35 U.S.C. § 21 — Filing date and day for taking (MPEP Coverage Index) – BlueIron IP

35 U.S.C. § 21 Filing date and day for taking

Source: Patent Statute (35 U.S.C.)BlueIron Update:

This page consolidates MPEP guidance interpreting 35 U.S.C. § 21, including 94 rules 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.

Summary

This section covers the calculation of the filing date for a U.S. nonprovisional patent application, where the first day is not counted and extensions are provided for holidays or weekends.

What this section covers

  • This section explains how to determine the filing date for a U.S. nonprovisional patent application by excluding the first day of the priority period.
  • It also covers how to handle situations where the filing date falls on a holiday or weekend, extending the deadline to the next business day.

Key obligations

  • The filing date is calculated by excluding the first day of the priority period, ensuring it starts from the next day.
  • Practitioners must ensure the filing date is correctly calculated, especially for international applications, to avoid missing critical deadlines.

Practice notes

  • Filing on a holiday or weekend extends the filing deadline to the next business day, but missing the original date can result in application abandonment.

Related Provisions

Based on MPEP Last Modified: 10/30/2024 08:50:22