Quoted from Gryszzz:
One of you lawyer bastards needs to get up with Ninjacamp on that free advice as he needs to patent/trademark his shit asap.
Many thanks for the ingenuity
It's really not practical on a product this niche. Legal costs will substantially reduce or obliterate (depending on demand) the income from the item. Plus there is prior art from Cliff (the OG) and Stern and JJP with the only change being the material (a kind of plastic, but mylar is a plastic with extensive prior art with this use, too), which may not be enough to successfully defend the patent even if it IS awarded.
And policing patents you own can be a VERY EXPENSIVE enterprise. There's a company I bought stock in with a seminal patent on DDR memory that underlies every stick sold since DDR2 that EVERYONE that used DDR2 and up (computers, phones, servers, EVERYTHING) owes royalties to. Google was shown the tech and ripped it off, got tremendously wealthy with the speed advantages and spent the last 13 years trying to bankrupt the company so they did not have to pay royalties. That is JUST now getting to a money judgment trial after finally getting a guilty verdict against google who exhausted all appeals last year. And this is on a patent worth tens or hundreds of BILLIONS of dollars. 13 years. Tens of millions spent to get justice.
So yeah, it's not an easy road, or a cheap road (or a recommended road, here), and if Stern wants to dick them around like they did to Cliffy with his OG protectors they flat out ripped off, there's little they can do about it without a LOT of money, probably more than they will make from these and related products. Essentially they just have to rely on the quality of their product and the propensity of the pinball community to support originators that move pinball forward.