Can extensions of time be granted after the Notice of Allowance?
Generally, extensions of time are not available after the Notice of Allowance has been issued. The MPEP clearly states:
The statutory (nonextendable) time period for payment of the issue fee is 3 months from the date of the Notice of Allowance (35 U.S.C. 151).
Furthermore, for any outstanding informalities at the time of allowance:
Extensions of time under 37 CFR 1.136(a) or (b) are NOT available to correct such informalities. Any such informalities must be corrected and the issue fee and the publication fee, if required, must be paid within the 3-month period.
This means that once you receive a Notice of Allowance, you have a strict 3-month period to pay the issue fee and correct any remaining issues. This period cannot be extended.
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