One of the hottest issues in the trade in plant products is patents. Until recently, patents were not given for living organisms, although varieties resulting from plant-breeding did enjoy similar protection.
Following changes in patent laws in the 1980s, there has been a flood of patents, either of particular varieities, or of uses. Many of these appear to represent attempts to patent uses that are already known. However, local uses are not always written down, and not always easily accessible to patent examiners. The validity of many patents has been questioned, and some have been revoked by patent offices. Well-known controversies include neem as an insecticide, turmermic, and Basmati rice.