A commodity is a good with a standardized fungible nature which is customarily bought, sold, and transported in bulk. Oil, copper, and corn are typical commodities. Usually, there is little or no information available about the origin of products sold or purchased as commodities although conditions of production or sale may be regulated.
You can contract to buy a commodity such as corn for delivery in the future. The commodity trader contracting with you may not own a farm, a grain elevator, or, indeed, any corn at the time they contract with you. However, there is an established futures market where they can obtain the corn from those who do.
It is in the terms of contracts for purchase or delivery of commodities that requirements for ethical production and proof of it may be specified. For, example, it is possible to contract for certified organic corn.