Another valuable example of this is a patent pool consortium, a corporation that exists to bring all patents in a field together for easy licensing.
"Reduce inventions to practice?" First, I don't think that my country has any such legalese in our patent law. Second, what does that make NVIDIA? Or ATI? They don't make their own chips either. Third, I believe that what is protected by most of these patents are neither HDL files nor the chips but rather specific implementation techniques for parts of the HDL implementation of the ISA. If the chips were patented, it would be worthless because you could do an independent design.