# MPEP § 803: Restriction — When Proper

> Federal · Agency guidance · In force

URL: https://www.frixlaw.com/law-library/statutes/MPEP_S803

## Section

- **Citation:** MPEP § 803
- **Heading:** Restriction — When Proper
- **Jurisdiction:** Federal
- **Kind:** Agency guidance
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** USPTO MPEP / Chapter 0800 - Restriction in Applications Filed Under 35 U.S.C. 111 › Double Patenting / MPEP § 803

## Text

Under the statute, the claims of an application may properly be required to
be restricted to one of two or more claimed inventions only if they are able to support
separate patents and they are either independent (
MPEP § 802.01
,
§ 806.06
, and
§ 808.01
) or distinct (
MPEP § 806.05
-
§ 806.05(j)
).
If the search and examination of all the claims in an application can be
made without serious burden, the examiner must examine them on the merits, even though they
include claims to independent or distinct inventions.
I.
CRITERIA FOR RESTRICTION BETWEEN PATENTABLY DISTINCT INVENTIONS
There are two criteria for a proper requirement for restriction between
patentably distinct inventions:
(A) The inventions must be independent (see
MPEP § 802.01
,
§
806.06
,
§ 808.01
) or distinct as claimed
(see
MPEP §
806.05
-
§ 806.05(j)
); and
(B) There would be a serious search and/or examination burden on the
examiner if restriction is not required (see
MPEP § 803.02
,
§ 808
, and
§ 808.02
).
II.
GUIDELINES
Examiners must provide reasons and/or examples to support conclusions,
but need not cite documents to support the restriction requirement in most cases.
Where plural inventions are capable of being viewed as related in two
ways, both applicable criteria for distinctness must be demonstrated to support a
restriction requirement.
If there is an express admission that the claimed inventions would have
been obvious over each other within the meaning of
35 U.S.C. 103
, restriction should
not be required.
In re Lee,
199 USPQ 108 (Comm’r Pat. 1978).
For purposes of the initial requirement, a serious search burden on the
examiner may be
prima facie
shown by appropriate explanation of
separate classification, or separate status in the art, or a different field of search
as defined in
MPEP
§ 808.02
. Similarly, a serious examination burden, for
example, may be
prima facie
shown by appropriate explanation of
non-prior art issues under
35 U.S.C. 101
,
pre-AIA 35 U.S.C.
112
, first paragraph, and/or
35 U.S.C
den on the
examiner may be
prima facie
shown by appropriate explanation of
separate classification, or separate status in the art, or a different field of search
as defined in
MPEP
§ 808.02
. Similarly, a serious examination burden, for
example, may be
prima facie
shown by appropriate explanation of
non-prior art issues under
35 U.S.C. 101
,
pre-AIA 35 U.S.C.
112
, first paragraph, and/or
35 U.S.C.
112(a)
relevant to one invention that are not relevant to the
other invention. A
prima facie
showing of serious search and/or
examination burden may be rebutted by appropriate showings or evidence by the applicant.
Insofar as the criteria for restriction practice relating to Markush claims is
concerned, the criteria is set forth in
MPEP § 803.02
. Insofar as the criteria
for restriction or election practice relating to claims to genus-species, see
MPEP
§ 806.04
-
§ 806.04(i)
and
§ 808.01(a)
.

## Nearby sections

- [MPEP § 801 Introduction](https://www.frixlaw.com/law-library/statutes/MPEP_S801.md)
- [MPEP § 802 Basis for Restriction Practice in Statute and Rules](https://www.frixlaw.com/law-library/statutes/MPEP_S802.md)
- [MPEP § 802.01 Meaning of “Independent” and “Distinct”](https://www.frixlaw.com/law-library/statutes/MPEP_S802.01.md)
- [MPEP § 802.02 Definition of Restriction](https://www.frixlaw.com/law-library/statutes/MPEP_S802.02.md)
- [MPEP § 803 Restriction — When Proper](https://www.frixlaw.com/law-library/statutes/MPEP_S803.md)
- [MPEP § 803.01 Review by Examiner with at Least Partial Signatory Authority](https://www.frixlaw.com/law-library/statutes/MPEP_S803.01.md)
- [MPEP § 803.02 Election of Species Requirements – Markush Claims](https://www.frixlaw.com/law-library/statutes/MPEP_S803.02.md)
- [MPEP § 803.03 Transitional Applications](https://www.frixlaw.com/law-library/statutes/MPEP_S803.03.md)
- [MPEP § 803.03(a) Transitional Application — Linking Claim Allowable](https://www.frixlaw.com/law-library/statutes/MPEP_S803.03(a).md)
- [MPEP § 803.03(b) Transitional Application — Generic Claim Allowable](https://www.frixlaw.com/law-library/statutes/MPEP_S803.03(b).md)
- [MPEP § 803.04 Nucleotide Sequences](https://www.frixlaw.com/law-library/statutes/MPEP_S803.04.md)
- [MPEP § 803.05 Reissue Application Practice](https://www.frixlaw.com/law-library/statutes/MPEP_S803.05.md)
- [MPEP § 804 Definition of Double Patenting](https://www.frixlaw.com/law-library/statutes/MPEP_S804.md)
- [MPEP § 804.01 Prohibition of Nonstatutory Double Patenting Rejections Under 35 U.S.C. 121](https://www.frixlaw.com/law-library/statutes/MPEP_S804.01.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/MPEP_S803. Check the current official text before relying on it. Not legal advice.