No patented or GMO plants are allowed at our exchanges. You can look up any plant by Googling its name +patent. We support the farmers and hybridizers. Not too many fruits are GMO ….yet (besides HoneySweet plums, Rainbow Papaya, Italian Gala Apples, and Okanagan apples), but plenty are patented.
Note that patents expire after an initial period of protection, but trademarks do not. From goodfruit.com: “Trademarks allow those involved with a patented product to develop a brand for a new variety and exclude others using the trademarked name. For example, Pink Lady is the trademarked name for Cripps Pink cultivar. Only those growers and shippers participating in the Pink Lady America program can use the Pink Lady name and flowing heart logo.”
Patents can be found here: http://patft.uspto.gov/netahtml/PTO/search-adv.htm
Trademarks can be found here: http://tess2.uspto.gov/bin/gate.exe?f=tess&state=4809:gphuhy.1.1
Trademarked plant names are often confuse the original name of a plant variety, just being used for marketing the same variety with a more appealing name with which to sell them. Here is a short article on the subject from a commercial nursery: http://www.lazyssfarm.com/Inquiring%20Minds/trademarked_plants.htm
If you want to delve into trademark name confusion more deeply, see this more comprehensive review of the situation from an opinionated nurseryperson’s perspective: http://www.plantdelights.com/Article-Trademarks-in-Horticulture