Copyright law prevents protected material from being republished and sold as new. People own books that they purchase, they can make margin notes on them. They can sell them to used bookstores for resale. They cannot take that material and republish it without compensation to (and usually permission of) the author (the same applies with music). And the same applies to coded material.
A buyer is not permitted to republish codes in other formats or media for profit. But that is as far as copyright law takes you. It is ownership of the abstract intellectual commodity... not the concrete medium on which it is printed that is protected. John Deere will get nowhere if that's what they are implying.