In my opinion (not worth much), it isn't UNLAWFUL to carry into a business with a "no guns" sign because that is only a policy that a private business has adopted (not statute). Now if they ascertain that you are carrying and ask you to leave, I think you must comply with that request as they are the owner of the private property.
This statement of opinion doesn't apply to those places listed in the SDA as prohibited places. If you are caught carrying in those places you will most likely go to jail.
That being said, if you work at the particular place of business (OG&E) and it is posted then that is a different story because they are your employer and could be terminated for violating company policy (but you already knew that)
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