MPEP § 804.01 — Prohibition of Nonstatutory Double Patenting Rejections Under 35 U.S.C. 121 (Annotated Rules)

§804.01 Prohibition of Nonstatutory Double Patenting Rejections Under 35 U.S.C. 121

USPTO MPEP version: BlueIron's Update: 2026-01-17

This page consolidates and annotates all enforceable requirements under MPEP § 804.01, including statutory authority, regulatory rules, examiner guidance, and practice notes. It is provided as guidance, with links to the ground truth sources. This is information only, it is not legal advice.

Prohibition of Nonstatutory Double Patenting Rejections Under 35 U.S.C. 121

This section addresses Prohibition of Nonstatutory Double Patenting Rejections Under 35 U.S.C. 121. Primary authority: 35 U.S.C. 121 and 37 CFR 121. Contains: 20 requirements and 1 prohibition.

Key Rules

Topic

Restriction Requirement (MPEP 802-803)

16 rules
StatutoryInformativeAlways
[mpep-804-01-426d4b93eb55a3af17d7e197]
Restriction Requirement for Same Invention in Different Claims
Note:
The rule requires examiners to be cautious about issuing restriction requirements when claims define the same invention differently, as this could lead to multiple patents for one invention.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Maintenance Fee Payment
StatutoryPermittedAlways
[mpep-804-01-6f36608a06f4fb817a4e9dcb]
Prolonged Patent Protection on Obvious Variants
Note:
If an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and extend protection beyond the statutory term for obvious variants of the same invention.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Obviousness
StatutoryInformativeAlways
[mpep-804-01-7c7914b9adecabdd76e404d1]
Divisional Applications Immune to Nonstatutory Double Patenting Rejections
Note:
This rule states that divisional applications restricted under § 121 are immune from nonstatutory double patenting rejections, preventing the issuance of multiple patents for essentially the same invention.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Maintenance Fee Payment
StatutoryInformativeAlways
[mpep-804-01-10ca7f2cea80f2e9f62a9f91]
Nonstatutory Double Patenting Rejections Prohibited for Divisional Applications
Note:
This rule prohibits nonstatutory double patenting rejections for claims in divisional applications that define the same invention, ensuring no prolongation of patent protection beyond the statutory term.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Maintenance Fee Payment
StatutoryProhibitedAlways
[mpep-804-01-56ec2efd83df5cfd40699b89]
Restriction Requirement Does Not Lead to Double Patenting
Note:
When multiple patents result from PTO restriction requirements, Section 121 protects the inventor from double patenting charges.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Maintenance Fee PaymentRestriction and Election Practice (MPEP Chapter 800)
StatutoryInformativeAlways
[mpep-804-01-cfdb9ec71266951b739e6052]
Nonstatutory Double Patenting Rejections Prohibited in Divisionals
Note:
Examiners cannot reject divisional applications under nonstatutory double patenting, as doing so may lead to multiple patents for the same invention beyond the statutory term.

This apparent nullification of nonstatutory double patenting as a ground of rejection or invalidity in divisional applications imposes a heavy burden on the Office to guard against erroneous requirements for restrictions where the claims define essentially the same invention in different language and where acquiescence to the restriction requirement might result in the issuance of several patents for the same invention. “[I]f an examiner issues a restriction requirement between patentably indistinct claims, two patents may issue and prolong patent protection beyond the statutory term on obvious variants of the same invention. This prolongation would occur because § 121 would immunize the restricted application against nonstatutory double patenting rejections.” Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003). “[W]hen the existence of multiple patents is due to the administrative requirements imposed by the Patent and Trademark Office, 35 U.S.C. Section 121 provides that the inventor shall not be prejudiced by having complied with those requirements. Thus when two or more patents result from a PTO restriction requirement, whereby aspects of the original application must be divided into separate applications, Section 121 insulates the ensuing patents from the charge of double patenting.” Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996) (citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)).

Jump to MPEP Source · 37 CFR 121Restriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Maintenance Fee Payment
StatutoryRequiredAlways
[mpep-804-01-65c741cc45287b07ab48b80d]
Requirement for Claims to Same Invention
Note:
Claims in the second application must be directed to the identical subject matter as those in the first application or patent.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(F) The claims of the second application are drawn to the “same invention” as the first application or patent.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Patent Eligibility
StatutoryRecommendedAlways
[mpep-804-01-3814bbeb613dc0f9ba549eec]
Statutory Double Patenting Rejection Under 35 U.S.C. 101 Not Subject to 35 U.S.C. 121 Prohibition
Note:
A statutory double patenting rejection under 35 U.S.C. 101 is required even if the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 applies.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 228 USPQ 837 (Fed. Cir. 1986) A statutory double patenting rejection under 35 U.S.C. 101 should be made, thus it is not necessary to determine whether the 35 U.S.C. 121 prohibition against making double patenting rejections is applicable.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Patent Eligibility
StatutoryRequiredAlways
[mpep-804-01-82dea4455b4fdba70af323ff]
Requirement for Identical Subject Matter
Note:
Claims of the second application must be identical to those of the first application to avoid nonstatutory double patenting rejections under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

“Same invention” means identical subject matter.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Patent Eligibility
StatutoryRequiredAlways
[mpep-804-01-983dd52b0a27804775f849ed]
Requirement for Claims to Same Invention Not Subject to Nonstatutory Double Patenting
Note:
This rule states that claims in a second application must be identical to those in the first application or patent to avoid nonstatutory double patenting rejections under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

See, e.g., Miller v. Eagle Mfg. Co., 151 U.S. 186 (1894); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Ockert, 245 F.2d 467, 114 USPQ 330 (CCPA 1957).

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Patent Eligibility
StatutoryRequiredAlways
[mpep-804-01-45342fb32ee4221ec32f9339]
Statutory Double Patenting Rejection for Same Invention Not Prohibited by 35 U.S.C. 121
Note:
This rule allows statutory double patenting rejections under 35 U.S.C. 101 for claims to the same invention, even if nonstatutory double patenting rejections would typically be prohibited under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

The 35 U.S.C. 121 prohibition against certain nonstatutory double patenting rejections does not apply to statutory double patenting rejections under 35 U.S.C. 101 of claims to the “same invention.”

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)Patent Eligibility
StatutoryRecommendedAlways
[mpep-804-01-74551756fb03f9c909518cd0]
Withdraw Restriction Between Elected Product and Process Claims
Note:
When process claims are rejoined, the restriction requirement between the elected product and these process claims must be withdrawn according to 37 CFR 1.141(b) and MPEP § 821.04.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

In this situation if any process claims are rejoined, the restriction requirement between the elected product and any rejoined process should be withdrawn in accordance with 37 CFR 1.141(b) and MPEP § 821.04.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-c0b28dcb8e0a4523291376e7]
CIP Application Including Restricted Claims Not Prohibited by Nonstatutory Double Patenting
Note:
A continuation-in-part (CIP) application that includes claims restricted from the original application is not subject to nonstatutory double patenting rejections under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(H) The second application is a continuation-in-part (CIP) application that includes claims restricted from the original application.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-771309a2dce7a9f3afca1629]
CIP Application Adds Unrestricted Matter
Note:
A CIP application, filed by a common inventor during the lifetime of an earlier application, must include new matter not previously disclosed in that earlier application.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

A CIP, by definition, is an application filed during the lifetime of an earlier application by at least one common (joint) inventor that repeats some substantial portion or all of the earlier application and adds matter not disclosed in the earlier application, i.e., the application in which the restriction requirement was originally made.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-3285e4a58c4cf7ab3fbf6685]
CIP Applications Do Not Qualify for U.S.C. 121 Protection
Note:
This rule states that divisional and original applications are protected under 35 U.S.C. 121, but continuation-in-part (CIP) applications do not qualify.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

35 U.S.C. 121 refers specifically and only to divisional and original applications, and does not afford protection to CIP applications.

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-84603dcae64e7e8ccc2e3e96]
CIP Application Claims Not Subject to Nonstatutory Double Patenting
Note:
CIP application claims that are restricted from the original application are not subject to nonstatutory double patenting rejections under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-08 (Fed. Cir. 2008) See also In re Janssen Biotech, Inc., 880 F.3d 1315, 1322,125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018) and G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015).

Jump to MPEP SourceRestriction Requirement (MPEP 802-803)Restriction and Election Practice (MPEP Chapter 800)
Topic

Safe Harbor for Divisional

15 rules
StatutoryInformativeAlways
[mpep-804-01-872029fdf16af77279404030]
Safe Harbor for Divisional Applications Filed in Response to Restriction Requirement
Note:
This rule prohibits using a patent issued from an application with a restriction requirement as a reference against divisional applications filed in response to that requirement.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Reissue and Reexamination
StatutoryInformativeAlways
[mpep-804-01-de427064c59063bd0fc78609]
Safe Harbor for Divisional Applications Filed Before Patent Issuance
Note:
This rule prohibits using a patent issuing from an application with a restriction requirement as a reference in nonstatutory double patenting rejections against divisional applications filed before the patent issuance, if the divisional is filed due to such a requirement.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryInformativeAlways
[mpep-804-01-73c0c8a7aa7e18c7f608868c]
35 U.S.C. 121 Safe Harbor for Divisional Applications
Note:
The prohibition applies only when the Office has made a requirement for restriction on an application.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Reissue and Reexamination
StatutoryInformativeAlways
[mpep-804-01-509665737c58bef9ac7f69d7]
Protection of Section 121 Limited to Divisionals
Note:
The protection under section 121 is limited to divisional applications filed as a result of a restriction requirement, not all types of continuing applications.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Reissue and Reexamination
StatutoryProhibitedAlways
[mpep-804-01-aa066469696368184c48c183]
Cannot Retroactively Restrict CIP as Divisional for Safe Harbor
Note:
A patentee cannot amend a continuation-in-part application to only parent application subject matter and redesignate it as a divisional to regain the safe harbor protection against nonstatutory double patenting.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-e8f3e94994f28b238c23dc17]
Safe Harbor for Divisional Applications Where Nonstatutory Double Patenting Does Not Apply
Note:
This rule outlines situations where nonstatutory double patenting rejections under 35 U.S.C. 121 do not apply to divisional applications.
The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:
  • (A) The applicant voluntarily files two or more applications without a restriction requirement by the examiner. In order to obtain the benefit of 35 U.S.C. 121, claims must be formally entered, restricted in, and removed from an earlier application before they are filed in a divisional application. Geneva Pharms. Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1870 (Fed. Cir. 2003) (For claims that were not in the original application and are first formally entered in a later divisional application, 35 U.S.C. 121 “does not suggest that the original application merely needs to provide some support for claims that are first entered formally in the later divisional application.” Id.); In re Schneller, 397 F.2d 350, 158 USPQ 210 (CCPA 1968).
  • (B) The claims of the application under examination and claims of the other application/patent are not consonant with the restriction requirement made by the examiner, since the claims have been changed in material respects from the claims at the time the requirement was made. For example, the divisional application filed includes additional claims not consonant in scope with the original claims subject to restriction in the parent. Symbol Technologies, Inc. v. Opticon, Inc., 935 F.2d 1569, 19 USPQ2d 1241 (Fed. Cir. 1991); Gerber Garment Technology, Inc. v. Lectra Systems, Inc., 916 F.2d 683, 16 USPQ2d 1436 (Fed. Cir. 1990). In order for consonance to exist, the line of demarcation between the independent and distinct inventions identified by the examiner in the requirement for restriction must be maintained. 916 F.2d at 688, 16 USPQ2d at 1440.
  • (C) The restriction requirement was withdrawn because the requirement was written in a manner which made it clear to applicant that the requirement was made subject to the nonallowance of generic or other linking claims and such generic or linking claims are subsequently allowed.
  • (D) The requirement for restriction (holding of lack of unity of invention) was only made in an international application by the International Searching Authority or the International Preliminary Examining Authority. However, the prohibition against nonstatutory double patenting rejections does apply to requirements for restriction (lack of unity of invention holdings) made in national stage applications submitted under 35 U.S.C. 371.
  • (E) The requirement for restriction was withdrawn, in its entirety or in pertinent part, by the examiner before the patent issues. With the withdrawal of the restriction requirement, the non-elected claims that are no longer withdrawn from consideration become subject to examination. “The restriction requirement disappears; it is as though it had not been made. With the disappearance of the restriction requirement, the need for a divisional application and the need for the [double patenting] prohibition also disappear.” In re Ziegler, 443 F.2d 1211, 1215, 170 USPQ 129, 132 (CCPA 1971). Note that a restriction requirement in an earlier-filed application does not carry over to claims of a continuation application in which the examiner does not reinstate or refer to the restriction requirement in the parent application. Reliance on a patent issued from such a continuation application to reject claims in a later-filed divisional application is not prohibited under 35 U.S.C. 121. Bristol-Myers Squibb Co. v. Pharmachemie BV, 361 F.3d 1343, 1348, 70 USPQ2d 1097, 1100 (Fed. Cir. 2004).
  • (F) The claims of the second application are drawn to the “same invention” as the first application or patent. Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 228 USPQ 837 (Fed. Cir. 1986). A statutory double patenting rejection under 35 U.S.C. 101 should be made, thus it is not necessary to determine whether the 35 U.S.C. 121 prohibition against making double patenting rejections is applicable. “Same invention” means identical subject matter. See, e.g., Miller v. Eagle Mfg. Co., 151 U.S. 186 (1894); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Ockert, 245 F.2d 467, 114 USPQ 330 (CCPA 1957). The 35 U.S.C. 121 prohibition against certain nonstatutory double patenting rejections does not apply to statutory double patenting rejections under 35 U.S.C. 101 of claims to the “same invention.”
  • (G) Where a requirement for restriction between a product, a process of making the product, and a process of using the product was made subject to the non-allowance of the product and the product is subsequently allowed. In this situation if any process claims are rejoined, the restriction requirement between the elected product and any rejoined process should be withdrawn in accordance with 37 CFR 1.141(b) and MPEP § 821.04.
  • (H) The second application is a continuation-in-part (CIP) application that includes claims restricted from the original application. A CIP, by definition, is an application filed during the lifetime of an earlier application by at least one common (joint) inventor that repeats some substantial portion or all of the earlier application and adds matter not disclosed in the earlier application, i.e., the application in which the restriction requirement was originally made. 35 U.S.C. 121 refers specifically and only to divisional and original applications, and does not afford protection to CIP applications. Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-08 (Fed. Cir. 2008). See also In re Janssen Biotech, Inc., 880 F.3d 1315, 1322,125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018) and G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015).
Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Petition to Reinstate
StatutoryRequiredAlways
[mpep-804-01-c265a51b472e7ad123abd397]
Claims Must Be Formally Entered, Restricted, and Removed Before Divisional Filing
Note:
To obtain the benefit of 35 U.S.C. 121, claims must be formally entered, restricted in, and removed from an earlier application before they are filed in a divisional application.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply (A) The applicant voluntarily files two or more applications without a restriction requirement by the examiner. In order to obtain the benefit of 35 U.S.C. 121, claims must be formally entered, restricted in, and removed from an earlier application before they are filed in a divisional application. Geneva Pharms. Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1870 (Fed. Cir. 2003) (For claims that were not in the original application and are first formally entered in a later divisional application, 35 U.S.C. 121 “does not suggest that the original application merely needs to provide some support for claims that are first entered formally in the later divisional application.” Id.); In re Schneller, 397 F.2d 350, 158 USPQ 210 (CCPA 1968).

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StatutoryRequiredAlways
[mpep-804-01-31429c31d8d826f995cf700d]
Claims First Entered in Divisional Do Not Need Original Support
Note:
For claims first formally entered in a later divisional application, the original application does not need to provide support as long as they are restricted and removed before filing.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

Geneva Pharms. Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1870 (Fed. Cir. 2003) (For claims that were not in the original application and are first formally entered in a later divisional application, 35 U.S.C. 121 “does not suggest that the original application merely needs to provide some support for claims that are first entered formally in the later divisional application.” In re Schneller, 397 F.2d 350, 158 USPQ 210 (CCPA 1968).

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-2cb0bc733fccd29855731366]
Divisional Application Claims Must Conform to Restriction Requirement
Note:
The claims in a divisional application must align with the restriction requirement made on the parent application, as they have been materially altered from the original claims.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(B) The claims of the application under examination and claims of the other application/patent are not consonant with the restriction requirement made by the examiner, since the claims have been changed in material respects from the claims at the time the requirement was made.

Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Divisional Applications (MPEP 201.06)
StatutoryRequiredAlways
[mpep-804-01-0184b9da07addcba1eed612a]
Divisional Application Claims Not Consonant with Original
Note:
The prohibition against nonstatutory double patenting rejections does not apply if the divisional application includes claims that are not consistent with the original claims subject to restriction in the parent.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

For example, the divisional application filed includes additional claims not consonant in scope with the original claims subject to restriction in the parent.

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-942f69a5f95d56afe8768c8a]
Divisional Claims Not Consonant with Restriction Requirement
Note:
The prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply if the claims in a divisional application have been changed in material respects from those subject to restriction in the parent application.
Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-0612651c044786bdcef69224]
Line of Demarcation Must Be Maintained for Consonant Claims
Note:
The rule requires that the distinction between independent inventions identified by the examiner in a restriction requirement be preserved when claims are changed, ensuring consonance with the original claims.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

In order for consonance to exist, the line of demarcation between the independent and distinct inventions identified by the examiner in the requirement for restriction must be maintained.

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryRequiredAlways
[mpep-804-01-185f73643c91fbbae68845f6]
Divisional Claims Not Consonant with Restriction Requirement
Note:
This rule states that nonstatutory double patenting rejections do not apply if the divisional application's claims have been changed in material respects from those subject to restriction in the parent application.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

916 F.2d at 688, 16 USPQ2d at 1440.

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryInformativeAlways
[mpep-804-01-f35d05974d27f6dc4e896602]
Double Patenting Rejection Allowed for Identical Inventions in Divisional and Parent Applications
Note:
35 U.S.C. 121 does not prevent a double patenting rejection when identical inventions are claimed in both the divisional and parent applications where a restriction requirement was made.

35 U.S.C. 121 does not prevent a double patenting rejection when the identical invention is claimed in the divisional application and the application/patent in which a restriction requirement was made. While identical claims should not arise if appropriate care is exercised in defining the independent and distinct inventions in a restriction requirement, if they do, the Office will make the statutory (35 U.S.C. 101) double patenting rejection because the patentee is entitled only to a single patent for an invention. As expressed in Studiengesellschaft Kohle, 784 F.2d at 361, 228 USPQ at 844, (J. Newman, concurring), “ 35 U.S.C. 121 of course does not provide that multiple patents may be granted on the identical invention.”

Jump to MPEP SourceSafe Harbor for DivisionalDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)
StatutoryPermittedAlways
[mpep-804-01-37736d4b62eb4716531ef0d5]
Double Patenting Rejection for Identical Claims in Divisional Applications
Note:
The rule states that identical claims cannot be granted in multiple patents, even if a restriction requirement was made. A double patenting rejection is permissible when the same invention is claimed in both the divisional and parent applications.

35 U.S.C. 121 does not prevent a double patenting rejection when the identical invention is claimed in the divisional application and the application/patent in which a restriction requirement was made. While identical claims should not arise if appropriate care is exercised in defining the independent and distinct inventions in a restriction requirement, if they do, the Office will make the statutory (35 U.S.C. 101) double patenting rejection because the patentee is entitled only to a single patent for an invention. As expressed in Studiengesellschaft Kohle, 784 F.2d at 361, 228 USPQ at 844, (J. Newman, concurring), “ 35 U.S.C. 121 of course does not provide that multiple patents may be granted on the identical invention.”

Jump to MPEP SourceSafe Harbor for DivisionalRestriction and Election Practice (MPEP Chapter 800)Divisional Applications (MPEP 201.06)
Topic

Restriction and Election Practice (MPEP Chapter 800)

4 rules
StatutoryInformativeAlways
[mpep-804-01-8f6aaaab35448a0bc709fe80]
Nonstatutory Double Patenting Prohibition for Restriction Requirements
Note:
This rule prohibits nonstatutory double patenting when restriction requirements are made between independent or distinct inventions.

The prohibition against holdings of nonstatutory double patenting applies to requirements for restriction between independent or distinct inventions, such as the related subject matter treated in MPEP § 806.04 through § 806.05(j), namely, between a combination and a subcombination thereof, between subcombinations disclosed as usable together, between a process and an apparatus for its practice, between a process and a product made by such process and between an apparatus and a product made by such apparatus, etc., so long as the claims in each application are filed as a result of such requirement.

Jump to MPEP Source · 37 CFR 806.05(j)Restriction and Election Practice (MPEP Chapter 800)Restriction Requirement (MPEP 802-803)
StatutoryRequiredAlways
[mpep-804-01-0e5383a61db3711bf7c4da5c]
Requirement for Voluntarily Filed Applications Without Restriction
Note:
The rule requires that applications be voluntarily filed without a restriction requirement by the examiner to avoid nonstatutory double patenting rejections under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply (A) The applicant voluntarily files two or more applications without a restriction requirement by the examiner. In order to obtain the benefit of 35 U.S.C. 121, claims must be formally entered, restricted in, and removed from an earlier application before they are filed in a divisional application. Geneva Pharms. Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1870 (Fed. Cir. 2003) (For claims that were not in the original application and are first formally entered in a later divisional application, 35 U.S.C. 121 “does not suggest that the original application merely needs to provide some support for claims that are first entered formally in the later divisional application.” Id.); In re Schneller, 397 F.2d 350, 158 USPQ 210 (CCPA 1968).

Jump to MPEP SourceRestriction and Election Practice (MPEP Chapter 800)Safe Harbor for DivisionalDivisional Applications (MPEP 201.06)
StatutoryRequiredAlways
[mpep-804-01-b6bd2c3ff62a1b3af7926dfe]
Requirement for Product Restriction When Process Claims Rejoined
Note:
When a product restriction is made subject to non-allowance and the product is subsequently allowed, rejoined process claims require withdrawal of the restriction requirement.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(G) Where a requirement for restriction between a product, a process of making the product, and a process of using the product was made subject to the non-allowance of the product and the product is subsequently allowed.

Jump to MPEP SourceRestriction and Election Practice (MPEP Chapter 800)Restriction Requirement (MPEP 802-803)
StatutoryRecommendedAlways
[mpep-804-01-eb5f5e699a690cabdea2f98c]
Identical Claims Require Double Patenting Rejection
Note:
If identical claims arise despite appropriate care in defining independent inventions, the Office will reject based on statutory double patenting because a single patent is entitled to only one invention.

35 U.S.C. 121 does not prevent a double patenting rejection when the identical invention is claimed in the divisional application and the application/patent in which a restriction requirement was made. While identical claims should not arise if appropriate care is exercised in defining the independent and distinct inventions in a restriction requirement, if they do, the Office will make the statutory (35 U.S.C. 101) double patenting rejection because the patentee is entitled only to a single patent for an invention. As expressed in Studiengesellschaft Kohle, 784 F.2d at 361, 228 USPQ at 844, (J. Newman, concurring), “ 35 U.S.C. 121 of course does not provide that multiple patents may be granted on the identical invention.”

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Topic

Petition to Reinstate

3 rules
StatutoryRequiredAlways
[mpep-804-01-faaf4272cbea0fa7ae30259c]
Requirement for Restriction Withdrawal Before Issuance
Note:
The examiner must withdraw the restriction requirement before a patent issues, allowing all claims to be examined together.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(E) The requirement for restriction was withdrawn, in its entirety or in pertinent part, by the examiner before the patent issues.

Jump to MPEP SourcePetition to ReinstateSafe Harbor for DivisionalWithdrawn Claims
StatutoryProhibitedAlways
[mpep-804-01-73009da9b1b6feb3654044a4]
Restriction Requirement Does Not Carry Over to Continuation
Note:
A restriction requirement in an earlier-filed application does not apply to claims of a continuation application unless the examiner reinstates or refers to it. Reliance on a patent issued from such a continuation application cannot be used to reject claims in a later-filed divisional application under 35 U.S.C. 121.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

Note that a restriction requirement in an earlier-filed application does not carry over to claims of a continuation application in which the examiner does not reinstate or refer to the restriction requirement in the parent application. Reliance on a patent issued from such a continuation application to reject claims in a later-filed divisional application is not prohibited under 35 U.S.C. 121.

Jump to MPEP SourcePetition to ReinstateSafe Harbor for DivisionalPatent Reinstatement
StatutoryRequiredAlways
[mpep-804-01-1b0a32cafb557c34e066e4fe]
Requirement for Withdrawn Restriction
Note:
If the restriction requirement is withdrawn, non-elected claims become subject to examination and are no longer subject to nonstatutory double patenting rejections.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

Bristol-Myers Squibb Co. v. Pharmachemie BV, 361 F.3d 1343, 1348, 70 USPQ2d 1097, 1100 (Fed. Cir. 2004).

Jump to MPEP SourcePetition to ReinstateSafe Harbor for DivisionalWithdrawn Claims
Topic

Divisional Applications (MPEP 201.06)

2 rules
StatutoryInformativeAlways
[mpep-804-01-321064c1e41e26c17b0fabb5]
Divisional Application Not Resulting From Office Restriction Is Exempt
Note:
A divisional application filed voluntarily by the applicant is not subject to nonstatutory double patenting rejection based on a parent application that was not required to be restricted by the Office.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceDivisional Applications (MPEP 201.06)Reissue and ReexaminationSafe Harbor for Divisional
StatutoryRequiredAlways
[mpep-804-01-75bddbabea941b3901c6d65f]
Withdrawal of Restriction Requirement Eliminates Double Patenting Prohibition
Note:
When the restriction requirement is withdrawn, divisional applications and double patenting prohibitions are no longer necessary.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

With the disappearance of the restriction requirement, the need for a divisional application and the need for the [double patenting] prohibition also disappear.” In re Ziegler, 443 F.2d 1211, 1215, 170 USPQ 129, 132 (CCPA 1971).

Jump to MPEP SourceDivisional Applications (MPEP 201.06)Restriction and Election Practice (MPEP Chapter 800)Petition to Reinstate
Topic

Reissue and Reexamination

2 rules
StatutoryInformativeAlways
[mpep-804-01-ae3d97c2cd0980169af063a3]
Divisional Applications Not Covered by 35 U.S.C. 121 Safe Harbor
Note:
The protection of 35 U.S.C. 121 does not extend to divisional applications filed voluntarily, only those in response to an Office requirement for restriction.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceReissue and ReexaminationSafe Harbor for DivisionalConcurrent Reissue Proceedings
StatutoryProhibitedAlways
[mpep-804-01-8459818aebe0c6e6e3699be6]
Patent Owner Cannot Retroactively Amend to Claim Safe Harbor Protection in Reexamination
Note:
A patent owner cannot amend a patent during reexamination to claim safe harbor protection for claims not originally within its scope.

35 U.S.C. 121 authorizes the Director to restrict the claims in a patent application to a single invention when independent and distinct inventions are presented for examination. The third sentence of 35 U.S.C. 121 prohibits the use of a patent issuing on an application in which a requirement for restriction has been made, or on an application filed as a result of such a requirement, as a reference against any divisional application in a nonstatutory double patenting rejection, if the divisional application is filed before the issuance of the patent. The 35 U.S.C. 121 prohibition applies only where the Office has made a requirement for restriction. The prohibition does not apply where the divisional application was voluntarily filed by the applicant and not in response to an Office requirement for restriction. The U.S. Court of Appeals for the Federal Circuit has concluded that the protection of 35 U.S.C. 121 does not extend to all types of continuing applications, stating that “the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.” Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc., 518 F.3d 1353, 1362, 86 USPQ2d 1001, 1007-1008 (Fed. Cir. 2008). Note that a patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application. See In re Janssen Biotech, Inc., 880 F.3d 1315, 1322, 125 USPQ2d 1525, 1529-30 (Fed. Cir. 2018)(“[A] patent owner cannot retroactively bring its challenged patent within the scope of the safe-harbor provision by amendment in a reexamination proceeding.”); G.D. Searle LLC v. Lupin Pharm., Inc., 790 F.3d 1349, 1355, 115 USPQ2d 1326, 1330 (Fed. Cir. 2015)(“Simply deleting that new matter from the reissue patent does not retroactively alter the nature of the [] application.”).

Jump to MPEP SourceReissue and ReexaminationConcurrent Reissue ProceedingsReissue Patent Practice
Topic

Nationals and Residents

1 rules
StatutoryRequiredAlways
[mpep-804-01-25c6bf819b95f50b8328fb6c]
Requirement for Lack of Unity of Invention Holdings in National Stage
Note:
The prohibition against nonstatutory double patenting rejections does not apply to requirements for restriction (lack of unity of invention) made in national stage applications submitted under 35 U.S.C. 371, but applies when made by the International Searching Authority or the International Preliminary Examining Authority.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

(D) The requirement for restriction (holding of lack of unity of invention) was only made in an international application by the International Searching Authority or the International Preliminary Examining Authority. However, the prohibition against nonstatutory double patenting rejections does apply to requirements for restriction (lack of unity of invention holdings) made in national stage applications submitted under 35 U.S.C. 371.

Jump to MPEP SourceNationals and ResidentsReceiving Office (RO/US)International Searching Authority (ISA)
Topic

Withdrawn Claims

1 rules
StatutoryRequiredAlways
[mpep-804-01-50e8d675b051f2109fcc2137]
Non-Elected Claims Subject to Examination After Withdrawal of Restriction Requirement
Note:
When the restriction requirement is withdrawn, non-elected claims that were previously excluded from consideration become subject to examination.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

With the withdrawal of the restriction requirement, the non-elected claims that are no longer withdrawn from consideration become subject to examination.

Jump to MPEP SourceWithdrawn ClaimsElection Requirement (MPEP 808, 818)Restriction and Election Practice (MPEP Chapter 800)
Topic

Intervening Rights After Reinstatement

1 rules
StatutoryRequiredAlways
[mpep-804-01-a52a8ea68e894b1b601640ad]
Requirement for Restriction Withdrawal Disappears
Note:
When the restriction requirement is withdrawn, nonstatutory double patenting rejections are no longer applicable.

The following are situations where the prohibition against nonstatutory double patenting rejections under 35 U.S.C. 121 does not apply:

“The restriction requirement disappears; it is as though it had not been made.

Jump to MPEP SourceIntervening Rights After ReinstatementRestriction and Election Practice (MPEP Chapter 800)Petition to Reinstate

Citations

Primary topicCitation
Restriction Requirement (MPEP 802-803)
Restriction and Election Practice (MPEP Chapter 800)
Safe Harbor for Divisional
35 U.S.C. § 101
Divisional Applications (MPEP 201.06)
Intervening Rights After Reinstatement
Nationals and Residents
Petition to Reinstate
Reissue and Reexamination
Restriction Requirement (MPEP 802-803)
Restriction and Election Practice (MPEP Chapter 800)
Safe Harbor for Divisional
Withdrawn Claims
35 U.S.C. § 121
Nationals and Residents
Safe Harbor for Divisional
35 U.S.C. § 371
Restriction Requirement (MPEP 802-803)
Restriction and Election Practice (MPEP Chapter 800)
Safe Harbor for Divisional
37 CFR § 1.141(b)
Restriction and Election Practice (MPEP Chapter 800)37 CFR § 806.05(j)
Restriction and Election Practice (MPEP Chapter 800)MPEP § 806.04
Restriction Requirement (MPEP 802-803)
Restriction and Election Practice (MPEP Chapter 800)
Safe Harbor for Divisional
MPEP § 821.04
Restriction Requirement (MPEP 802-803)Applied Materials Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1568, 40 USPQ2d 1481, 1484 (Fed. Cir. 1996)
Divisional Applications (MPEP 201.06)
Intervening Rights After Reinstatement
Petition to Reinstate
Safe Harbor for Divisional
Withdrawn Claims
Bristol-Myers Squibb Co. v. Pharmachemie BV, 361 F.3d 1343, 1348, 70 USPQ2d 1097, 1100 (Fed. Cir. 2004)
Restriction Requirement (MPEP 802-803)Geneva Pharmaceuticals Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373, 1379, 68 USPQ2d 1865, 1869 (Fed. Cir. 2003)
Safe Harbor for DivisionalGerber Garment Technology, Inc. v. Lectra Systems, Inc., 916 F.2d 683, 16 USPQ2d 1436 (Fed. Cir. 1990)
Restriction Requirement (MPEP 802-803)
Safe Harbor for Divisional
In re Ockert, 245 F.2d 467, 114 USPQ 330 (CCPA 1957)
Restriction and Election Practice (MPEP Chapter 800)
Safe Harbor for Divisional
In re Schneller, 397 F.2d 350, 158 USPQ 210 (CCPA 1968)
Restriction Requirement (MPEP 802-803)
Safe Harbor for Divisional
In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970)
Divisional Applications (MPEP 201.06)
Intervening Rights After Reinstatement
Petition to Reinstate
Safe Harbor for Divisional
Withdrawn Claims
In re Ziegler, 443 F.2d 1211, 1215, 170 USPQ 129, 132 (CCPA 1971)
Restriction Requirement (MPEP 802-803)
Safe Harbor for Divisional
Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 228 USPQ 837 (Fed. Cir. 1986)
Safe Harbor for DivisionalSymbol Technologies, Inc. v. Opticon, Inc., 935 F.2d 1569, 19 USPQ2d 1241 (Fed. Cir. 1991)
Restriction Requirement (MPEP 802-803)citing Studiengesellschaft Kohle mbH v. Northern Petrochemical Co., 784 F.2d 351, 354, 228 USPQ 837, 840 (Fed. Cir. 1986)

Source Text from USPTO’s MPEP

This is an exact copy of the MPEP from the USPTO. It is here for your reference to see the section in context.

BlueIron Last Updated: 2026-01-17