The biggest concern I would have with this is that patents exist in large part to fund very long development times, refining ideas (such as Xerox.) All in advan

The biggest concern I would have with this is that patents exist in large part to fund very long development times, refining ideas (such as Xerox.) All in advance of production and therefore licensing or revenues from licensing. If you can interest anyone. In the case of Xerox, innumerable companies turned the invention down. A predecessor company of Xerox was willing to heavily knowing the returns would be spectacular if they were right. To work, the market created would have to avoid collusion (which is rife now and extremely hard to detect or prosecute) and taxes could not be confiscatory (which would be extremely tempting - it's already the case that the filing fee tax is so high that poor people can't afford to patent their ideas, those ideas are given to the first company to copy the idea, swear it's theirs, and file. This may be the major source of economic inequality in the U.S. now.)