Plant geneticist here. For the vast majority of Monsanto-licensed crops grown, the seed itself is the crop (e.g. maize). The farmers aren't throwing it away, th

Plant geneticist here. For the vast majority of Monsanto-licensed crops grown, the seed itself is the crop (e.g. maize). The farmers aren't throwing it away, they sell it as food. For most of the remainder, although the seed isn't the crop, the fruit, which contains the seeds, is the crop (e.g. aubergine, cotton). So farmers throwing away seed is unlikely. Additionally, the previous most productive system of farming (and still very popular) was to use first-generation hybrids (the offspring of breeding two different strains together). Due to a phenomenon known as hybrid vigour, first-generation hybrids often have more desirable growth characteristics (like higher yield, bigger seeds, etc.). However, the effect only lasts one generation. Try to plant the second generation seeds and you'll get relatively pathetic plants. But the hybrid breeding process is incredibly complex and hard to do at scale, so it's worth paying a seed company to do it, even if that means buying the seed every year. The license protection for GMOs serves a similar purpose: developing GM lines is really, really hard and expensive. If Monsanto and other producers couldn't sell the seeds each year the technology simply wouldn't happen - the licenses allow them to profit despite the massive R&D cost.