I thought I came up with a new invention but unfortunately found that it was already patented in China. I am in the US and it wasn't patented here. I was told that I could in theory, build and sell the product anywhere that the patent wasn't filed in. If I do decide to do this, does this mean that I can do this and only hope the inventor doesn't decide to then file a patent in the US after I already began selling the product? I assume if they ever decide to file here, the moment it goes through, the business is screwed if they also decide to fully block any use of their idea or in the best case, ask for royalties?
If this is the case, I personally find it profoundly contradictory that this is possible. One reason to patent is to tie your name to an invention so you get credit and another is to protect your idea from copy. If someone can just make your invention in any other country and sell it because the patent in the origin country isn't recognized there in terms of actual creation purposes, it's disengenuous to then also say "oh you can copy and sell it, but you can't patent it". Yeah it's not original by that point, but the real purpose now is legal protection for business purposes because it's just a risk to put in all the time and effort to making the idea reality and starting a business around it, just to have someone come in at any time to shoot it all down (Especially annoying when they have done nothing in any other country or even their own to signify that they wish to make something out of it either). I'd say just make it consistent in both areas: Either have a patent and the legal protection for copying be globally applicable or allow for patentability and copying everywhere else besides the origin nation the patent was filed in. Seems more consistent that way.