According to Vandana Shiva, seeds are the original renewable resource, until multinational corporations like Monsanto gain seed patents.
Interviewer: "You talk about the fact they are enslaved by the way they are sold seeds."
Vandana Shiva: "...Patents are granted for inventions. Seed is not invented. But the only reason why you take a patent is to collect royalties. Royalites meaning cost for your seed. Royalties meaning seed that is renewable by its very nature is made non-renewable."