Can there be joint inventors for a plant patent?

Yes, plant patent applications can have joint inventors. This is explicitly stated in MPEP 1604:

In an application for a plant patent, there can be joint inventors.

This statement is supported by the case Ex parte Kluis, 70 USPQ 165 (Bd. App. 1945), which established this precedent.

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Tags: ex parte kluis, joint inventors, Multiple Inventors, Plant Patent