MPEP § 905 — MPEP § 905
Current through: 2022-07-01

905-Cooperative Patent Classification 
 
 

 
 
 
 
 
 
 
 

 

 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 

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 Chapter 0900 

 Section 905 
 

 
 
 
 
 
 905 Cooperative Patent Classification [R-07.2015]

 Cooperative Patent Classification (CPC) is a bilateral
 classification system jointly developed by the United States Patent and Trademark Office
 (USPTO) and the European Patent Office (EPO). CPC is jointly managed and maintained by both
 offices and is available for public search for classification.
 

 
 905.01 Classification Scheme for CPC [R-07.2015]

 The CPC classification system arranges subject matter into
 hierarchical arrays. 
 

 
 (A) The highest array or level is the Section.

 (B) Each section is subdivided into Classes.

 (C) Each class is subdivided into one or more
 subclasses.
 

 (D) Each subclass is broken down into Groups (main groups
 and subgroups).
 

 
 Each part of this hierarchical structure is identified by
 classification symbols. Specifics about each element of the classification symbol are
 described below.
 

 (A) Section Symbol – Each section is designated by one of
 the capital letters A through H and has an associated section title. There are nine
 sections, eight of which correlate to the sections of the International Patent
 Classification (IPC). The ninth section is used for classifying documents covering
 subject matter pertaining to a plurality of the sections. The table below shows the
 sections with their associated CPC and IPC section titles.
 

 

 

 

 

 
 
 
 
 Letter Designation 
 CPC Section 
 IPC Section 
 

 
 A 
 Human Necessities 
 Human Necessities 
 

 
 B 
 Performing Operations;
 Transporting
 
 Performing Operations;
 Transporting
 
 

 
 C 
 Chemistry;
 Metallurgy
 
 Chemistry;
 Metallurgy
 
 

 
 D 
 Textiles; Paper 
 Textiles; Paper 
 

 
 E 
 Fixed Construction 
 Fixed Construction 
 

 
 F 
 Mechanical Engineering;
 Lighting; Heating; Weapons; Blasting Engines or Pumps
 
 Mechanical Engineering;
 Lighting; Heating; Weapons; Blasting Engines or Pumps
 
 

 
 G 
 Physics 
 Physics 
 

 
 H 
 Electricity 
 Electricity 
 

 
 Y 
 General Tagging of New
 Technological Developments; General Tagging of Cross-over technologies
 spanning over several sections of the IPC; technical subjects covered by
 former USPC cross reference art collections and digest
 
 
 

 
 
 (B) Class Symbol – Each class symbol consists of the
 section symbol followed by a 2 digit number (e.g., C07). Each class symbol is associated
 with a title.
 

 (C) Subclass Symbol – Each subclass symbol consists of the
 class symbol followed by a letter (e.g., C07D). Each subclass symbol is associated with
 a title.
 

 (D) Main Group Symbol – Each main group symbol consists of
 the subclass symbol followed by a one- to four- digit number, the oblique stroke, and
 the number 00 (e.g. C07D 203/00). Each main group number is associated with a main group
 title which precisely defines a field of subject matter within the scope of its subclass
 and a definition.
 

 (E) Subgroup Symbol – Each subgroup symbol consists of the
 main group symbol, but the number “00” in the main group symbol is replaced with an
 alternative number of up to six digits (e.g. C07D 203/02). Each subgroup symbol is
 associated with a title and definition. 
 

 
 Example:

 CPC Symbols C07D 203/00 or C07D 203/02

 

 

 
 905.01(a) CPC Titles [R-07.2015]

 The title associated with a CPC symbol defines the scope
 of the subject matter covered by that symbol. In general, the title of every CPC
 organizational division is read as including the titles of all its superior
 organizational units. For example, the title of a CPC subgroup is interpreted as
 including the title of its parent group and that parent’s group title all the way up
 to, and including, the section title.
 

 Titles in the CPC system are generally in the form of
 single part or multipart titles which are described below.
 

 
 (A) Single part title -- Defines or represents the
 subject matter of a single concept or information.
 

 Example:

 A47C 1/00 Chairs adapted for special purposes

 (B) Multipart title (separated by semicolons) -- A
 semicolon in a CPC title delineates coverage of two distinct and separate
 information entities that should be considered stand-alone things for purposes
 of coverage.
 

 Example:

 F25D REFRIGERATORS; COLD ROOMS; ICE-BOXES;
 COOLING OR FREEZING APPARATUS NOT COVERED BY ANY OTHER SUBCLASS
 

 The three semicolons in the above example inform
 us that the subclass covers four distinct and separate entities: 1)
 refrigerators, 2) cold rooms, 3) ice boxes, and 4) other types of cooling or
 freezing apparatus not covered by any other subclass, therefore it is a
 residual to all cooling and freezing apparatus not elsewhere classified in
 CPC.
 

 
 
 905.01(a)(1) References within CPC Titles [R-07.2015]

 References are statements enclosed within
 parentheses in titles. The references point to other classification places that
 may be of interest. References apply to the classification place they appear and
 to all hierarchically lower classification places, unless stated otherwise.
 

 Examples of References:

 

 Example:

 B64C AEROPLANES; HELICOPTERS (air-cushion vehicles
 B60V)
 

 (A) Limiting references

 A limiting reference is found in the group titles of
 the scheme and exclude specific subject matter from the scope of the
 classification place, when this subject matter would otherwise fulfill all the
 requirements of the classification place (or would be covered by that place).
 Limiting references are pertinent for classification purposes. Limiting references
 limit the scope of a place, thereby avoiding overlap. 
 

 Example:

 A01F 7/02 . With rotating tools (threshing cylinders
 or concaves A01F 12/18)
 

 (B) Precedence references

 A precedence reference is a special example of a
 limiting reference that always refers to another group or groups taking
 “precedence” within the same subclass. The purpose of a precedence reference is to
 remove overlap between two similar groups.
 

 Example:

 G02B 1/00 Optic elements

 1/04 . made of organic materials (1/08 takes
 precedence)
 

 

 
 905.01(a)(2) Notes Found in CPC schemes [R-07.2015]

 Notes are supplementary statements that follow a CPC
 class, subclass, main group, or subgroup title. Instruction in a “Note” is applied
 only to the CPC place where it appears, including all its hierarchically lower
 places. For example, a note after a class title applies to the entire class. A
 note after a subclass title applies only to the subclass, a note after a main
 group applies only to the main group, etc. Notes may be used to explain the scope,
 define terminology, or indicate specific classification rules.
 

 

 
 905.01(a)(3) Warnings Found in CPC schemes [R-07.2015]

 A warning is used in CPC schemes for signaling
 deviations from IPC or incomplete classification. A warning may include a listing
 of IPC groups not included within CPC and the CPC group which covers the relevant
 subject matter. A warning also may be used to indicate the deletion or
 transferring of CPC groups and reclassification notices.
 

 

 
 905.01(a)(4) Guidance Headings Found in CPC
 Schemes [R-07.2015]
 

 Guidance headings may be provided as follows:

 
 (A) When a large part of a subclass relates to a
 common subject matter, a guidance heading indicating that subject matter may
 be provided at the beginning of that part. 
 

 (B) As a title, without any associated symbol, of
 subject matter preceding several main groups.
 

 (C) To describe common subject matter of several
 main groups.
 

 
 

 

 

 
 905.02 CPC Definitions [R-07.2015]

 Each CPC definition, whether it is a subclass, main group,
 or subgroup definition, must adhere to the same definition template which defines the
 permissible elements and formatting. Most CPC schemes will include supplementary
 definitions to clarify the scope of classification places as well as to inform the user
 of special classification rules in that area. Definitions are provided for CPC
 subclasses, main groups or subgroups, but not for CPC sections or classes. Not all CPC
 subclasses or groups have definitions. When a title is sufficiently clear to describe
 the scope of the classification place, a definition statement is not necessary.
 

 A definition may include the following:

 
 (A) Definition title – The definition title always
 reflects the title of the classification place being defined. For example, a
 subclass definition will have the same title as the title of the subclass; a group
 definition will have the same title as the title of the group.
 

 (B) Definition Statement - The scope of the definition
 statement should essentially be the same as the scope of the title. The definition
 statement should clearly elaborate the meaning of the classification place rather
 than merely restating its title. The definition statement should provide a
 positive description of the subject matter appropriate for the classification
 place, rather than a negative description of the subject matter excluded from the
 classification place. The appropriate classification places for the excluded
 subject matter are found under “Limiting References”.
 

 (C) References relevant to classification in a
 subclass/group
 
 (1) Limiting and precedence references – See
 MPEP § 905.01(a)(1) .
 

 
 
 (2) Specially adapted references – Specially
 adapted references are references from function-oriented (general) to
 application-oriented places. The subject matter indicated by a specially
 adapted reference could be classified in the instant classification place,
 and in the classification place where the reference points to, or both. 
 

 
 
 (3) Residual references – Residual references from
 residual subclasses (defined as such in the title of the subclass or the
 definition statement) to non-residual places should appear in this
 section.
 

 (4) Informative references -- Informative
 references are references that indicate the location of subject matter that
 could be of interest for searching, but are not within the scope of the
 classification place where the reference occurs. References from
 application-oriented places to function-oriented places are informative.
 
 

 
 

 (D) Special rules of classification within the
 subclass/group -- This section contains special classification rules, which apply
 only within the subclass/group and not between subclasses/groups. Examples of such
 classification rules are the first place or the last place priority rules. 
 
 (1) First place priority rule: When a document is
 classifiable in more than one group in a scheme, the one highest in the
 scheme is allocated to the document.
 

 (2) Last place priority rule: When a document is
 classifiable in more than one group in a scheme, the one lowest in the
 scheme is allocated to the document.
 

 
 
 (3) Common rule: When a document is classifiable in
 more than one group in a scheme, the classification symbol that most
 completely covers the invention is allocated to the document.
 

 In CPC, as with IPC, in the absence of any
 classification rule, common rule, defined in (D)(3) above, is the governing
 classification rule.
 

 
 

 (E) Glossary of terms -- This section consists of
 definitions for significant words or phrases found in the titles or definition
 statements. Terms found exclusively in patent documents or in technical
 literature, but not in the scheme or the definition statement, will normally
 appear in the synonyms and keywords section.
 

 (F) Synonyms and Keywords - This is an optional section
 establishing synonyms, keywords, abbreviations and acronyms from terms used in the
 patent documents themselves or in technical literature. This section aids in
 formulating search queries in electronic searching in the technical field. This
 section may include definitions of such terms when they do not appear in the
 scheme or the definition statement.
 

 
 

 
 905.03 Classifying in CPC [R-10.2019]

 The primary purpose of classification is to facilitate the
 retrieval of technical subject matter. In order to reliably retrieve technical subject
 matter using the CPC classification system it is important for all technical subject
 matter to be consistently classified.
 

 CPC has its own classification rules which appear in the
 scheme, definitions, or both. See MPEP § 905.02 . In the absence of any
 specified classification rules in the scheme and definitions, classification practice
 follows the rules used in the IPC, as set forth in the IPC Guide. The IPC Guide is
 available at www.wipo.int/classifications/ipc/en/ .
 

 
 905.03(a) The CPC Database [R-07.2022]

 The CPC database maintains technical information
 regarding the patent family documents for each patent document included. Patent
 documents contain two types of technical information to classify. These are invention
 information and additional information. All of the symbols which are allocated to an
 application, in accordance with CPC guidance, define the application's classification
 picture.
 

 I. PATENT FAMILY A patent family is a group of documents related to
 each other by common priorities. Examples include a pre-grant publication (PGPub)
 of an application and any patent issued from the same application. A parent and
 divisional application also are considered as being in the same family.
 

 In the CPC database, CPC symbols are associated with
 patent families. When a document is classified in CPC, the symbol associated with
 the document is stored in the CPC database as an association between the symbol
 and patent family in which the document is a member. This means that whenever a
 CPC symbol is allocated to a document all the documents in the family receive the
 same symbol.
 

 In the CPC database, a document cannot be classified
 independently of the other documents belonging to the same patent family. Every
 classification symbol associated with a document, i.e., allocated to the document,
 is associated with every patent document in the family. Each allocation of a
 symbol to a patent family has additional attributes stored in the CPC database.
 These include the following: 
 

 
 Classification symbol

 Type (Invention/other additional
 information)
 

 Position (First/later classification)

 II. INVENTION INFORMATION (OBLIGATORY/MANDATORY) All disclosed invention information in a patent
 document must be classified in CPC in order for a user to retrieve the invention
 information from the system. Therefore, it is mandatory to classify all the
 invention information disclosed in each family to be classified. 
 

 Invention information is technical information in
 the total disclosure of a patent document (for example, description, drawings,
 claims) that represents an addition to the state of the art. The invention
 information is determined in the context of the state of the art, using guidance
 provided by the claims of the patent document, with due regard given to the
 description and the drawings. “Addition to the state of the art” means all novel
 and unobvious subject matter specifically disclosed in a patent document, which
 advances the state of the art, i.e., the technical subject matter disclosed that
 is not already in the public domain. 
 

 Patent documents should not be classified as a
 single entity. Rather, all different inventive entities, claimed or disclosed
 within the patent document, should be identified and separately classified. Such
 different inventive entities are represented by different claims, alternative
 variants or different categories of subject matter (for example, a product and a
 method of its production).
 

 III. ADDITIONAL INFORMATION (DISCRETIONARY) Additional information is non-trivial technical
 information which does not in itself represent an addition to the state of the art
 but might constitute useful information for the searcher. The additional
 information complements the invention information by identifying the constituents
 of a composition or mixture; elements or components of a process or structure; or
 use or applications of classified technical subjects. 
 

 Unlike invention information which must be
 classified, any additional non-trivial technical information that would be useful
 for search is classified on a discretionary basis.
 

 IV. C-STAR (C*) INFORMATION
 (OBLIGATORY/MANDATORY) A C-STAR (C*) is applied to an allocated symbol
 from the classification picture on an application when that symbol represents
 at least one concept that is claimed. C* designations should be applied to
 symbols regardless of type or position (any of family, invention, and
 additional). No new CPC symbols should be allocated merely to address C*s.
 Narrow/specific CPC symbols that fall within the claimed subject matter shall
 be designated as C*. Narrowly allocated symbols that overlap with broadly
 defined claims shall be designated as C*. There is no limit to the number of
 the CPC symbols within the classification picture of an application that can be
 designated as a C*, but at least one CPC symbol must be designated as a C*. 
 

 A. Type Attributes Every classification allocation has a “type”
 attribute. There are two values that this attribute may have: 
 

 
 (A) Invention Information

 When allocating CPC symbols to a
 document based on disclosed invention information, the type attribute
 is set to “invention.” This is typically done by putting the symbol
 being allocated in the “mandatory” section of the classification form.
 
 

 (B) Additional information

 When allocating CPC symbols to a
 document based on disclosed information that is not inventive, the
 type attribute is set to “additional”. This is typically done by
 putting the symbol being allocated in the “discretionary” section of
 the classification form.
 

 (C) Position Attribute
 
 First - Each patent family will
 possess a first-listed CPC classification symbol which is
 selected from the required classifications for the inventive
 subject matter of the patent family. This “first” CPC
 classification is the inventive classification symbol which most
 adequately represents the invention as a whole for the patent
 family. In situations where a later-published family member
 possesses a different first-listed CPC classification, this will
 override the previous first-listed classification (which will be
 retained for the patent family as an inventive classification
 symbol). There is one and only one “first” position attribute
 per patent family. The first attribute is associated with the
 invention symbol that most completely covers the technical
 subject matter of the disclosed invention. The first position
 symbol is identified as the first mandatory symbol listed on the
 classification form. 
 

 Later - If a symbol allocation is
 not the “first” position symbol, its position attribute is
 “later”. All invention allocations that are not “first”
 position, as well as all “additional” type symbols have the
 position attribute “later”. All symbols listed on the
 classification form other than the first listed invention symbol
 receive the position attribute
 
 "later"
 
 
 .
 

 
 

 
 

 
 905.03(b) Approach to classification in CPC [R-07.2022]

 The first step to classifying a document in CPC is to
 identify the subject matter that will be classified. The second step is to identify
 appropriate groups in CPC covering the subject matter to be classified.
 

 The general rules for identifying the subject matter to
 classify in CPC are as follows: 
 

 
 (A) All subject matter covered by the claims of a
 patent document must be classified as invention information along with any
 novel and unobvious constituents or components (subcombinations) of the claimed
 subject matter. Classification should be based on the subject matter of each
 claim as a whole and on each inventive embodiment within a claim. 
 

 (B) Any unclaimed subject matter in the disclosure
 that is novel and unobvious must also be classified as invention
 information.
 

 (C) It is desirable to classify or index any
 additional information complementing the invention information, mentioned in
 the claims or in the unclaimed disclosure, if it is useful for search
 purposes.
 

 (D) A subcombination of the subject of the invention
 if the subcombination is itself novel and non-obvious.
 

 
 The scheme or definitions in particular areas should be
 consulted to determine if additional classification or index codes are required. For
 example, places in CPC where multi-aspect classification is especially desirable are
 indicated by a note. See MPEP § 905.02 . Depending on the
 nature of the subject matter concerned, such a note prescribes obligatory
 classification of the subject matter according to the indicated aspects, or contains
 a recommendation for multi-aspect classification if it is desirable for increasing
 the efficiency of the patent search.
 

 The general procedure for identifying the appropriate
 groups for covering the subject matter to be classified is as follows: 
 

 
 (A) Identify the appropriate subclasses covering the
 subject matter to be classified.
 
 (1) The scope of a subclass is defined by its
 title and definition. In order to determine a candidate subclass for
 classification one must review the titles of available subclasses for
 scope coverage.
 

 
 
 (2) After a candidate subclass has been
 identified, the subclass notes, references and definition should be
 consulted to verify that the scope of the subclass covers the subject
 matter to be classified.
 

 
 
 (3) The preceding steps should be repeated
 until a candidate subclass is verified to cover the subject matter to be
 classified.
 

 
 

 (B) Identify the appropriate group(s) covering the
 subject matter to be classified.
 
 (1) Identify candidate main groups that cover
 the subject matter to be classified.
 

 
 
 (2) Verify that the notes, references, and
 definitions do not exclude the subject matter to be classified, and that
 the group is in active use (not under reclassification).
 

 
 The technical subject matter of many inventions
 is completely covered by only one group in the subclass. In this situation,
 classification is made in the one group covering the technical subject matter
 of the invention. 
 

 
 

 

 When multiple groups cover the technical subject
 matter of a single invention, classification is generally made in the group
 which most completely covers the invention. Within a group array, a group that
 covers the technical subject matter of the invention to be classified generally
 covers the subject matter more completely than the parent of that group.
 

 
 

 

 When multiple groups cover the invention equally
 well, groups are selected according to the following rules:
 

 
 (a) In the case where the Last Place Priority
 Rule (LPPR) is applicable to the groups under consideration, then the
 group lowest in the scheme is selected for classification.
 

 (b) In the case where the First Place Priority
 Rule (FPPR) is applicable to the groups under consideration, then the
 group highest in the scheme is selected for classification.
 

 (c) In the case where neither LPPR nor FPPR are
 applicable to the groups under consideration, then classification is made
 in each group.
 

 
 
 (3) Whenever classifying into a group, the
 scheme notes and definitions should be consulted for guidance regarding
 special rules of classification applicable to the CPC groups at issue,
 such as the requirement for Multiple Aspect classification or
 Indexing.
 

 
 
 (4) Whenever classifying into a group, the
 scheme should always be consulted for precedence notes and references
 that indicate a preference for classification in another group.
 Precedence notes and limiting reference should always be followed when
 applicable.
 

 
 
 (5) Identify application/functional
 classification places. Occasionally, two or more subclasses/groups are
 identified that cover the disclosed invention information from different
 aspects. For example, one classification place might cover specific uses
 of the invention, whereas the second classification place may cover the
 generic uses of the invention. These types of coverage are respectively
 referred to as application and functional classification places. In
 general, classification is made in the application classification place
 when application specific adaptations are disclosed. For example, a pump
 specially adapted to replace a heart is classified in A61M 1/10, whereas
 pumps, in general, without any disclosed special adaptation are
 classified in F04B, F04C, F04D, or F04F depending on the specific
 structure of the pump. When uses of inventions are nominally disclosed,
 classification is generally made in functional classification places.
 

 
 
 (6) Identify genus/species classification
 places. 
 
 (a) In the case where an invention is
 generically disclosed classification is made to the classification
 place covering the generic invention. Even in cases where species
 are nominally disclosed, such as by name only, classification is
 still made to the generic classification place. 
 

 (b) In the case where fully enabled
 species are disclosed, classification is required in the
 classification places covering the individual species. 
 

 
 

 
 
 (7) Identify residual classification places
 
 

 

 In the event a classification place that
 explicitly covers the technical features of the invention to be
 classified cannot be identified, then classification should be made to a
 “residual” classification place. Residual classification places can be
 found at both subclass and group levels. Residual classification places
 are identifiable by their titles, which typically indicate they cover
 subject matter not elsewhere covered.
 

 

 
 

 
 When an application is passed to issue, it is the duty
 of each primary examiner to personally review the classification picture of the
 application in the issuing classification boxes on the Issue Classification form.
 This form provides space for the full name of the "Primary Examiner" to show that the
 review has been made. An examiner with full signatory authority who acts personally
 on an application and sends it to issue should stamp and sign their name on the Issue
 Classification form ONLY in the "Primary Examiner" space.
 

 

 
 905.03(c) Combination Sets [R-07.2015]

 In certain CPC fields, the examiner has the ability to
 create and search on combinations of CPC symbols (provided as groupings of symbols),
 each symbol in a grouping has a defined relationship to the other symbols in its
 grouping. These groupings are termed combination sets, and provide an enhanced
 mechanism for storing and retrieving classification information from patent
 documents. While the usage of CPC combination sets is confined mostly to the chemical
 fields, there are numerous instances where combination sets are used in mechanical
 and electrical fields.
 

 The first symbol in a combination set is termed the
 base classification symbol, and determines the authorization for creation or deletion
 of combination sets within the field of the base symbol. The other members of a
 combination set possess the same Invention or Additional information, i.e. INV/ADD
 attribute as the base symbol, with an ordered ranking to denote their positioning
 within the combination set. 
 

 Guidance on the creation of combination sets is
 detailed in the CPC classification definitions. For example, the combination sets in
 a given field may denote the sequence of operations in a multi-step process, while in
 another field, the combination sets may denote the product and its method of
 manufacture. It is even possible to have the same CPC symbol appear more than once in
 a given combination set, with the ordering thereof to reflect the occurrence of
 multiple steps provided for by the repeated CPC symbol.
 

 

 

 [top] 

 

 

 
 

 
 

 

 

 

 
 
 
 901-Prior Art 
 901.01-Canceled Matter in U.S. Patent Files 
 901.01(a)-Ordering of Patented and Abandoned Provisional and Nonprovisional Application Files 

 
 

 901.02-Abandoned Applications 

 901.03-Pending Applications 

 901.04-U.S. Patents 
 901.04(a)-Kind Codes 

 
 

 901.05-Foreign Patent Documents 
 901.05(a)-Citation Data 

 901.05(b)-Other Significant Data 

 901.05(c)-Obtaining Copies 

 901.05(d)-Translation 

 
 

 901.06-Nonpatent Publications 
 901.06(a)-Scientific and Technical Information Center (STIC) 

 901.06(b)-Borrowed Publications 

 901.06(c)-Alien Property Custodian Publications 

 901.06(d)-Abstracts, Abbreviatures, and Defensive Publications 

 
 

 901.07-Patent Family Information 

 901.08-Global Dossier Public Access 

 
 

 902-Search Tools and Classification Information 
 902.01-Classification Manual for the U.S. Patent Classification System 
 902.01(a)-Index to the U.S. Patent Classification System 

 
 

 902.02-Class and Subclass Definitions in USPC 
 902.02(a)-Definition Notes in USPC 

 902.02(b)-[Reserved] 

 
 

 902.03-Classification Information 
 902.03(a)-Patent Classification Home Page on the Internet 

 902.03(b)-Patent Classification Home Page on the USPTO Intranet 

 902.03(c)-[Reserved] 

 902.03(d)-[Reserved] 

 902.03(e)-Automated Search Tools: PE2E SEARCH 

 
 

 
 

 903-Classification in USPC 
 903.01-Statutory Authority 

 903.02-Basis and Principles of Classification in USPC 
 903.02(a)-[Reserved] 

 903.02(b)-Scope of a Class in the USPC 

 
 

 903.03-Availability of Foreign Patents 

 903.04-Classifying Applications for Publication as a Plant Patent Application Publication in USPC 

 903.05-Addition, Deletion, or Transfer of U.S. Design Patents by USPC Classification 

 903.06-Harmonized Subclasses 

 903.07-Classifying and Cross-Referencing Design and Plant Applications at Allowance 
 903.07(a)-Cross-Referencing Design and Plant Applications — Keep Systematic Notes During Prosecution 

 
 

 903.08-[Reserved] 
 903.08(a)-[Reserved] 

 903.08(b)-[Reserved] 

 903.08(c)-[Reserved] 

 903.08(d)-[Reserved] 

 903.08(e)-[Reserved] 

 
 

 903.09-[Reserved] 
 903.09(a)-[Reserved] 

 
 

 
 

 904-How to Search 
 904.01-Analysis of Claims 
 904.01(a)-Variant Embodiments Within Scope of Claim 

 904.01(b)-Equivalents 

 904.01(c)-Analogous Arts 

 
 

 904.02-General Search Guidelines 
 904.02(a)-Classified Search 

 904.02(b)-Search Tool Selection 

 904.02(c)-Internet Searching 

 
 

 904.03-Conducting the Search 

 904.04-Search of Related Post-Grant Proceedings 

 
 

 905-Cooperative Patent Classification 
 905.01-Classification Scheme for CPC 
 905.01(a)-CPC Titles 
 905.01(a)(1)-References within CPC Titles 

 905.01(a)(2)-Notes Found in CPC schemes 

 905.01(a)(3)-Warnings Found in CPC schemes 

 905.01(a)(4)-Guidance Headings Found in CPC Schemes 

 
 

 
 

 905.02-CPC Definitions 

 905.03-Classifying in CPC 
 905.03(a)-The CPC Database 

 905.03(b)-Approach to classification in CPC 

 905.03(c)-Combination Sets 

 
 

 
 

 906-International Classification of Patents for Inventions 

 907-Locarno Classification Designations 

 908-[Reserved] 

 909-Routing and Docketing of Applications 
 909.01-Assignment, Transfer and Classification Challenges under Cooperative Patent Classification (CPC) 
 909.01(a)-New Applications in CPC 

 909.01(b)-Classification and Assignment to Examiner in CPC 

 909.01(c)-Immediate Inspection of Amendments 

 909.01(d)-Classification Challenge Procedure in CPC 

 
 

 909.02-Applications: Assignment and Transfer in USPC 
 909.02(a)-New Design and Plant Patent Applications under 35 U.S.C. 161 

 909.02(b)-Classification and Assignment to Examiner 

 909.02(c)-Reserved 

 909.02(d)-Transfer Procedure 

 909.02(e)-General Guidelines Governing the Assignment of Nonprovisional Design and Plant Applications for Examination 

 
 

 
 

 

 

 
 

 
 
 

 
 

 

 
 
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 03/09/2026 20:49:44