Genus
Castanea
9 US plant patents have been granted in this genus. 1 is already in the public domain — anyone may propagate and sell it. The next of the 8 still protected comes off patent on January 30, 2028.
Still under patent — 8 cultivars
Soonest to come off patent first. You may not propagate these for sale until the date shown.
- AU EncorePP20336Chestnut plant named ‘AU Encore’UNDER PATENTJanuary 30, 2028
- AU Buck IIPP20337Chestnut plant named ‘AU Buck II’UNDER PATENTJanuary 30, 2028
- AU Gobbler IPP20338Chestnut plant named ‘AU Gobbler I’UNDER PATENTJanuary 30, 2028
- AU Buck IIIPP20381Chestnut plant named ‘AU Buck III’UNDER PATENTJanuary 30, 2028
- Au Gobbler IIPP20553Chestnut plant named ‘Au Gobbler II’UNDER PATENTJanuary 30, 2028
- AU PremierPP20587Chestnut plant named ‘AU Premier’UNDER PATENTJanuary 30, 2028
- Au Buck IPP20588Chestnut plant named ‘Au Buck I’UNDER PATENTJanuary 30, 2028
- AU BUCK IVPP20624Chestnut plant named ‘AU BUCK IV’UNDER PATENTJanuary 30, 2028
Already in the public domain — 1 cultivar
Most recently freed first. Anyone may propagate and sell this plant — though the name it is sold under may still be a live trademark.
- RevivalPP5537Hybrid chestnut tree `Revival`PUBLIC DOMAINNovember 4, 2003
A patent expiring frees the plant, and its cultivar name comes with it — cultivar names cannot be trademarked, so they are always free to use. What it does not free is any brand name the plant is marketed under. Those are trademarks and renew indefinitely.