HANDBOOK ON INDUSTRIAL PROPERTY INFORMATION AND DOCUMENTATION
Ref.: IPC Revision Instructions
page: 5.2.3.0
SPECIFIC INSTRUCTIONS
FOR THE REVISION OF THE IPC
The present Instructions for the Revision of the IPC have been elaborated for the use of the bodies entrusted
with the revision work by the Committee of Experts of the IPC Union, in order that the revision may be carried out in a
consistent manner by these bodies and with the aim of maintaining high degree of standardization in the IPC.
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Date: September 1999
HANDBOOK ON INDUSTRIAL PROPERTY INFORMATION AND DOCUMENTATION
Ref.: IPC Revision Instructions
page: 5.2.3.1
SPECIFIC INSTRUCTIONS FOR THE REVISION OF THE IPC
GENERAL REMARKS
1.
Revision of the sixth edition of the IPC should be carried out with due regard to the revision policy agreed by the
IPC Committee of Experts at its twenty-second session, in October 1993 (see Annex I).
2.
In the following paragraphs, some advice is given on how to proceed when revising the IPC.
GENERAL REMARKS CONCERNING THE REVISION OF THE IPC
3.
In revising the IPC in force, consideration should be given to the Guide, and particular care must be taken in
deciding whether the wording of the place under consideration, together with any hierarchically superior place or places,
is clear in all respects, and whether the references, if any, are correct.
4.
The bodies entrusted with the revision work should carefully consider:
(a)
the order of subject matter in classes, subclasses and groups;
(b)
the use of terms or expressions; and
(c)
the number of groups necessary.
5.
Since the function-oriented principle takes precedence over the application principle (see the IPC Revision
Philosophy, Section 5.2.1, paragraph 10), offices objecting to the function-oriented approach should justify their position
with detailed reasons.
DETAILED INSTRUCTIONS
Wordings in the IPC
6.
(a)
The wording of a place in the IPC must indicate clearly the scope of the place. A note or reference
should always be provided if there is any doubt about the scope of the place.
(b)
In many cases, it is necessary to define particular wordings in addition to the already existing definitions.
Such definitions should appear conveniently close to the highest level at which the wording appears. Repetition of
definitions at lower level should be avoided. However, if deemed desirable, a reference back to the definition at the
higher level may be introduced, for example, in the form “Attention is drawn to the definition of - - - in Note - - -“
Definitions are needed especially for places where it is difficult to see the demarcation intended. If there is no distinction
between two expressions, only one should be used throughout.
(c)
Due consideration must be given to the standardized terminology in any revision work. A limited number
of wordings having standardized meanings have been adopted in the IPC, as set out in paragraphs 31 to 42 of the
Guide. Attention should also be paid to the Glossary of terms or expressions contained in Chapter VI of the Guide. The
terms or expressions used and their spelling, as well as punctuation, should be checked for consistency with the existing
IPC. Particular care should be exercised in the use of terms, as follows:
(i)
when appropriate, the IUPAC (International Union of Pure and Applied Chemistry) nomenclature
should be followed for the presentation of chemical terms;
(ii)
“processes” and “methods” – The term “processes” should be used wherever possible;
(iii)
“apparatus” and “machines” – The term “apparatus,” being generic, can be safely used in all
contexts. However, where it is accepted practice in particular arts to use the term “machines,” in expressions such as
“dynamo-electric machines” or “sewing machines,” the term “apparatus” should preferably not be used;
(iv)
“functional” – This term should only be used if its meaning is clear in the context given.
Otherwise, it should be replaced by an unambiguous wording;
(v)
“material” – This term should be used in its singular form, except when only the plural form makes
(vi)
“invention(s)” – This term should be avoided in the context of classifying.
sense;
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Ref.: IPC Revision Instructions
page: 5.2.3.2
(d)
In class or subclass titles, wordings such as “not covered elsewhere” or “not otherwise provided for”
should be avoided, if possible.
(e)
Class and subclass titles are in capitals. Expressions such as “mechanical part,” “non-mechanical part,”
“chemical part,” “non-chemical part,” etc., when occurring in such titles, are to be considered as a part thereof and
should appear in capitals.
(f)
When a subclass is created, the practice of using only consonants for the last letter of the subclass
symbol should be adhered to, but in cases where special reasons so require the use of vowels, with the exception of “I”
and “O,” would be acceptable.
(g)
Whenever the use of abbreviations appears to be necessary, the use of the abbreviations standardized
by the International Organization for Standardization (ISO) is recommended.
(h)
The use of trademarks should be avoided, but a trademark may be used in examples, if found necessary
in order to clearly describe the subject matter in question. In that case, the trademark should be acknowledged with the
symbol ““. When the use of common tradenames is indispensable, a check whether these tradenames are registered
trademarks should be carried out to the extent possible.
(i)
The use of full names of chemical elements is recommended whenever it is possible. When groupings of
elements are given in the IPC, they should follow the definitions, as given at the beginning of section C of the IPC.
(j)
Except in chemical formulae, Greek letters, e.g., , , , should be spelt out, in order to facilitate
searching by computer.
(k)
When several consecutive groups are transferred to one and the same place, the first and the last groups
transferred should be indicated, even when the first group is a main group.
References
7.
(a)
All references must be carefully checked in respect of correctness of the place referred to. References
should be specific both as to the subject matter referred to and the place where it is covered. References of the type
“- - - specially adapted to a particular field of use, see the relevant places - - -“, giving no examples of such places,
should be avoided.
(b)
Guidance references should be introduced only when such references are considered to be particularly
useful.
(c)
The wording of references should be either the same as that of the place referred to or as close to it as
possible. In particular, the wording of a reference should never refer out matter not clearly covered by the place referred
to. The wording of a reference to a place can never affect the scope of that place.
(d)
References should be worded consistently with one another.
(e)
References should be in alphanumerical order of the places referred to, except that, where they appear in
the subdivisions of a subclass, those relating to other places within the subclass should appear before other references.
Precedence references should always be placed first.
(f)
References to a place should include the symbols of the group or subgroup, as appropriate.
(g)
References between function-oriented places and application places should, preferably, appear in the
function-oriented places. However, when found particularly useful they may appear in application places.
8.
At the end of each revision period, references should be checked and those affected by the amendments to the
IPC approved by the Committee of Experts amended accordingly. This check may be carried out with the aid of a
reversed list of references, prepared by the International Bureau, listing for a given place in the IPC all places where
reference is made to that place.
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Ref.: IPC Revision Instructions
page: 5.2.3.3
Examples
9.
Examples should preferably be given in the plural form.
Guide Headings
10.
Guide headings, if found useful, should be placed before a plurality of successive main groups relating to
common subject matter. Exceptionally, when found necessary, a guide heading may be provided for a single main
group.
Notes
11.
The term “Note,” or its plural form, should be used in all instances.
12.
A note concerning a particular part of a subclass should, in order to draw the attention of the reader, be put in the
most appropriate place. This is normally as close as possible to the beginning of the part concerned.
13.
The presentation and layout of Notes should follow the approved standard, as set forth in Annex II.
Presentation of Subclass Symbols
14.
When two or more subclasses of a class are written together, the symbols of those subclasses should be written
without repeating the class symbol and by separating the subclass letters by commas, e.g., B 21 C, D.
Renumbering of Groups
15.
(a)
Renumbering of a group should take place if the scope of the group is substantially changed, except:
(i)
when a subgroup is created, deleted or amended and the subject matter remains within the same
main group, renumbering of hierarchically higher groups of the same main group is not necessary;
(ii)
when, in exceptional cases, compelling reasons, which should be given, justify that no
renumbering is undertaken.
(b)
Renumbering of a group should not take place if the scope of the group is not substantially changed.
(c)
Changing the scope of a class or a subclass should not normally require changing the symbol of that
class or subclass.
(d)
For the purpose of indicating in the text of the IPC the kind of changes it has undergone, the bodies
entrusted with the revision work should indicate each approved entry that has been changed (in wording or hierarchical
position) in such a way that the scope of one or more groups is affected.
16.
Group numbers which have been used in earlier editions of the IPC should be avoided when renumbering groups
or inserting new groups. However, numbers which have been used in the Classification published by the Council of
Europe in the years 1963 to 1967 may be used in future editions of the IPC, but this use should be limited to the
maximum extent possible.
Subgroup Numbering
17.
Each subgroup symbol consists of the subclass symbol followed by the one- to three-digit number of its main
group, the oblique stroke and a number of at least two digits other than 00. Any third or subsequent digit after the
oblique stroke is to be understood as a decimal subdivision of the digit preceding it. The use of numbers for new
subdivisions is explained in greater detail in Annex III.
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Ref.: IPC Revision Instructions
page: 5.2.3.4
Residual Groups
18.
Whenever existing subdivisions are revised, or new subclasses are created, care must be taken to ensure that
any necessary residual main groups are provided, in order that the schedule may be exhaustive for the subject matter
concerned.
Hierarchical Order
19.
When undertaking substantial revision of a subclass, use of the “last place rule” should be considered, and if the
use of this rule appears to be advantageous it should be used.
20.
In revising the system, care must be taken to check whether a subordinate place fits correctly under the wording
of the next hierarchically higher place.
Check List
21.
When subdivisions of subclasses are created, or when commenting on proposals for such elaborations, the
check list appearing in Annex IV to these Instructions should be borne in mind.
Class and Subclass Indexes
22.
The indexes should be presented in such a way that subordinate entries can be recognized without difficulty.
Main headings should not indicate specific group numbers. The correct punctuation must also be checked.
23.
At the end of each revision period, Class and Subclass Indexes should be checked, and those affected by the
amendments to the IPC approved by the Committee of Experts amended accordingly.
Hybrid Systems
24.
In proceeding with the further development of the IPC, all attempts should be based on applying conventional
classification techniques. However, in specific areas of the IPC, the concept of the hybrid system, that is, a system in
which classifying terms are supplemented by indexing terms, may be introduced when this is found desirable, in order to
improve the effectiveness of the IPC as a search tool.
25.
Indexing codes should identify elements of information about the technical subjects in addition to the information
covered by one or more of the classification symbols. Such elements of information may indicate, for example, the
essential constituents of a composition or mixture, constituent groups of a compound or components of a process or
structure; they may also identify uses or applications of classified technical subjects.
26.
Alphanumerical symbols should be used for the indexing codes, in the same way as the classification symbols,
with the difference that the oblique stroke appearing in the classification symbols should be replaced by a colon, for
example, B 29 K 9:06. The numbering of the indexing codes should be such that truncation of the indexing codes is
feasible when carrying out database searching.
27.
When creating an indexing scheme, its first code number should be chosen on a case by case basis, but,
whenever possible, that number should be 101:00.
28.
Some areas of the IPC are elaborated so that they can serve both as classification schemes and indexing
schemes. However, careful consideration should be given to whether such elaboration of any other area of the IPC
should be undertaken, bearing in mind that such an elaboration is allowed only when justified on the grounds of technical
considerations.
29.
When an indexing scheme has been elaborated, it should be decided whether the indexing codes, when
presented on the patent documents, should be linked or unlinked to the classification symbols with which they are
associated.
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Ref.: IPC Revision Instructions
page: 5.2.3.5
30.
At the beginning of each area with which an indexing scheme may be associated or which constitutes a separate
indexing scheme, a note should appear. The model wordings set forth in Annex II, item 3, should be observed. The
indexing scheme itself is always preceded by a heading.
Revision Concordance Data
31.
For the purpose of establishing the Revision Concordance List, the rapporteurs appointed for the revision
projects concerned should inform the International Bureau of how subject matter will be transferred between places in
the IPC as a result of the amendments approved.
Presentation Of Chemical Structural Formulae
Presentation Of Chemical Structural Formulae In The Ipc
32.
When undertaking revision of a chemical area of the IPC, consideration should be given to the desirability of
presenting chemical structural formulae, in order to facilitate the understanding of the chemical structure of the
compounds classified in the area. Such consideration should always take into account the specific needs of the user
and should not lead to the introduction of chemical formulae for sufficiently well known chemical structures. However, in
the following cases the desirability of introducing chemical structural formulae should be specifically considered:
(a)
When the numbering of ring atoms in cyclic compounds is inconsistent in practice, because, for example,
two different systems of chemical nomenclature are applied.
(b)
system.
When a group covering cyclic compounds contains subordinated groups referring to the numbering
(c)
When a compound is indicated by its commonly used name which does not provide adequate information
on the structure of the compound.
[Annexes follow]
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Date: September 1999
HANDBOOK ON INDUSTRIAL PROPERTY INFORMATION AND DOCUMENTATION
Ref.: IPC Revision Instructions
page: 5.2.3.6
ANNEX I
POLICY FOR THE IPC REVISION WORK
POLICY FOR THE IPC REVISION WORK
DURING THE SIXTH REVISION PERIOD (1994-98)
adopted by the IPC Committee of Experts
(see document IPC/CE/XXII/11, Annex III)
The following seven policy statements should form the basis for the IPC revision work during the sixth revision
period (1994-98):
1.
Revision of the IPC, in conformity with the Strasbourg Agreement Concerning the International Patent
Classification, is needed, in order to enable efficient searches to be carried out, and this revision should
be carried out in the light of the conclusions reached by the IPC Committee of Experts (see document
IPC/CE/XV/5, subparagraphs 20(a) and (b)), i.e.:
(a)
The further development of the IPC must continue—even though an acceptable basic
scheme now exists—since the enormous influx of new patent documents each year will necessitate
revising areas of the IPC that relate to already existing technologies. If the development of the IPC in this
respect were to be discontinued, many offices would have to develop the IPC on the national level, and
the value of the IPC as a universal instrument for classification and searching would be diminished. Such
retrogression is not considered acceptable, in particular in view of more than 70 industrial property offices
throughout the world using the IPC, and the increased use of the system by industry and other patent
information users.
(b)
The main goal of the further development of the IPC should be to improve the IPC as a
universal search tool. The IPC should not be limited to cater for the searches mentioned in paragraph 2
of the Guide to the IPC, but should provide also for those searches referred to in paragraph 3 of the
Guide.
2.
Each revision request should be selected on the basis of the criteria currently agreed upon by the PCIPI
Executive Coordination Committee.
3.
When revising a given area of the IPC, every possible solution for improving that area as a search tool
should be considered, taking into account the particular search needs in the area.
4.
Care should be taken so that overlapping classification concepts are not created.
5.
Any indexing scheme introduced should be associated with an adequate classification scheme.
6.
Revision of the IPC which would change its basic structure should not be undertaken without good
reason, for example, in order to accommodate new technologies, to avoid overlaps, etc.
7.
If existing commercial databases that are readily available can meet the search needs in a certain area of
the IPC, revision of that area should not be undertaken without good reason.
[Annex II follows]
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Ref.: IPC Revision Instructions
page: 5.2.3.7
ANNEX II
NOTES IN THE IPC
PRESENTATION AND LAYOUT OF NOTES IN THE IPC
1.
The notes in the IPC should be categorized and presented in the following order:
(i)
Notes relating to the subject matter covered by the place in question (see also paragraph 2, below)
(a)
explaining subject matter which is covered;
(b)
explaining subject matter which is not covered;
(c)
other notes.
(ii)
Notes defining terms or expressions
(iii)
Notes drawing attention to other notes
(a)
drawing attention to notes appearing in other sections, subsections, classes or subclasses;
(b)
drawing attention to other notes appearing in the section, subsection, class or subclass.
(iv)
Notes drawing attention to other places in the IPC
(v)
Notes stating classifying rules
(a)
precedence rule;
(b)
last place rule;
(c)
multiple classification;
(d)
other rules.
(vi)
Notes relating to recommendations
(vii)
Other notes.
2.
Notes relating to the subject matter covered by the place in question, defining terms or expressions or stating
classifying rules (referred to under 1(i), (ii) and (v), above) should be presented as follows:
(a)
(b)
(c)
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This subclass covers:
–
apparatus which are not provided for in - - -;
–
the working of materials which - - -;
–
features specific to - - -.
This subclass does not cover:
–
multi-step processes, which are covered by class - - -;
–
details or accessories which form part of - - -, e.g.,- - -, which are covered by subclass - - -.
In this subclass, the following terms or expressions are used with the meaning indicated:
–
“working” covers also - - -;
–
“combined operation” means - - -.
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Ref.: IPC Revision Instructions
page: 5.2.3.8
Annex II, page 2
(d)
3.
In this subclass:
–
groups 3/00 to 7/00 are limited to - - -;
–
after-treatment of materials is classified in groups - - -;
–
subject matter relating to both - - - is classified in groups - - -.
The following model wordings of the different notes relating to indexing schemes should be observed:
Note for a class containing a subclass which constitutes an indexing scheme
“The codes of subclass - - - are only for use as indexing codes associated with subclass(es) - - -, so as to
provide information concerning - - -“
Note for an area to which a separate indexing scheme is associated
“In this - - -, it is desirable to add the indexing code(s) of - - -. The indexing
code(s) should be linked/unlinked.”
Note for an area where the entries may be used both for classification purposes and
indexing purposes (example from subclass C 08 F)
“In groups 210/00 to 297/00, it is desirable to add the indexing codes relating to additional monomeric
components, in cases where no specific subgroups defined by the said monomeric components are
present. The indexing codes, which are chosen from groups 210/00 to 238/00, have the same numbers
as the classification symbols, but a colon is used instead of the oblique stroke, and should be linked.”
Note at the beginning of each indexing scheme
“Attention is drawn to chapter IV of the Guide which sets forth the rules concerning the application and
presentation of the different types of indexing code.”
[Annex III follows]
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Ref.: IPC Revision Instructions
page: 5.2.3.9
ANNEX III
USE OF NUMBERS FOR NEW SUBDIVISIONS
1.
Subgroup numbering should, as far as possible, be limited to four digits after the oblique stroke. Group numbers
with a final 0 are not allowed, except for groups having only two digits after the oblique stroke.
2.
For the addition of further subdivisions the following use of numbers should be observed:
(i)
in the case of an existing interrupted sequence of numbering, e.g., 1/02, 1/04, etc., use for additional
subdivisions inserted between, for example, groups 1/02 and 1/04:
one:
two:
three:
four:
five:
six:
seven:
eight:
nine:
etc.
(ii)
1/03
1/027,
1/025,
1/024,
1/023,
1/022,
1/022,
1/023,
1/022,
1/035
1/032,
1/03,
1/028,
1/028,
1/027,
1/026,
1/036
1/033,
1/032,
1/03,
1/029,
1/028,
1/037
1/035,
1/032,
1/031,
1/03,
1/038
1/035, 1/038
1/033, 1/035, 1/037
1/032, 1/034, 1/036, 1/038
in the case of an existing uninterrupted sequence of numbering, e.g., 1/02, 1/03, etc., use as third digit:
for one
“ two
“ three
“ four
“ five
“ six
“ seven
“ eight
“ nine
(iii)
1/033
1/03,
1/028,
1/027,
1/025,
1/025,
1/025,
1/024,
subdivision
subdivisions
“
“
“
“
“
“
“
5
3, 7
2, 5, 8
2, 4, 6, 8
1, 3, 5, 7, 9
1, 3, 4, 6, 7, 9
1, 2, 3, 5, 7, 8, 9
1, 2, 3, 4, 6, 7, 8, 9
1 to 9
in the case of 10 or more subdivisions to be added between subsequent entries, e.g., 1/01 and 1/02, a
similar sequence should be used. For example, in case of 10 subdivisions, use the following sequence:
1/0113
1/0117
1/0133
1/0137
1/0153
1/0157
1/0173
1/0177
1/0193
1/0197
or, in case of 15 new subdivisions
1/0112
1/0115
1/0117
1/0132
1/0135
1/0137
1/0152
1/0155
1/0157
1/0172
1/0175
1/0177
1/0192
1/0195
1/0197
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Ref.: IPC Revision Instructions
page: 5.2.3.10
Annex III, page 2
3.
In this context, it is again emphasized that no relation exists between numbering and indentation of subgroups.
4.
The departure from the principle disclosed in paragraph 2, above, could be allowed in circumstances when it is
desirable to provide for the possibility of truncation of classification symbols when carrying out computerized searching.
5.
Finally, attention is drawn to WIPO Standard ST.8, which provides for the recording of IPC symbols on
machine-readable data carriers.
[Annex IV follows]
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Ref.: IPC Revision Instructions
page: 5.2.3.11
ANNEX IV
CHECK LIST
CHECK LIST FOR USE WHEN REVISING THE IPC
GENERAL ASPECTS
1.
This check list does not purport to be complete but is intended as a guide to various points which should be
considered.
2.
It should also be borne in mind that the various items listed in the check list cannot be dealt with independently
but are on the contrary highly interrelated.
3.
All wordings should be checked for clarity, possible ambiguity, uniform use of terms or expressions and
concordance between the English and French versions of the IPC. In addition, attention should be paid to Chapters II
and VI of the Guide.
4.
Every reference and note should be checked for accuracy and necessity.
5.
A check should be made to determine whether the titles, references and notes correctly define the necessary
borderlines with other classification places in the subclass undergoing revision or in other subclasses. Special care
should be taken with the borderlines between entries determined by application and entries determined by function.
6.
A check should be made to determine whether different technical subjects of inventions, e.g., products,
processes or apparatus for making same, are clearly defined.
7.
If local classification rules exist (e.g., last place rule), there should be a check to determine whether they are
clear and unambiguous.
KINDS OF REVISION
Subclass Revision
Consideration should be given to the following questions:
1.
Whether the scope of the subclass is clearly defined; particular reference being given to:
–
subclass title
–
notes
–
references in subclass title
–
class title with references and notes.
2.
Whether the division into main groups provides useful search concepts.
3.
Whether there is other subject matter falling within the scope of the subclass which is not
provided for or is not specifically referred out.
4.
The existence or necessity of residual group(s), function-oriented group(s) or “details” group(s).
5.
Whether each main group falls within the scope of the subclass title.
6.
The possible overlap between main groups.
7.
The breakdown of the subclass into subdivisions with guide headings.
Group Revision
Consideration should be given to the following questions:
1.
Whether the scope of the group is clearly defined; particular reference being given to:
–
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group title
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Ref.: IPC Revision Instructions
page: 5.2.3.12
Annex IV, page 2
–
notes
–
references in group title
–
class and subclass titles with references and notes
–
references in guide headings.
2.
Whether the division into subgroups provides useful search concepts.
3.
Whether each subdivision falls within the scope of its superior subdivision.
4.
The possible overlap between subgroups.
5.
The accuracy of the hierarchy of the subdivisions.
6.
Whether the number of documents and the activity is sufficient to justify the existence of every
group. Each new group should contain as an average 100-150 patent documents from the PCT
minimum documentation (with one document per patent family).
[End of Annex IV]
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Date: September 1999