At what stage of patent prosecution can a restriction requirement be issued?
According to MPEP 811.02, a restriction requirement can be issued at any stage of patent prosecution up to final action. The section states:
“Since 37 CFR 1.142(a) provides that restriction is proper at any stage of prosecution up to final action, a second requirement may be made when it becomes proper, even though there was a prior requirement with which applicant complied.”
This means that patent examiners have the flexibility to issue restriction requirements throughout the examination process, from the initial review of the application up until a final office action is issued. This allows examiners to address issues of unity of invention or distinctness that may become apparent as the examination progresses.
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