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In 2012 Member States and the European Parliament agreed on the "patent package" - a legislative initiative consisting of two...

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Careful Diagnosis Needed Before Claiming A Surgical Technique

The extent to which a diagnostic method which may involve a surgical step can be protected by a patent has been addressed by the EPO Enlarged Board of Appeal in its recent Decision in case G1/07. The Decision states that a method comprising or encompassing at least one feature defining a method step for treatment of a human or animal body may not be patented. Surgical steps in claims are to be avoided, if necessary by disclaimer.

Many patent systems have a provision preventing patents being used to interfere with the manner in which a medical practitioner carries out a medical activity. In some jurisdictions, such as the US, patents may be granted but medical practitioners are excluded from infringement. The European Patent Convention addresses the issue by an exclusion to patentability for "methods of treatment of the human or animal body by surgery or therapy and diagnostic methods practised on the human or animal body".

We first discussed case G1/07 in our Autumn 2009 edition of Patent issues. It relates to a method of diagnosis that involved a surgical step. "Surely a double exclusion?" you may ask. Not necessarily, because diagnostic methods are indeed patentable so long as they relate only to the collection of data from which a diagnosis may be made, not the subsequent steps of making the diagnosis (Enlarged Board Decision G1/04). 

Here we have a case of a magnetic resonance imaging (MRI) technique (mere collection of data that might well be patentable) but it involves introducing an agent (polarized 129Xe) into a particular region of a patient's body. For some regions of the body the polarized 129Xe is introduced without the need for surgery (mere inhalation), but the specification mentions the possibility of injecting the agent into the heart. The Applicant filed various method claims, all specifying a step involving delivering polarized 129Xe gas into the patient's body. 

Because the claims encompassed a surgical procedure, i.e. injecting polarized 129Xe into the heart, the responsible Technical Board of Appeal referred the following question to the Enlarged Board:

Is a claimed imaging method for a diagnostic purpose excluded from patent protection as a "method for treatment of the human or animal body by surgery" if it encompasses a surgical step but such a step does not per se aim at maintaining life and health?

The Enlarged Board said there is no rule of law which states that exclusions from patentability in the EPC must be construed narrowly. The EPC should rather be interpreted "in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose". If a method claim encompasses at least one feature defining a physical activity or action that constitutes a method step for treatment of a human or animal body by surgery or therapy it falls under the exclusion. (All the more so if it positively comprises such a step.) The term "treatment by surgery" is not necessarily confined to surgical methods pursuing a therapeutic purpose but does not necessarily encompass safe routine techniques, even when of an invasive nature, as this would go beyond the purpose of the exclusion.

The Enlarged Board confirmed that an invasive step such as in the referred case did indeed constitute "treatment by surgery", because:

  • It represents a substantial physical intervention on the body which 
  • requires professional medical expertise to be carried out and
  • entails a health risk even when carried out with the required professional care and expertise.

Beyond this, the Enlarged Board declined to address in further detail how "treatment by surgery" should be interpreted.

Accordingly, the claimed method was excluded from patentability because, when carried out, maintaining the life and health of the subject was important and it encompassed an invasive step in accordance with the above criteria.

Would a disclaimer save the claims?

In principle the Enlarged Board ruled that disclaiming the surgical embodiments was allowable but that the overall patentability of any such claim depends on all the requirements of the EPC and the usual conditions for the allowability of disclaimers set out in Decisions G1/03 and G2/03 (see box overleaf). Similarly, the Enlarged Board ruled that, in principle, a claim could be amended to omit a surgical step but that this amendment would also need to satisfy all the requirements of the EPC.


We expect the EPO to be strict in examining patent applications for inventions associated with surgical procedures. The key question is likely to be whether the surgical step is an essential element of the invention. This of course raises the old question of what is "the invention". In Europe, this is probably best answered by considering the test for an inventive step.

Under the problem-and-solution approach to the assessment of inventive step as used by the EPO, an inventive step involves a solution to a technical problem which results in a new and unexpected technical effect. Accordingly, for any new system the first step is to identify novel features which may satisfy the requirement for an inventive step. For these novel features, there are three different scenarios:

(1)    The novel feature does not involve surgical step;
(2)    The novel feature may involve a surgical step; and
(3)    The novel feature must involve a surgical step.

In scenarios (1) and (2), it should be possible to avoid or overcome a "treatment by surgery" objection with a well-drafted specification. Particular care should be taken when drafting the specification to identify the technical problem being addressed and the solution to that technical problem. Care should also be taken not to include any wording which may imply that a surgical step is either essential to the solution or may form part of the solution. In scenario (2), care should be taken to give examples not involving a surgical step and to provide basis for a disclaimer in case that should be necessary. 

In scenario (3), patent protection will be difficult to achieve. Nevertheless, given that the Enlarged Board has suggested that the term "treatment by surgery" may not cover safe and routine invasive techniques, thought should be given to different ways of performing the surgical step and whether it is arguable that any of those ways does not constitute "treatment by surgery".