What happens if the USPTO is closed on the priority deadline day?
If the USPTO is closed on the priority deadline day, the deadline is extended to the next business day when the office is open. This applies to both scheduled and unscheduled closings.
The MPEP states: When the entire U.S. Patent and Trademark Office is officially closed for business for an entire day, for reasons due to adverse weather or other causes, the Office will consider each such day a ‘Federal holiday within the District of Columbia’ under 35 U.S.C. 21. Any action or fee due on such a day may be taken, or fee paid, on the next succeeding business day the Office is open.
(MPEP 213.03)
However, it’s important to note that if the USPTO is open for any part of a business day, papers are due on that day even if the office closes early or opens late due to an unscheduled event.
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