all agreed to be put there.
PS: I always add places I have visited before and I know about from my personal experience
You might be mixing up copyright and trademark here. A business can have a trademark on their name, so nobody else can set up a business under that name; the “nominative use” of the trademark (where you refer to that particular business by that name) is always ok though. So you can write in your public diary that “today I had food at McDonald’s” without worrying (or at least the worry would not be about a potential trademark violation…). Same with maps - we are free to put the name of a business on the map if that is the name they are trading under. This even applies to businesses run by an individual - while we would not map “John Doe lives here”, for privacy reasons, “John Doe Carpentry” is fine to map.