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Innovators in advanced materials can face an uphill struggle to get suitable patent protection at the European Patent Office. Matthew Smith explains.

When a useful new material is made, by whatever means, for whatever purpose, the intellectual property surrounding that should be protected. This is true for all inventions, but in the field of materials we are presented with some special challenges. These are particularly apparent before the European Patent Office (EPO).

New materials are vital in addressing the problems we face individually as well as societally. But as materials become more complex, refined, and diverse, our systems for protecting such innovations must also change, evolve and improve to suit the modern technological landscape.

Patent claims can primarily be split into two types: ‘item’ (product or apparatus) and ‘activity’ (use, method, process). Ideally we want protection of both types: to protect, for example, not just our new material but also uses of it and ways of making it.

The EPO requires that we define a product in terms of its technical features (physical characteristics). This works well for a ‘conventional’ product—a widget with part ‘a’ connected to part ‘b’.

What do we do when our product is a material? In the best case scenario, we can recite or explain the structural features which define it—particles of X, dispersed homogeneously in Y, for example.

However increasingly we face situations where this is simply not possible. We cannot say, or do not know, the microstructure of our new material—perhaps it is subtly variable through its bulk; perhaps a purely structural definition would be too narrow to capture the true scope of the invention. Composites and particularly alloys are just two areas where this is often a concern.

This gives us two options. First, a process based definition of the material by reference to the way in which we have made it. Second, a parameter based definition of the material by reference to its key performance properties and characteristics.

A process-based definition

This is what is commonly referred to as a product-by-process claim. These claims define a product in terms of the process used to make it: for example, a material X, obtainable by the steps a, b, c. There are two problems here: both are somewhat swept up by an observation seen frequently in comments from European patent attorneys: traditionally, the EPO does not like product-by-process claims.

The first problem stems from a point of interpretation: the EPO considers the product-by-process claim to be directly to the product itself, and not limited by the method used to make it. That means the product itself must be novel and inventive.

Fair and reasonable on paper, sure, but in practice a major headache. EPO case law going back over 30 years places a burden of proof on the applicant. This can put us in a very uncomfortable position: having to prove novelty of the claimed product.

That generally requires experimental data reproducing prior art teachings (which is often difficult or even impossible), possibly within a relatively short time frame, perhaps six and a half months, unless extra fees are paid. Such activity can be prohibitive for small companies, who may not have resources available for such investigations. It may even prove a challenge for larger concerns, whose research and development departments are not set up to reproduce but to innovate.

While the EPO examiner does need to explain their objection to a product-by-process claim, for example by explaining why they think the products of two processes would be the same, it is not straightforward to overturn such an objection without hard evidence.

The second problem again stems from interpretation, but this time of process claims.

How so? Well, Article 64(2) of the European Patent Convention (EPC) states that the protection afforded by a process claim extends to “products directly obtained by such process”. This seemingly removes the need for product-by-process claims, and indeed the EPO often argues to that effect.

Some might say that that interpretation is not quite right. Article 64(2) of the EPC very carefully recites that protection is given to only those products directly obtained by the claimed process.

That is, the product must actually have been obtained by the claimed process. The product-by-process, on the other hand, is not so limited (when the word ‘obtainable’ is often used—using ‘obtained’ has some limiting effect in some EPO countries but not in others, although the EPO make no distinction). The product-by-process claim covers the product as obtained by any method.

Clearly this is a more useful scope. It’s also more enforceable–as a patentee, I don’t have to prove or investigate the alleged infringer’s process. Having their product is enough.

It follows from the above that product-by-process claims are not only important in their own right, they are also judged to a very high standard by the EPO.

In the field of polymers ‘product-by-process’ claims are often accepted without question. There, it is well understood that the product of the reaction between a number of monomers is somewhat unpredictable at an atomic/molecular scale—but that the product can still be useful and predictable at a macro scale.

In the future, perhaps the EPO will start taking a more similar approach with claims directed to other types of material than polymers. Denying the inventors of complex materials protection for those inventions simply because they have created, for example, a composite not a polymer seems unreasonable.

A property based definition

So a process-focused definition is less than ideal. What about the other option, a property-based claim? Sadly, things are not much better.

Let’s say we define our excellent new material as comprising components A and B, and having a thermal conductivity of X, tensile strength of Y, and a refractive index of Z.

Again we face a number of problems beyond the normal. The main one is analogous to the ‘first problem’ mentioned above: the EPO is able to place the burden of proof on the applicant, to prove that prior art materials comprising A and B do not have the properties X, Y and Z. The EPO is often strict here: no benefit of doubt can be accorded if the applicant does not provide evidence.

Certainly as a first step the EPO examiner must make some comparison with the prior art, but often it falls to the applicant to explain in detail why the claimed materials are different from those of the prior art, and often to provide experimental evidence proving that. Again, this is not always straightforward or even possible for all applicants.

Furthermore even if the objection is addressed using argument there is no particular standard to be met: we must simply ‘convince’ the examiner. What is needed to achieve that can be highly variable.

Then there is the matter of clarity. Of course the meaning of claims must be clear but the EPO has special rules for the consideration of materials’ (all) parameters in patent claims. Definition in terms of parameters is only allowable if “the invention cannot be adequately defined in any other way”—but there is no clear standard for what “adequate” means.

Parameters must be reliably measurable—in practice this often means extensive explanation of measurement methods must be included in the description, adding a time and cost burden for applicants. Further problems can arise if there are a number of different ways of measuring a property (the classic example being viscosity).

What does the future hold?

Innovators in advanced materials can face an uphill struggle to get suitable patent protection at the EPO. That is not to say it is impossible, or that applicants should be discouraged from applying. It is merely a recognition that when writing such applications we must do so with an eye for the future (including plenty of flexibility) and with a plan for success.

Having successfully obtained hundreds of European patents in this area, I know that there is usually a way through the minefield. The earlier we know it’s coming, though, the better we can plan for it!

Article originally published in IP Pro Patents.

Matthew is a Partner and Patent Attorney at Mewburn Ellis. Working primarily in the chemical and materials science fields, he has significant experience of the intricacies of the EPO. Matthew advises and assists clients with all stages of drafting, prosecution, opposition and appeal before the EPO. Many of his clients are Japanese and Chinese businesses that are seeking European patent protection. These include multinational corporations in the fields of high-performance ceramics and carbon fibre technologies, as well as pharmaceutical and cosmetic companies. Matthew also works with several research institutions and university technology transfer departments across Europe.

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