Soybean seeds aren't finite like fossil fuels. They're specially grown. If you don't want to use patented seed, don't use it. Use organic seeds if you want (and many farmers do). Otherwise, pay the IP holder. Monsanto isn't a monopoly, and you have several other GM competitors to choose from.

Patent problems are no secret around here, but I'll reiterate one of the key points: Patents deal with possession of technology, not the implementation. In other words, if I violate someone else's patent in a product, and you buy it, you have become liable for the violation.

Now, with that said, you cannot possess GM seed without the necessary license agreements with Monsanto due to the above. Theoretically farmers, who have acquired the necessary licenses, could grow second generation seed, except those license terms provide additional clauses around the use of the second generation seed. You can disagree to those clauses, but then you will not be granted access to the patent rights.

So, the issue is that you cannot buy GM seeds in the first place without entering into a legal agreement, and that legal agreement dictates how you use future generations. There is no scenario where the second generation can be logically free of IP rights, because if you disagree, you cannot reach the point of growing a second generation.

Of course the real issue here is that the patent system needs to be fixed, and not just for seed and software.