The straightforward answer is "Yes." While the sign clearly states not to copy such keys, there are no laws that prevent us from doing so. In addition, the engraved message on these keys is not legally binding but only a recommendation.
However, if your key is a registered master key, a patent protects its design and is valid for up to 10 years. During this period, locksmiths permitted to make copies are the only ones allowed to cut this key legally. So, unless your key is a registered master key, we can make a copy of it. However, to protect our interest, we might require proof of property ownership to the key belongs in these instances.
For further questions, do not hesitate to reach out to us.