Quoted from toyotaboy:I'm not a lawyer, but even if you could patent a layout, firepower is 35 years old. I don't know that it would fall under trademark either. Most of the things that planetary pinball defends it's IP over is art and sound, which fall under copywright which is life of author plus 70 years:
https://en.wikipedia.org/wiki/Public_domain
That won't stop rick from sending you an angry PM.