If we're going to run with this 14 year old topic, I don't recall the last time I saw a "No Guns" sign on any business that I frequent in Colorado Springs. The only exception to that is my wife's doctor's offices and the VA.
They used to have them at our bank but on the front door the sign was in black lettering on a black door at the bottom of the door and you had to be looking for it to see it. The side door they had a traditional Gun Buster sign but it was literally at the bottom of the door. I never asked but it was like they were going out of their way to make it difficult for you to see the sign. So they were following corporate policy but not actually restricting you from having a gun in their Bank.
FWIW I ignore the signs entirely when I take my wife to the doctor and I abide by them to the letter when I go to the VA. I rarely go to the post office but I abide by the rules there too.
In NC the law states "On any private premises where notice that carrying a concealed handgun is prohibited by the posting of a conspicuous notice or statement by the person in legal possession or control of the premises."
I have over the years seen some guidance with specific recommendations as to:
- how large the sign needs to be;
- a maximum of how far from the door the sign can be; and
- how far from eye level the sign can be, but I don't think any of it is legally binding.
But, while "conspicuous", while a bit vague, is the requirement. If it's not conspicuous and you have to search for it, it can be ignored.
For example, one of the malls in the area had every door posted, except for an anchor store that sold guns. you could consequently, enter there and access the entire mall without ever seeing a sign. They eventually added a prominent sign at the inner exit from that store to the mall.
I've also entered posted businesses where i did not see the sign until I was exiting, as a sale or promotional sign placed in front of the door obscured the "no firearms allowed" sign. Again, not conspicuous.
We do have several chains that in the wake of those really short sighted and frankly stupid 2A demonstrations, posted their premises against open carry. In short, they don't object to you carrying a gun, but they do object to you doing it in a way that makes other customers uncomfortable. I fully support that as my right to carry also comes with responsibility to wield that right responsibly in a manner that doesn't infringe on the rights of others, like other customers feeling comfortable, and business owners making money in their business.
It demonstrates the value of concealed carry in exercising your right to self defense, without bothering anyone.
And when it comes to entering a posted private business, accidentally or otherwise, concealed is concealed, and if it's concealed you're most likely going to avoid any legal entanglement.
State and federal buildings, county courthouses, post offices, etc, that's a different story with much higher criminal stakes. And they usually have security guards to handle the safety aspect of it.