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Removing unwanted features from a patent claim – is the EPO getting stricter?

20th Jun 2017

The EPO has long been famous for its strict approach to added matter. The basic requirement for amendments is set out at Article 123(2) EPC: “The European patent application or European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.”

There is nothing unusual in having such a provision – 35 USC § 132 says “No amendment shall introduce new matter into the disclosure of the invention” – but what is unusual is the strictness of the EPO’s approach. This means that, amendments that would be permitted at the USPTO are routinely not permitted in Europe.

For some years now the main test in Europe for whether an amendment complies with Article 123(2) has been that any amendment can only be made within the limits of what a skilled person would derive directly and unambiguously, using common general knowledge, from the application as filed. This test has become known as the ‘gold standard’ in EPO practice.

At the same time, another test has developed in EPO case law: the three-point essentiality test. The EPO’s Guidelines for Examination, which examiners are obliged to follow, sets out the test as the following:

“The replacement or removal of a feature from a claim does not violate Art. 123(2) if the skilled person would directly and unambiguously recognise that:
(i) the feature was not explained as essential in the disclosure;
(ii) the feature is not, as such, indispensable for the function of the invention in the light of the technical problem the invention serves to solve; and
(iii) the replacement or removal requires no real modification of other features to compensate for the change.”

This test is commonly used by applicants to remove an unwanted and unnecessary limitation from a claim that is not needed to ensure novelty and inventive step, or to introduce a new feature into a claim where said new feature is an intermediate generalisation of a more specific disclosure in the application as filed.

While the essentiality test is not applicable in all circumstances, it can sometimes be easier to persuade an EPO examiner that an amendment meets the three steps of the essentiality test than that an amendment is directly and unambiguously from the application as originally filed. Perhaps this is because of the 1-2-3 structured nature of the test, whereas it can be harder to decide between what is derived directly and unambiguously and what is derived more indirectly or ambiguously. Either way, it might have in the past been used to mitigate against the EPO’s strict approach to amendments.

But this is where the Boards of Appeal come in, with their recent decision in case number T1852/13.

The applicant had filed a divisional with claims that omitted a feature that was included in the claims of the parent. While the omission of the feature on filing of the divisional was not itself an amendment of an application, divisionals are also not allowed to include subject-matter extending beyond the content of the parent application as filed, and so the same tests apply for whether the applicant was permitted to omit the feature from the claims. When the EPO examiners refused the application on the basis that the omission of this feature extended beyond the content of the parent application, the applicant appealed.

As part of the appeal, the applicant argued that the removal of the feature did not extend beyond the content of the application as filed using the essentiality test.

The Board of Appeal had to decide if it agreed with the applicant or not. In the final decision, the Board of Appeal reviewed the history of the essentiality test, and case law ever since its origin either in favour of or in opposition to the test. By the end of its review the Board of Appeal had decided that the essentiality test is not compatible with the ‘gold standard’.

In particular, the Board of Appeal concluded that the essentiality test should no longer be used.

In view of the divergent case law regarding the essentiality test, the applicant also requested a referral to the Enlarged Board of Appeal.

While the Board of Appeal recognised that a referral to the Enlarged Board of Appeal would lead to improved clarity and uniform jurisprudence in this area, it felt that it could not make the referral in this case.

This is because the issue of law was not ultimately decisive. Despite having concluded that it should no longer be used, the Board of Appeal applied the essentiality test to the facts of this case and found the omitted feature to be essential. The ‘gold standard’ gave the same result – the skilled person would not derive the omission of the feature directly and unambiguously from the parent as filed. Thus regardless of whether the Enlarged Board of Appeal would approve or disapprove the essentiality test, the result would not affect the outcome of this particular case.

This case was bad news for this particular applicant, but what does it mean for other applicants?

Firstly, while the essentiality test was declared dead in this decision, it isn’t. Yet.

The EPO currently has 28 Boards of Appeal, each of which specialises in a particular technical field and only hears appeals in cases in its respective field. This decision that the essentiality test is no longer to be used is the decision of just one of them.

The particular Board of Appeal that issued this decision is number 3.2.05, which currently handles mechanical inventions in the printing, pressing and hydraulics field. Unless an applicant is currently pursuing an appeal in this technical field, then there seems to be no harm in continuing to refer to the essentiality test if it is helpful in making the case for an amendment. Despite the decision of this Board of Appeal, the essentiality test remains in the EPO’s Guidelines for Examination, which EPO examiners are obliged to follow. There are also numerous decisions made by other Boards of Appeal supporting the essentiality test.

Therefore, the general message for applicants should probably be to carry on as normal. Until other Boards of Appeal handling inventions in other technical fields start issuing concurring decisions, or until there is a referral to the Enlarged Board to clarify the matter, then there is no big change. If you have any questions in the meantime, come and speak to us.

This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.

Christopher Smith
Senior Associate
About the author

Would you like to know more? You can talk to Christopher Smith who will be able to help. Call +44 (0)20 7242 0901


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