How does the USPTO evaluate “sufficient cause” for time extensions in inter partes reexamination?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The USPTO evaluates “sufficient cause” for time extensions in inter partes reexamination by balancing two factors:

1. Providing the patent owner a fair opportunity to respond
2. Adhering to the statutory requirement for special dispatch (35 U.S.C. 314(c))

The MPEP states: “Evaluation of whether “sufficient cause” has been shown for an extension must be made by balancing the desire to provide the patent owner with a fair opportunity to respond, against the requirement of the statute, 35 U.S.C. 314(c), that the proceedings be conducted with special dispatch.“

Requests must include:

• A statement of actions taken to provide a response
• An explanation of why additional time is needed
• A factual accounting of reasonably diligent behavior by all responsible parties