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Appendix 2: EPI Manual Coding Criteria
EPI manual codes are normally assigned in two ways, namely:-
1 To highlight the novel aspect of an invention itself
2 To indicate significant application
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In the first case, codes will usually be assigned based on the content of the patent claims. In the second
case, applications may be derived from either the claims or the wider disclosure of the specification.
The following general points should be noted regarding the assignment of EPI codes:-
1 A patent may be selected for inclusion in EPI based on its intended use only, the actual novel
aspect being outside the scope of EPI codes. For example, the invention may relate to a novel chemical
compound of relevance to an electrical or electronic industry, such as a polymer composition intended as a
magnetic tape substrate. In such a case, only the application aspect can be conveyed by EPI codes.
2 Where an invention has no stated application, is of universal application, or a series of
applications is given which are merely standard uses for such a device, manual codes are usually assigned
to describe only the invention itself. Examples of this include a common electronic component such as a
capacitor, or a battery of a type used in a wide variety of portable devices. However, significant electrical
applications which are emphasised, or are one among several non-electrical applications, will be coded.
3 EPI manual codes are hierarchical in structure, such that an increase in the number of characters
represents a finer subject breakdown. This means that in cases where the precise details of an invention
cannot be determined with certainty, or where several code subdivisions are equally applicable, a general
manual code may be assigned. A more general code is also assigned if an appropriate sub-division code
does not exist. Thus, when formulating a search, users are advised to consider the inclusion of a more
general code in addition to finer subdivisions which are known to be relevant.
4 In many areas of the EPI coding system, in addition to codes for a product, separate subdivision
codes are provided to represent materials used in the product, their manufacture, and manufacture of the
product itself. Note that in general, the manufacture of materials used in a product is not coded as
manufacture of the product unless it is one of a number of steps in a process for manufacturing the
product as a whole. Thus, manufacture of a polymer material which can be used as a magnetic tape
substrate is coded as a tape substrate. Subsequent processing of the material, such as cutting or shaping
to form the actual substrate, is coded as substrate manufacture.
5 As explained in Appendix 1, patents are included in EPI either by virtue of patent office-assigned
IPC or by an intellectual selection process. Irrespective of the initial route by which the invention is
included, the same intellectual criteria are used to assign manual codes. However, it should be noted that
the requirements for electrical content differ between EPI classes since, as explained in Appendix 1, some
inventions are included
electrical aspect. For example, a patent in the field of instrumentation or control, included only on the
basis of its IPC, cannot be assigned for an application in X25 (industrial equipment) since the electrical
content requirements for that class are not satisfied. Conversely, an invention selected for X25 based on its
electrical content can be coded for any significant control or instrumentation content where relevant.