What is the difference between 37 CFR 1.136(a) and 37 CFR 1.136(b) extensions for appeal briefs?

The key difference between 37 CFR 1.136(a) and 37 CFR 1.136(b) extensions for appeal briefs lies in their applicability and requirements:

• 37 CFR 1.136(a): Not applicable to appeal brief filing deadlines.
• 37 CFR 1.136(b): Applicable to appeal brief filing deadlines, but requires showing of sufficient cause.

According to MPEP 1205.01:

“Extensions of time under 37 CFR 1.136(a) for patent applications are not applicable to the time period set in 37 CFR 41.37(a) for filing an appeal brief. See 37 CFR 1.136(b). However, an extension of time under 37 CFR 1.136(b) may be granted for filing an appeal brief after the time period set in 37 CFR 41.37(a).”

When seeking an extension for filing an appeal brief, you must use 37 CFR 1.136(b) and demonstrate sufficient cause for the extension.

To learn more:

• appeal brief
• extension types
• 37 CFR 1.136(a)
• 37 CFR 1.136(b)
• patent application