When the PTAB remands a case to the examiner, which reason is NOT considered proper?

The reason for the correct answer revolves around the procedural limits set for the Patent Trial and Appeal Board (PTAB) when remanding cases. In the context of patent examinations, once a final rejection has been made by the examiner, the options available for further consideration by the applicant become limited.

When the PTAB remands a case, it must stay within the constraints of its authority and the procedural rules governing patent appeals. Allowing the examiner to consider an affidavit filed after a final rejection contravenes these procedural limits. Such affidavits or new evidence generally cannot be introduced at that late stage without specific legal basis or allowance, as the examination process is expected to have been completed prior to the appeal.

On the other hand, asking for a clearer explanation of the relevance of the references, selecting a preferred ground of rejection from multiple options, or preparing a supplemental examiner's answer are all considered proper reasons for remanding. These actions are in line with the PTAB's role to ensure that the case is fully and fairly adjudicated, allowing for clarification, refinement of arguments or rejections, and appropriate responses to the issues raised in the appeal. Thus, the involvement of new evidence post-final rejection is what distinguishes the correct reason for improper remand in