May the spirit and scope of the invention be with you

The (re-)emergence of the inventive concept in UK patent law

The English courts are increasingly turning to the notion of the “inventive concept”, as distinct from the wording of the claims, to determine the scope of protection afforded by a UK patent. Since a patent is ultimately only as good as the protection it provides, is it necessary to rethink the way we draft patent applications to help the court understand the inventive concept behind a claimed invention?

In the now infamous UK Supreme Court case of Actavis v Eli Lilly¹, which explicitly introduced the doctrine of equivalents into UK patent law, Lord Neuberger held that a problem of infringement is best approached by addressing two issues, namely:

(i) Does a variant infringe any of the claims of a patent as a matter of normal interpretation?
(ii) And, if not, does the variant nonetheless infringe because it varies from the invention in a way or ways which is or are immaterial?

He explained that issue (ii) involves not merely identifying what the words of a claim mean to the person skilled in the art, but also considering the extent, if any, to which the scope of protection afforded by the claim should extend beyond that meaning. This is bringing in the possibility of protection beyond what the skilled person in the art would have understood the patentee to be claiming on a purposive construction as established by Lord Hoffman in the earlier Kirin-Amgen case².

In dealing with the second limb (ii) of this new test, Lord Neuberger considered it was helpful to ask whether the variant achieves substantially the same result in substantially the same way as the invention, i.e. the inventive concept revealed by the patent.

Inevitably, this has led parties in subsequent cases to dispute what is the “inventive concept revealed by the patent”. In Icescape v Ice-World³, Lord Kitchin presided over a case concerning a system for cooling mobile ice rinks. He held that a cooling member for a mobile ice rink with a parallel connection between manifolds instead of a series connection, as claimed in the patent, achieved the same result in substantially the same way as the invention, when focusing on the “inventive core” of the patent. The “inventive core”, in this instance, was found to be a joint member connecting rigid pipe sections – the member is fluid tight and flexible and allows the connected pipe sections to fold relative to one another for transportation. 

Other decisions have followed⁴; in each case, a variant was considered not to be essential to the inventive concept of the patent, leading to a finding of infringement. 

It is clear we have come a long way since EMI v Lissen in 1938⁵, when Lord Russell held that “If the Claims have a plain meaning in themselves, then advantage cannot be taken of the language used in the body of the Specification to make them mean something different” and, notoriously, “What is not claimed is disclaimed”!

Extending the scope of the patent protection beyond the claims

The question that arises is how far can the language included in the body of a specification be used to steer the scope of protection of a patent beyond the normal meaning of its claims, and how can patent drafters take advantage of that possibility?  

These days, patent specifications are rarely (if ever) drafted in multiple different versions for different countries and regions.

It is commonplace to use to the same text everywhere (duly translated where necessary), especially when this is the inevitable result of the Patent Cooperation Treaty (PCT) system. 

Text may be standard but enforcement may differ

But it is important to think about how a patent will be enforced by the courts in other countries and to try and tailor the specification as far as possible to optimise the protection it gives, at least in the most important territories. Can this be helped or hindered by suggesting in the specification what the inventor considers to be the inventive concept?

In Actavis v Eli Lilly, the patent⁶ claimed a combination of pemetrexed disodium (an antifolate) and vitamin B12 for use in inhibiting tumour growth.

The alleged infringements involved diacid, ditromethamine or dipotassium forms of pemetrexed instead of the disodium salt and thus fell outside the normal meaning of the claims. 

However, the specification included several general statements like “Surprisingly and unexpectedly, we have now discovered that certain toxic effects such as mortality and non-hematologic events, such as skin rashes and fatigue, caused by antifolates, as a class, can be significantly reduced by the presence of a methylmalonic acid lowering agent as vitamin B12, without adverse adversely affecting therapeutic efficacy”. This led Lord Neuberger to conclude that the inventive concept was the manufacture of a medicament which enables the pemetrexed anion to be administered with vitamin B12.

In Icescape v Ice-World, the patent⁷ taught: “[T]he cooling elements … can be delivered in the transport position, such as folded on top of one another. Before being transported, the pipe sections and the joint members … are pressure tested for fluid tightness ... Because the longitudinal pipes have been connected to one another such that they are fluid-tight prior to assembly and retain their fluid tightness in the transport position, assembly of the ice rink can take place very rapid.”

UK courts favour detail on technical features

In some jurisdictions, there is a great reluctance when drafting a patent specification to tie oneself to any particular interpretation.

However, it is evident that in the UK courts at least, giving some indication of what the inventor considers to be the inventive concept or inventive core of the patent might assist the courts in finding infringement under the doctrine of equivalents, even where the alleged infringement falls outside the wording of the claims when purposively construed. 

To optimise the scope of protection afforded by a patent in the UK therefore, it is worth giving consideration to linking particular technical advantages or effects of the invention with particular features of the invention to show the courts which features may be varied without departing from the fundamental spirit and scope of the invention.

Further information

Next steps

• Check out the upcoming FICPI Academy of Education patent drafting courses:  The South East Asian (SEAD) course runs from 9-13 December in the Philippines. 
• In planning are FICPI courses for EuroSEAD, and the Latin American SEAD. 

How FICPI makes IP attorneys more effective

Although the fundamental concepts of patent law are universal, there are still many significant differences in the way those concepts are implemented in different jurisdictions. 

Administrative procedures of the kind provided by the Patent Cooperation Treaty make it easy for applicants to file a single application covering a very large number of territories, but there are pros and cons, and a specification prepared for one country by a local practitioner may not be optimal in other countries.  

The problem is that once the application has been filed, one is largely stuck with its contents; nothing can be added. So, it is vitally important that practitioners take account of the way patents will be enforced in other countries at the very outset when they prepare and file the first text of the application. This is not easy, and FICPI can help its members and their clients by sharing practice tips of this kind through training courses, meetings and events, and the FICPI Newsletter and Blog.  

FICPI courses provide a fantastic opportunity for students to learn from tutors from several major jurisdictions and to learn to draft with an eye on the application and granting process as well as enforcement in multiple countries.