And, I'm sorry, but I honestly don't see, from a philosophical standpoint, where the crime would be in this. If this meant that only one family-owned company would create paperclips, then so be it. Or that the family would have to be compensated by any company they allowed to create paperclips, well why not? If the inventor or family chose not to release the product for sale, I'm sure someone else would eventually come up with another product with the same purpose and sell it. So I'm not seeing why it's actually a bad thing that the heirs would own rights to the product.
Then I think we may we have a fundamental disagreement. As a society, we have decided that monopolies are a bad thing. We do not want complete power over a single service, product, resource, etc. to be in a single set of hands over a long period of time. I agree with this. I used the paper clip example simply because it's an innocuous, ubiquitous thing we don't even think about*. The thing is, it's much larger than that.
Allowing the perpetual or near perpetual holding of an idea that may be of benefit to society -- say, a medical breakthrough or important piece of literature -- to be held by a single entity for 100, 120, 140 years (and that's assuming no further extensions) is little different in my eyes. If an important medical device is developed by Joe Blow, do we
really want Joe Blow and his heirs to have sole control over it for multiple generations? For several decades, sure, but for generation after generation? I would submit that the answer is no.
You can disagree, of course. If so, our disagreement is at a core enough level that we can't really go anywhere else on this topic.
I would also submit that the realm of ideas and literature and philosophy and art is just as vital to society as such inventions -- as writers I doubt we'd want to argue any different -- and therefore ought to be treated with a similar philosophy. Maybe not
exactly the same. As noted, I'm in full support of copyright protections for creative works. But philosophically, the two things are not that far removed.
*It would be easy to drum up countless examples of inventions and innovations great and small that are a key part of your life, and are
only a key part of your life because the patent protection ran out, thus allowing others to bring them to the masses. Imagine a world in which all the patents Alexander Graham Bell held (and often stole - but that's another topic) never left his hands or those of his heirs. Or technology for your computer, or radio, or car, or that scan you had at the doctor's office, and on and on and on. Envision a world in which so many of the cornerstones of modern society do not
belong to society. Imagine the ramifications for innovation, for the costs involved, and on and on and on. It shouldn't be difficult to see why this would be a Bad Thing. It's why our laws on patents and on monopolies are the way they are.