MPEP § 1843.01 — Prior Art for Chapter I Processing (Annotated Rules)

§1843.01 Prior Art for Chapter I Processing

USPTO MPEP version: BlueIron's Update: 2025-12-31

This page consolidates and annotates all enforceable requirements under MPEP § 1843.01, 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.

Prior Art for Chapter I Processing

This section addresses Prior Art for Chapter I Processing. Contains: 5 requirements, 4 guidance statements, 3 permissions, and 7 other statements.

Key Rules

Topic

International Filing Date

5 rules
StatutoryRequiredAlways
[mpep-1843-01-58f8eb21d6ef280a124a16ae]
Relevant Prior Art Must Be Noted
Note:
Any published application or patent that would be relevant prior art if published before the international filing date must be specifically mentioned in the international search report.

(c) Any published application or any patent whose publication date is the same as, or later than, but whose filing date, or, where applicable, claimed priority date, is earlier than the international filing date of the international application searched, and which would constitute relevant prior art for the purposes of Article 15(2) had it been published prior to the international filing date, shall be specially mentioned in the international search report.

Jump to MPEP SourceInternational Filing DateInternational Searching Authority (ISA)International Search Report
StatutoryInformativeAlways
[mpep-1843-01-609204acbfd6d44b31f5b9fa]
Prior Art for International Application
Note:
Identifies everything publicly disclosed worldwide before filing date that can help determine if the invention is new and inventive.

The objective of the international search is to discover relevant prior art (PCT Article 15(2)). “Prior art” consists of everything which has been made available to the public anywhere in the world by means of written disclosure (including drawings and other illustrations); it is relevant in respect of the international application if it is capable of being of assistance in determining that the claimed invention is or is not new and that the claimed invention does or does not involve an inventive step (i.e., that it is or is not obvious), and if the making available to the public occurred prior to the international filing date for the purposes of the international search report and prior to the earliest validly claimed priority date for the purposes of the written opinion of the International Searching Authority. For further details, see PCT Rules 33, 43bis.1(b) and 64.

Jump to MPEP SourceInternational Filing DateInternational Searching Authority (ISA)International Search Report
StatutoryRecommendedAlways
[mpep-1843-01-541cbc082701ba694b7156a6]
Prior Art for Other Offices During Search
Note:
Examiners should identify and cite relevant prior art from other offices during the search, even if it shares applicants or inventors with the application under consideration.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceInternational Filing DateInternational Searching Authority (ISA)International Search Report
StatutoryInformativeAlways
[mpep-1843-01-77b89ee6bc8216142767b0d2]
International Filing Date Determines Prior Art Consideration
Note:
The international filing date or, where applicable, the priority date, determines which documents are considered prior art for the International Searching Authority's written opinion.

The relevant date for the purpose of considering prior art for the purposes of establishment of the written opinion of the International Searching Authority is defined in PCT Rule 64.1(b) as the international filing date or, where the international application contains a claim for priority, the date provided in PCT Rule 64.1(b)(ii) – (iii). See MPEP § 1878.01(a).

Jump to MPEP SourceInternational Filing DateInternational Searching Authority (ISA)International Search Report
StatutoryRecommendedAlways
[mpep-1843-01-552e455099040fcd584f2660]
Written Disclosure Required for Prior Art
Note:
A non-written disclosure is not considered prior art unless substantiated by a written disclosure available before the international filing date. However, if the written disclosure was made after the filing date, it must be noted in the search report.

A non-written disclosure such as an oral disclosure, use, exhibition or other means of disclosure is not relevant prior art for the purposes of the international search unless it is substantiated by a written disclosure made available to the public prior to the international filing date and it is the written disclosure which constitutes the prior art. However, if the date on which the written disclosure was made available to the public was on or after the filing date of the international application under consideration, the search report should separately mention that fact and the date on which the written disclosure was available, even though such a written disclosure does not meet the definition of relevant prior art in the international phase, so long as the non-written disclosure was made available to the public on a date prior to the international filing date since such a non-written disclosure may be considered to be prior art under national law in the national phase. See PCT Rules 33.1(b), 64.2 and 70.9.

Jump to MPEP SourceInternational Filing DateNationals and ResidentsReceiving Office (RO/US)
Topic

Article 19 Amendment Scope

5 rules
StatutoryInformativeAlways
[mpep-1843-01-3fd57d30c83c9b7304108d01]
Priority Claim Valid Within Two Months
Note:
The filing date of an earlier application is used if the international application claims priority and has a later filing date within two months after the priority period expired, unless the International Preliminary Examining Authority deems the claim invalid for other reasons.

(b) For the purposes of paragraph (a), the relevant date shall be:

(iii) where the international application under international preliminary examination claims the priority of an earlier application and has an international filing date which is later than the date on which the priority period expired but within the period of two months from that date, the filing date of such earlier application, unless the International Preliminary Examining Authority considers that the priority claim is not valid for reasons other than the fact that the international application has an international filing date which is later than the date on which the priority period expired.

Jump to MPEP SourceArticle 19 Amendment ScopeArticle 19 Amendment TimingPCT Claims Format
StatutoryInformativeAlways
[mpep-1843-01-ef3e94e3dc96f961a420d2b3]
Examiners Must Cite Relevant Prior Art
Note:
Examiners are required to cite prior art that may assist in determining if claims have sufficient support and industrial applicability.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceArticle 19 Amendment ScopePCT Description RequirementsInternational Search Report
StatutoryInformativeAlways
[mpep-1843-01-c9f75fac93d93995bd8345cc]
Examiner Must Consider Relevant Prior Art
Note:
The examiner is required to identify and cite relevant prior art, including documents that may cast doubt on priority claims or illustrate the technological background of the invention.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceArticle 19 Amendment ScopeArticle 19 Amendment TimingPCT Description Requirements
StatutoryInformativeAlways
[mpep-1843-01-95a808e8281086048550842c]
Examiner Must Not Expand Search Unless Special Reason
Note:
Examiners should not search for additional prior art unless there is a special reason in a particular case.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceArticle 19 Amendment ScopeArticle 19 Amendment TimingPCT Description Requirements
StatutoryRecommendedAlways
[mpep-1843-01-1b390772a5cda4e633b5ada0]
Claims Guide International Search Coverage
Note:
The international search must cover the entire subject matter of the claims, considering the description and drawings if present.

The international search is made on the basis of the claims, with due regard to the description and the drawings (if any) contained in the international application (PCT Article 15(3)) and should cover the entire subject matter to which the claims are directed or to which they might reasonably be expected to be directed after they have been amended (PCT Rule 33.3(b)).

Jump to MPEP SourceArticle 19 Amendment ScopePCT Description RequirementsInternational Searching Authority (ISA)
Topic

35 U.S.C. 102 – Novelty / Prior Art

5 rules
StatutoryInformativeAlways
[mpep-1843-01-f4f338e0248c987c7d92dbb0]
Internet and Online Database Disclosures Considered as Written Disclosure
Note:
Information disclosed on the internet or online databases is treated the same as other written disclosures for assessing novelty and inventive step.

Prior art disclosure on the Internet or on an online database is considered in the same manner as other forms of written disclosure. Information disclosed on the Internet or an online database is considered to be publicly available as of the date the disclosure was publicly posted. Where the examiner obtains an electronic document that establishes the publication date for the Internet disclosure, he/she should make a printout of this document, which must mention both the URL of the relevant Internet disclosure and the date of publication of that relevant Internet disclosure. The examiner must then cite this printout in the international search report as an “L” document and cite the relevant Internet disclosure according to the relevance of its content (“X”, “Y”, “A”) and according to the date as established (“X”, “Y”, “A”, “P,X”, “P,Y”, “P,A”, “E”, etc.). See MPEP § 1844.01, subsection VII. Where the examiner is unable to establish the publication date of the relevant Internet disclosure and it is relevant to the inventive step and/or novelty of the claimed invention, he/she should cite it in the international search report as a category “L” document for those claims which it would have affected if it were published in time, giving the date the document was printed out as its publication date.

Jump to MPEP SourceNovelty / Prior Art
StatutoryInformativeAlways
[mpep-1843-01-ebdd27c858cf50cfb694d221]
Internet Disclosure Considered Publicly Available Upon Posting
Note:
Information disclosed on the internet is deemed publicly available as of its posting date.

Prior art disclosure on the Internet or on an online database is considered in the same manner as other forms of written disclosure. Information disclosed on the Internet or an online database is considered to be publicly available as of the date the disclosure was publicly posted. Where the examiner obtains an electronic document that establishes the publication date for the Internet disclosure, he/she should make a printout of this document, which must mention both the URL of the relevant Internet disclosure and the date of publication of that relevant Internet disclosure. The examiner must then cite this printout in the international search report as an “L” document and cite the relevant Internet disclosure according to the relevance of its content (“X”, “Y”, “A”) and according to the date as established (“X”, “Y”, “A”, “P,X”, “P,Y”, “P,A”, “E”, etc.). See MPEP § 1844.01, subsection VII. Where the examiner is unable to establish the publication date of the relevant Internet disclosure and it is relevant to the inventive step and/or novelty of the claimed invention, he/she should cite it in the international search report as a category “L” document for those claims which it would have affected if it were published in time, giving the date the document was printed out as its publication date.

Jump to MPEP SourceNovelty / Prior Art
StatutoryRequiredAlways
[mpep-1843-01-5f38af5050b7c67fcc055fb6]
Examiner Must Print URL and Publication Date for Internet Disclosures
Note:
The examiner must print a document establishing the publication date of an internet disclosure, including the URL and publication date, and cite it in the international search report.

Prior art disclosure on the Internet or on an online database is considered in the same manner as other forms of written disclosure. Information disclosed on the Internet or an online database is considered to be publicly available as of the date the disclosure was publicly posted. Where the examiner obtains an electronic document that establishes the publication date for the Internet disclosure, he/she should make a printout of this document, which must mention both the URL of the relevant Internet disclosure and the date of publication of that relevant Internet disclosure. The examiner must then cite this printout in the international search report as an “L” document and cite the relevant Internet disclosure according to the relevance of its content (“X”, “Y”, “A”) and according to the date as established (“X”, “Y”, “A”, “P,X”, “P,Y”, “P,A”, “E”, etc.). See MPEP § 1844.01, subsection VII. Where the examiner is unable to establish the publication date of the relevant Internet disclosure and it is relevant to the inventive step and/or novelty of the claimed invention, he/she should cite it in the international search report as a category “L” document for those claims which it would have affected if it were published in time, giving the date the document was printed out as its publication date.

Jump to MPEP SourceNovelty / Prior Art
StatutoryRequiredAlways
[mpep-1843-01-1812bd457ca16c987944eed3]
Examiner Must Cite Internet Disclosures in Search Report
Note:
The examiner must print out and cite relevant internet disclosures as 'L' documents in the international search report, specifying their content relevance and publication date.

Prior art disclosure on the Internet or on an online database is considered in the same manner as other forms of written disclosure. Information disclosed on the Internet or an online database is considered to be publicly available as of the date the disclosure was publicly posted. Where the examiner obtains an electronic document that establishes the publication date for the Internet disclosure, he/she should make a printout of this document, which must mention both the URL of the relevant Internet disclosure and the date of publication of that relevant Internet disclosure. The examiner must then cite this printout in the international search report as an “L” document and cite the relevant Internet disclosure according to the relevance of its content (“X”, “Y”, “A”) and according to the date as established (“X”, “Y”, “A”, “P,X”, “P,Y”, “P,A”, “E”, etc.). See MPEP § 1844.01, subsection VII. Where the examiner is unable to establish the publication date of the relevant Internet disclosure and it is relevant to the inventive step and/or novelty of the claimed invention, he/she should cite it in the international search report as a category “L” document for those claims which it would have affected if it were published in time, giving the date the document was printed out as its publication date.

Jump to MPEP SourceNovelty / Prior Art
StatutoryRecommendedAlways
[mpep-1843-01-371ad86109670133fb6f2e17]
Publication Date for Uncertain Internet Disclosures
Note:
If the examiner cannot determine the publication date of an internet disclosure that affects inventive step or novelty, it should be cited as a category ‘L’ document with the printout date used as its publication date.

Prior art disclosure on the Internet or on an online database is considered in the same manner as other forms of written disclosure. Information disclosed on the Internet or an online database is considered to be publicly available as of the date the disclosure was publicly posted. Where the examiner obtains an electronic document that establishes the publication date for the Internet disclosure, he/she should make a printout of this document, which must mention both the URL of the relevant Internet disclosure and the date of publication of that relevant Internet disclosure. The examiner must then cite this printout in the international search report as an “L” document and cite the relevant Internet disclosure according to the relevance of its content (“X”, “Y”, “A”) and according to the date as established (“X”, “Y”, “A”, “P,X”, “P,Y”, “P,A”, “E”, etc.). See MPEP § 1844.01, subsection VII. Where the examiner is unable to establish the publication date of the relevant Internet disclosure and it is relevant to the inventive step and/or novelty of the claimed invention, he/she should cite it in the international search report as a category “L” document for those claims which it would have affected if it were published in time, giving the date the document was printed out as its publication date.

Jump to MPEP SourceNovelty / Prior Art
Topic

PCT International Application Filing

5 rules
StatutoryPermittedAlways
[mpep-1843-01-18d08fdc15dd92365ef5ca09]
Internet Search Must Use Secure Connection
Note:
When conducting the search, use secure connections for databases accessible via the internet to maintain confidentiality.

When conducting the search, it may be necessary to make use of the Internet as a search tool. Where the international application has not yet been published at the time of the search, there exists the danger that search terms used in the search on non-secure Internet search engines or in databases available on the Internet may be observed by third parties. Accordingly, all websites must be treated as non-secure unless the Office has a commercial arrangement with a service provider in order to maintain confidentiality and a secure connection to that website. Consequently, extreme caution must be exercised when using the Internet as a search tool where (as in most cases) the international application has not yet been published. Where a relevant database is accessible via the Internet, but an alternative secure connection to the same database is accessible, the secure connection must be used. Where no secure connection to a database on the Internet is available, the search may be conducted on the Internet using generalized search terms representing combinations of features that relate to the claimed invention, which have already been shown to exist in the state of the art.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty
StatutoryPermittedAlways
[mpep-1843-01-6734da6129f1da35f66e0d4b]
Search Terms on Non-Secure Websites Must Be Handled Cautionously
Note:
When searching for prior art before an international application is published, extreme caution must be taken to ensure search terms used on non-secure websites are not observed by third parties.

When conducting the search, it may be necessary to make use of the Internet as a search tool. Where the international application has not yet been published at the time of the search, there exists the danger that search terms used in the search on non-secure Internet search engines or in databases available on the Internet may be observed by third parties. Accordingly, all websites must be treated as non-secure unless the Office has a commercial arrangement with a service provider in order to maintain confidentiality and a secure connection to that website. Consequently, extreme caution must be exercised when using the Internet as a search tool where (as in most cases) the international application has not yet been published. Where a relevant database is accessible via the Internet, but an alternative secure connection to the same database is accessible, the secure connection must be used. Where no secure connection to a database on the Internet is available, the search may be conducted on the Internet using generalized search terms representing combinations of features that relate to the claimed invention, which have already been shown to exist in the state of the art.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty
StatutoryRequiredAlways
[mpep-1843-01-892a7d17d486061bfbd56436]
Internet Search Must Use Secure Connections for Unpublished Applications
Note:
When searching for prior art on the Internet, secure connections must be used if no commercial arrangement with a service provider is in place to maintain confidentiality.

When conducting the search, it may be necessary to make use of the Internet as a search tool. Where the international application has not yet been published at the time of the search, there exists the danger that search terms used in the search on non-secure Internet search engines or in databases available on the Internet may be observed by third parties. Accordingly, all websites must be treated as non-secure unless the Office has a commercial arrangement with a service provider in order to maintain confidentiality and a secure connection to that website. Consequently, extreme caution must be exercised when using the Internet as a search tool where (as in most cases) the international application has not yet been published. Where a relevant database is accessible via the Internet, but an alternative secure connection to the same database is accessible, the secure connection must be used. Where no secure connection to a database on the Internet is available, the search may be conducted on the Internet using generalized search terms representing combinations of features that relate to the claimed invention, which have already been shown to exist in the state of the art.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty
StatutoryRequiredAlways
[mpep-1843-01-ac95204531d2d3794e07bfc8]
Secure Connection Required for Internet Databases
Note:
When a relevant database is accessible via the internet, a secure connection must be used instead of an insecure one.

When conducting the search, it may be necessary to make use of the Internet as a search tool. Where the international application has not yet been published at the time of the search, there exists the danger that search terms used in the search on non-secure Internet search engines or in databases available on the Internet may be observed by third parties. Accordingly, all websites must be treated as non-secure unless the Office has a commercial arrangement with a service provider in order to maintain confidentiality and a secure connection to that website. Consequently, extreme caution must be exercised when using the Internet as a search tool where (as in most cases) the international application has not yet been published. Where a relevant database is accessible via the Internet, but an alternative secure connection to the same database is accessible, the secure connection must be used. Where no secure connection to a database on the Internet is available, the search may be conducted on the Internet using generalized search terms representing combinations of features that relate to the claimed invention, which have already been shown to exist in the state of the art.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty
StatutoryPermittedAlways
[mpep-1843-01-3ff1b8768d20e442be37fe2c]
Search Terms for Non-Secure Internet
Note:
Use generalized search terms related to the claimed invention and existing state of the art when no secure connection to a database is available on the internet.

When conducting the search, it may be necessary to make use of the Internet as a search tool. Where the international application has not yet been published at the time of the search, there exists the danger that search terms used in the search on non-secure Internet search engines or in databases available on the Internet may be observed by third parties. Accordingly, all websites must be treated as non-secure unless the Office has a commercial arrangement with a service provider in order to maintain confidentiality and a secure connection to that website. Consequently, extreme caution must be exercised when using the Internet as a search tool where (as in most cases) the international application has not yet been published. Where a relevant database is accessible via the Internet, but an alternative secure connection to the same database is accessible, the secure connection must be used. Where no secure connection to a database on the Internet is available, the search may be conducted on the Internet using generalized search terms representing combinations of features that relate to the claimed invention, which have already been shown to exist in the state of the art.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty
Topic

Patent Cooperation Treaty

3 rules
StatutoryRequiredAlways
[mpep-1843-01-a676a03b71def58075badd48]
Analogous Arts Determined by Invention’s Essential Function
Note:
The determination of analogous arts should be based on the necessary essential function or use of the invention, not just the specific functions stated in the international application.

(c) The question what arts are, in any given case, to be regarded as analogous shall be considered in the light of what appears to be the necessary essential function or use of the invention and not only the specific functions expressly indicated in the international application.

Jump to MPEP SourcePatent Cooperation TreatyInternational Searching Authority (ISA)International Search
StatutoryInformativeAlways
[mpep-1843-01-2a1f27096195f96a987b6316]
Objective of International Search
Note:
To discover relevant prior art for determining if the claimed invention is new and involves an inventive step.

The objective of the international search is to discover relevant prior art (PCT Article 15(2)). “Prior art” consists of everything which has been made available to the public anywhere in the world by means of written disclosure (including drawings and other illustrations); it is relevant in respect of the international application if it is capable of being of assistance in determining that the claimed invention is or is not new and that the claimed invention does or does not involve an inventive step (i.e., that it is or is not obvious), and if the making available to the public occurred prior to the international filing date for the purposes of the international search report and prior to the earliest validly claimed priority date for the purposes of the written opinion of the International Searching Authority. For further details, see PCT Rules 33, 43bis.1(b) and 64.

Jump to MPEP SourcePatent Cooperation TreatyInternational Filing DateInternational Searching Authority (ISA)
StatutoryInformativeAlways
[mpep-1843-01-f14dc1fdb6c73b60b46f619c]
Oral Disclosures Not Prior Art Unless Written
Note:
An oral disclosure is not considered prior art unless it is supported by a written disclosure made public before the international filing date.

A non-written disclosure such as an oral disclosure, use, exhibition or other means of disclosure is not relevant prior art for the purposes of the international search unless it is substantiated by a written disclosure made available to the public prior to the international filing date and it is the written disclosure which constitutes the prior art. However, if the date on which the written disclosure was made available to the public was on or after the filing date of the international application under consideration, the search report should separately mention that fact and the date on which the written disclosure was available, even though such a written disclosure does not meet the definition of relevant prior art in the international phase, so long as the non-written disclosure was made available to the public on a date prior to the international filing date since such a non-written disclosure may be considered to be prior art under national law in the national phase. See PCT Rules 33.1(b), 64.2 and 70.9.

Jump to MPEP SourcePatent Cooperation TreatyInternational Filing DateNationals and Residents
Topic

International Searching Authority (ISA)

3 rules
StatutoryRequiredAlways
[mpep-1843-01-a8b35449f922ba187565e19a]
Equivalent Subject Matter Must Be Searched
Note:
The international search must cover all subject matter generally recognized as equivalent to the claimed invention, even if it differs in specifics from what is described in the application.

(d) The international search shall embrace all subject matter that is generally recognized as equivalent to the subject matter of the claimed invention for all or certain of its features, even though, in its specifics, the invention as described in the international application is different.

Jump to MPEP SourceInternational Searching Authority (ISA)International SearchPatent Cooperation Treaty
StatutoryInformativeAlways
[mpep-1843-01-5b642103f8201bb97c566f12]
Objective of International Search
Note:
The international search aims to identify prior art that can assist in determining the novelty and inventive step of the claimed invention.

The objective of the international search is to discover relevant prior art (PCT Article 15(2)). “Prior art” consists of everything which has been made available to the public anywhere in the world by means of written disclosure (including drawings and other illustrations); it is relevant in respect of the international application if it is capable of being of assistance in determining that the claimed invention is or is not new and that the claimed invention does or does not involve an inventive step (i.e., that it is or is not obvious), and if the making available to the public occurred prior to the international filing date for the purposes of the international search report and prior to the earliest validly claimed priority date for the purposes of the written opinion of the International Searching Authority. For further details, see PCT Rules 33, 43bis.1(b) and 64.

Jump to MPEP SourceInternational Searching Authority (ISA)International Search ReportInternational Search
StatutoryRequiredAlways
[mpep-1843-01-9e44f9f7ba67093d75a7a45f]
International Searching Authority Must Consult Minimum Documentation
Note:
The International Searching Authority must search for relevant prior art and consult the minimum documentation as required by PCT rules.

The International Searching Authority must endeavor to discover as much of the relevant prior art as its facilities permit (PCT Article 15(4)), and, in any case, must consult the so-called “minimum documentation” (PCT Rule 34).

Jump to MPEP SourceInternational Searching Authority (ISA)International Search ReportInternational Search
Topic

35 U.S.C. 103 – Obviousness

1 rules
StatutoryRequiredAlways
[mpep-1843-01-7ec4800173745c999987801d]
Relevant Prior Art Before Filing Date Required
Note:
The rule requires that all written disclosures of prior art made public before the international filing date be considered to determine if an invention is new and involves an inventive step.

(a) For the purposes of Article 15(2), relevant prior art shall consist of everything which has been made available to the public anywhere in the world by means of written disclosure (including drawings and other illustrations) and which is capable of being of assistance in determining that the claimed invention is or is not new and that it does or does not involve an inventive step (i.e., that it is or is not obvious), provided that the making available to the public occurred prior to the international filing date.

Topic

Secrecy Orders

1 rules
StatutoryRequiredAlways
[mpep-1843-01-ebf6555802216f8b3a7f7dff]
Search Analogous Arts Regardless of Classification
Note:
The search must cover the classified art and any analogous arts, even if not classified in the same area.

(b) Consequently, not only shall the art in which the invention is classifiable be searched but also analogous arts regardless of where classified.

Jump to MPEP SourceSecrecy Orders
Topic

Maintenance Fee Payment

1 rules
StatutoryRequiredAlways
[mpep-1843-01-27a0e58847b7402c85e85d64]
Search Based on Claims and Description
Note:
The search must focus on the claims with consideration of the description and drawings, emphasizing the inventive concept.

(a) International search shall be made on the basis of the claims, with due regard to the description and the drawings (if any) and with particular emphasis on the inventive concept towards which the claims are directed.

Jump to MPEP SourceMaintenance Fee Payment
Topic
1 rules
StatutoryRequiredAlways
[mpep-1843-01-8317b3f44cec0f77b9d5eef7]
Relevant Date for PCT National Stage Search
Note:
The international filing date of the application, or the earlier application's filing date if a valid priority claim is made, unless the International Preliminary Examining Authority deems it invalid.
(b) For the purposes of paragraph (a), the relevant date shall be:
  • (i) subject to items (ii) and (iii), the international filing date of the international application under international preliminary examination;
  • (ii) where the international application under international preliminary examination claims the priority of an earlier application and has an international filing date which is within the priority period, the filing date of such earlier application, unless the International Preliminary Examining Authority considers that the priority claim is not valid;
  • (iii) where the international application under international preliminary examination claims the priority of an earlier application and has an international filing date which is later than the date on which the priority period expired but within the period of two months from that date, the filing date of such earlier application, unless the International Preliminary Examining Authority considers that the priority claim is not valid for reasons other than the fact that the international application has an international filing date which is later than the date on which the priority period expired.
Jump to MPEP SourceSearch in National StageArticle 19 Amendment ScopeArticle 19 Amendment Timing
Topic

Interviews in National Stage

1 rules
StatutoryRecommendedAlways
[mpep-1843-01-1b091ff1a620a6e775042eb9]
Documents Contributing to Understanding Invention
Note:
Examiners should note documents that contribute to understanding the invention but should not search for them unless necessary.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceInterviews in National StageArticle 19 Amendment ScopeArticle 19 Amendment Timing
Topic

International Search Report

1 rules
StatutoryRequiredAlways
[mpep-1843-01-af5873d3651e611913730ff9]
Non-Prior Art Documents Can Show Universal Facts
Note:
Examiners can cite documents that post-date the claimed invention to show universal facts like material properties or scientific facts, and must recognize different Offices may have varying definitions of prior art effective dates.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceInternational Search ReportSearch in National StageArticle 19 Amendment Scope
Topic

Article 19 Amendment Timing

1 rules
StatutoryPermittedAlways
[mpep-1843-01-0a4054b01ce6544ce2376905]
Review Prior Art from Related U.S. Application
Note:
Examiners must review prior art published within one year of a related U.S. national application for any written disclosures by the applicant, even if not considered prior art in that application.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

Jump to MPEP SourceArticle 19 Amendment TimingInternational Filing DateEffect of International Filing
Topic

Nationals and Residents

1 rules
StatutoryInformativeAlways
[mpep-1843-01-8db70e669de3120035982957]
Minimize National Stage Searching
Note:
Examiners should perform a thorough international search to avoid additional national stage searches, focusing on relevant prior art and common inventors' work.

Examiners are also encouraged to cite prior art that might be of assistance in determining whether other requirements are fulfilled, such as sufficient support of the claims by the description and industrial applicability. The examiner should also note any documents that may be of importance for other reasons, such as documents putting doubt upon the validity of any priority claimed, documents contributing to a better or more correct understanding of the claimed invention, and documents illustrating the technological background, but the examiner should not spend time in searching for these documents, nor the consideration of such matters unless there is a special reason for doing so in a particular case. Documents which do not qualify as prior art because they post-date the claimed invention may nevertheless be cited to show a universal fact, such as characteristics or properties of a material, or a specific scientific fact, or to show the level of ordinary skill in the art. Furthermore, examiners must recognize that different designated Offices may have different definitions of what is the effective date of prior art. Accordingly, when performing the search, examiners should be mindful to pick out and select for citation, where appropriate, prior art which may be relevant in offices other than the one in which they are situated. However, the examiner need not expand the search beyond the standard search parameters to discover such art. Where the search has been performed and such potentially relevant prior art has been identified, examiners are encouraged to, for example, cite all relevant art published prior to the international filing date even if that art and the international application under consideration have common applicants and/or inventors. As such, if the examiner is basing the international search on a prior search performed in a prior related U.S. national application, it may be necessary for the examiner to review the prior art published within the time period of the one year preceding the filing date of the prior U.S. application for any written disclosures based on the applicant’s own work that may have been published within that time period. Any such documents are considered prior art in an international application and are cited on the international search report even though they do not meet the definition of prior art in the prior U.S. national application. A further objective of the international search is to avoid, or at least minimize, additional searching at the national stage.

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

Anticipation/Novelty

1 rules
StatutoryRecommendedAlways
[mpep-1843-01-594b7996f17fbc163331e320]
Inventive Step Determination Using Applicant Acknowledgments
Note:
When assessing inventive step, consider the applicant's admissions in the description as known prior art. These admissions should be used to determine if the claimed invention lacks novelty or inventive step.

In establishment of the written opinion, when determining whether there is inventive step, account should be taken of what the applicant acknowledges in his/her description as known. Such admissions should be regarded as correct and used when considering whether the claimed invention lacks novelty and/or inventive step where appropriate.

Jump to MPEP SourceAnticipation/NoveltyNovelty / Prior Art

Citations

Primary topicCitation
35 U.S.C. 102 – Novelty / Prior ArtMPEP § 1844.01
International Filing DateMPEP § 1878.01(a)
Article 19 Amendment Scope
International Filing Date
International Searching Authority (ISA)
Patent Cooperation Treaty
PCT Article 15(4)
Article 19 Amendment Scope
International Filing Date
International Searching Authority (ISA)
Patent Cooperation Treaty
PCT Rules 33.1(b)
International Searching Authority (ISA)PCT Rule 34
International Filing DatePCT Rule 64.1(b)(ii)

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: 2025-12-31