---
kind: "unit"
title: "37"
title_heading: "Patents, Trademarks, and Copyrights"
key: "chI/subchA/part41"
level: "part"
label: "Part 41"
heading: "Practice Before the Patent Trial and Appeal Board"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/37/chI-subchA-part41"
sections_count: 75
---

# Part 41 — Practice Before the Patent Trial and Appeal Board

Title 37 C.F.R. — Patents, Trademarks, and Copyrights › Chapter I — United States Patent and Trademark Office, Department of Commerce › Subchapter A — General

## Contents

- [Subpart A — General Provisions](/cfr/37/chI-subchA-part41-subpartA.md)
- [Subpart B — Ex Parte Appeals](/cfr/37/chI-subchA-part41-subpartB.md)
- [Subpart C — Inter Partes Appeals](/cfr/37/chI-subchA-part41-subpartC.md)
- [Subpart D — Contested Cases](/cfr/37/chI-subchA-part41-subpartD.md)
- [Subpart E — Patent Interferences](/cfr/37/chI-subchA-part41-subpartE.md)