What system of IP protections would be suitable to allow private industry to subsidize the expense of developing genetically-modified foods that are able to be planted over and over again after the first purchase? I suspect it will at least resemble patent protection, which at least does eventually end.

It's a very old problem, with parallels with Unix (as I understand it you could duplicate the install media after purchase for free; it wasn't until later AT&T would realize the value of what they were sitting on and try to control distribution of SysV to extract capital from it).

While open-source programmers like myself don't mind volunteering time and code, there is not a comparable contingent of "open-source geneticists" that I'm aware of. That means someone has to pay the piper if they want the GM seeds. If you concentrate the cost in the first batch of seeds you make them prohibitively expensive, which would lead to a gray market of fellow farmers selling their excess seeds at much cheaper cost.

So I don't see buying seeds yearly as a tithe, as much as a requirement of the overall business model given the reality of the large capital investment required. Am I missing a superior alternative?