Can a joint inventor sign an amendment without power of attorney from the other inventor?
No, a joint inventor cannot sign an amendment without proper authorization from the other inventor(s). The MPEP 714.01(a) provides an example of this situation:
This applies, for instance, where the amendment is signed by only one of two joint inventors and the one signing has not been given a power of attorney by the other inventor.
In such cases, the amendment is considered improperly signed and will not be entered into the application. To properly prosecute the application, either all joint inventors must sign the amendment, or the signing inventor must have been granted power of attorney by the other inventor(s).
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