Regarding patents, it is tricky. First, a patent is only good in the country/region it is granted in. Europe, Russia, China are all independent. Unless you have patents granted in all these countries you still aren’t fully protected. And then on top of that, you do something a little different as in using slightly different materials, structures, etc. than the original patent and it may not cover it.
And...
Generally when issued a patent in the US you have to bring it to market within a couple of years or your patent can be challenged and protection lost.
And, to boot, a patent in Russia and China are only as respected as long as the government cares to respect it. The moment those governments want your product, they’ll just take it.