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With one of the strongest life sciences patent teams in Europe, we’ve always played an active role at the EPO – and in some of the most important legal decisions it has decided. In this series, we're reviewing the ones we feel are most memorable.

Case 2 – T 0099/13 (EPO Board of Appeal, 14 January 2016)

The European Patent Office (EPO) approach to added subject matter is known across the world to be notoriously strict and is a common source of frustration for applicants. This ruling, in which Mewburn Ellis represented the patentee, saw the court appreciate some subtleties.

The claims in T 0099/13 concerned a liquid formulation of an antibody, with a kinematic viscosity of 50 mm2s-1 or less at 25⁰C.  Viscosity is highly dependent on temperature, and the disputed point was whether the specified temperature (“at 25⁰C”), as introduced during prosecution, found basis in the description.


First instance finding

Under Article 123(2) of the European Patent Convention (EPC), a European patent or application may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed. Under this practice, an amendment is only allowable if it meets the so-called “gold standard” of being directly and unambiguously derivable from the application as filed. At first instance, the opposition division sided with the opponents and did not view the temperature as derivable. This meant that the claim violated Article 123(2) EPC.


Holistic approach was appropriate

On appeal, the patentee, which was represented by Mewburn Ellis, argued that the opposition division had taken an overly artificial view of the content of the application as filed, and that a more holistic approach to disclosure was appropriate. The Board agreed, noting that the assessment of the requirements of Art. 123(2) should be done on the same basis as for all other patentability issues (e.g. novelty and inventive step), in other words from the standpoint of the same “skilled person” on a technical and reasonable basis.  

In this case, the “skilled person” – a technician in the field – would appreciate that the specified viscosity would be met at the temperature of use of the formulation. The description specified that 25⁰C was preferred, and the viscosity measurements were performed at this temperature in all examples but one (which otherwise fell outside the scope of the claims). As a result, the formulation temperature of 25⁰C was directly and unambiguously derivable from the description. To view the disclosure otherwise would require an artificial and overly semantic construction.

Contrary to the received wisdom that exact, literal wording in the description is required, T 0099/13 demonstrates that the EPO approach added subject matter is more nuanced. This will be welcome news to applicants and agents alike.

Find the decision datasheet here.

This blog was drafted by Andrew Tindall

Katherine is in our life sciences patent team and has experience in the biotechnology, pharmaceutical and Medtech sectors. Her work includes nucleic acid and protein therapeutics including antibody-based therapeutics, drug delivery and ophthalmic devices, diagnostic and prognostic techniques and metabolic engineering. Her clients include individual inventors, start-up companies, universities, research institutes and large companies. Katherine represents clients in a number of multi-party opposition and appeal cases before the European Patent Office.

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