Is there an additional fee for correcting inventorship after an Office action?

Yes, there is an additional fee for correcting inventorship after an Office action has been issued or mailed. According to 37 CFR 1.48(c):

Any request to correct or change the inventorship under paragraph (a) of this section filed after the Office action on the merits has been given or mailed in the application must also be accompanied by the fee set forth in § 1.17(d), unless the request is accompanied by a statement that the request to correct or change the inventorship is due solely to the cancelation of claims in the application.

This means that in addition to the processing fee required for all inventorship correction requests, an extra fee is required if the request is filed after an Office action, unless the change is due to claim cancellation.

To learn more:

• inventorship correction
• Office action
• additional fee
• claim cancellation