If you are referring to a case where litigation was executed under the terms of patent contract, the farmer – being a member of the public who grants such paten

If you are referring to a case where litigation was executed under the terms of patent contract, the farmer – being a member of the public who grants such patents – has still entered into a contract by virtue of choosing to be a member of the public who has agreed that patent contracts are desirable to issue. The public had no obligation to issue the patent, but chose to. The farmer need not be a member of that public, but chose to be.