Obtaining an EP Patent - A crash course for the US applicant #5

Claim requirements: Conforming a US-style claim set to EPO practice - Obtaining an EP Patent - A crash course for the US applicant #5

Written by Fabian Lieb

Focus: Claim requirements – Conforming a US-style claim set to EPO practice

The EP standpoint

The European Patent Convention (EPC) contains several requirements as to the type and number of claims in a claim set, which are different from US practice.

1. One independent claim per category

A first such requirement is the so-called “one independent claim per category” rule. This is stipulated in Rule 43 (2) EPC. According to this rule,

a European patent application may contain more than one independent claim in the same category (product, process, apparatus or use) only if the subject-matter of the application involves one of the following:

(a) a plurality of interrelated products, 
(b) different uses of a product or apparatus, 
(c) alternative solutions to a particular problem, where it is inappropriate to cover these alternatives by a single claim.

Hence, there are four different categories of independent claims, namely independent product claims, independent process claims, independent apparatus claims and independent use claims.

Having more than one independent claim in one of these categories is generally not allowed. The only exceptions are the three situations defined under (a) to (c) above. Further details on these exceptions can be found in the EPO Examination Guidelines1.

2. Unity of invention

A second such requirement is the so-called “unity of invention” rule. This is based on Art. 82 and Rule 44 EPC, which read as follows:

Art. 82 EPC:

The European patent application shall relate to one invention only, or to a group of inventions so linked as to form a single general inventive concept.

Rule 44 EPC:

(1) Where a group of inventions is claimed in a European patent application, the requirement of unity of invention under Article 82 shall be fulfilled only when there is a technical relationship among those inventions involving one or more of the same or corresponding special technical features. The expression "special technical features" shall mean those features which define a contribution, which each of the claimed inventions considered as a whole makes over the prior art.

(2) The determination whether a group of inventions is so linked as to form a single general inventive concept shall be made without regard to whether the inventions are claimed in separate claims or as alternatives within a single claim.

While this might at first sight seem similar to US statute and rules2, the EPO has in fact developed a different and very detailed procedure for assessing compliance with this requirement3.

3. Excess claims fees

A third such requirement is the payment of excess claims fees, which is laid down in Rule 45 EPC and Art. 2 (1) No. 15 of the Rules relating to Fees.

A patent application comprising more than fifteen claims incurs payment of claims fees for the 16th and each subsequent claim. The amount is currently 265 € per claim up to the 50th claim and 660 € per claim above that.

4. Claims with reference signs

A fourth such requirement is the inclusion of reference signs in the claims. The basis for this is Rule 43 (7) EPC:

Where the European patent application contains drawings including reference signs, the technical features specified in the claims shall preferably be followed by such reference signs relating to these features, placed in parentheses, if the intelligibility of the claim can thereby be increased. These reference signs shall not be construed as limiting the claim.

As an applicant, what should you do to conform your US-style claim set to EPO practice? 

First, you should try to reduce the number of claims to 15. This is to avoid the hefty claims fees. You can do this by using multiple dependencies, which are no problem at the EPO. You can also combine dependent claims by using terms such as “preferably”, “optionally, “in particular” and the like. You may also transfer some claims as so-called “claim clauses” to the description.

Second, if you have several independent claims in the same category, you should choose the most important one and rewrite the others as dependent claims or remove them.

Third, if your application has drawings, you should add corresponding reference numbers to the claims.


1Cf. the EPO Examination Guidelines, Part F – Chapter IV 3.2
235 U.S.C. 121, 37 CFR 1.141
3Cf. the EPO Examination Guidelines, Part F – Chapter V

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