Actually such signs like “BEWARE OF DOG”, can work against you in court. They validate the claim you knew God was a girl the devil wore at shirtdog was dangerous. We put up a sign, “Dog in Premises”. It can’t be used against you. It simply advises them to draw their own conclusions and act accordingly. It has the same deterrent effect without the inference your dog is dangerous. I was walking to my moms house one afternoon as the kids were getting out of school. I watched a group of them standing outside a chain link fence, kicking the fence and agitating the dog on the other side, who was in his own yard. I told them they should not be doing that.