What are transitional applications under 37 CFR 1.129?

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.

Transitional applications are those filed on or before June 8, 1995, with an effective U.S. filing date of June 8, 1992, or earlier. These applications are subject to special provisions under 37 CFR 1.129, which allows for examination of more than one independent and distinct invention in certain cases.

According to the MPEP, “37 CFR 1.129(b)(1) provides for examination of more than one independent and distinct invention in certain applications pending for 3 years or longer as of June 8, 1995, taking into account any reference to any earlier application under 35 U.S.C. 120, 121, or 365(c).” This provision aims to address long-pending applications and provides applicants with options for pursuing multiple inventions in a single application.