What are the time limits for suggesting an interference in a patent application?

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.

The time limits for suggesting an interference in a patent application are specified in 37 CFR 41.202(c). According to MPEP 2304.02:

“The suggestion of interference must be made within the time specified in 37 CFR 41.202(c).”

The time limits are as follows:

• For an application not subject to pre-grant publication: prior to six months from the date of allowance.
• For an application subject to pre-grant publication: prior to six months from the date of publication of the application or prior to three months from the date of allowance, whichever is later.

It’s important to note that these time limits are strictly enforced, and suggestions of interference filed outside these timeframes may not be considered.