How does unity of invention differ from restriction practice?
Unity of invention and restriction practice are distinct concepts applied to different types of patent applications:
- Unity of invention applies to international applications (both Chapter I and II) and national stage applications submitted under 35 U.S.C. 371.
- Restriction practice, as outlined in 37 CFR 1.141 – 1.146, applies to U.S. national applications filed under 35 U.S.C. 111(a).
The MPEP states: “Examiners are reminded that unity of invention (not restriction practice pursuant to 37 CFR 1.141 – 1.146) is applicable in international applications (both Chapter I and II) and in national stage applications submitted under 35 U.S.C. 371.”
It’s important to note that restriction practice still applies to U.S. national applications filed under 35 U.S.C. 111(a), even if they claim benefit to an earlier international application or national stage application.
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