Genus
Robinia
2 US plant patents have been granted in this genus. 2 are already in the public domain — anyone may propagate and sell them.
Already in the public domain — 2 cultivars
Most recently freed first. Anyone may propagate and sell these plants — though the name it is sold under may still be a live trademark.
- Lace LadyPP9771Robinia plant named `Lace Lady`PUBLIC DOMAINApril 25, 2015
- Purple CrownPP7731Robinia `Purple Crown`PUBLIC DOMAINMay 7, 2010
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.