The decision in Adolf Nissen Elektrobau v Horizont Group, handed down by the Intellectual Property Enterprise Court at the end of last year, raises two interesting points of general relevance in patent law, particularly in relation to areas of technology which are heavily regulated. The decision provides an illustration of the fact that the skilled person’s common general knowledge is geographical in scope, and therefore what is obvious in Germany might not be in the UK. That can have consequences when it comes to finding the right expert witness to act in a patent case in the English courts. Secondly, it is a useful reminder that in the English courts, only technical obstacles, rather than commercial or regulatory obstacles, are relevant factors in assessing obviousness.
The parties are German-based competitors in the field of electric road traffic signs. Adolf Nissen sought to revoke a GB patent owned by Horizont, presumably in order to clear the way for sales of its own products in the UK. The first point of interest concerns the geographical scope of the common general knowledge (“CGK”). In English patent law, CGK is the knowledge which the skilled person, through whose eyes the patent is viewed, is deemed to bring to bear when reading the patent. The CGK is that body of knowledge which is generally known and accepted by those working in the field as a reliable foundation for further work. The CGK is territorial – the skilled person is deemed to be based in the UK, and will have the CGK of a person in the UK. This approach is to be contrasted with that adopted towards novelty and inventive step, where a document made publicly available anywhere in the world is deemed to be prior art, even if it did not (or even could not have) come to the attention of anyone in the UK.
In many, perhaps most, areas of technology, the territoriality of the CGK is not relevant, because the CGK will be the same across the world. In the field of organic chemistry, for example, the international nature of text books, journals and conferences means that the skilled chemist in the USA is unlikely to have a different body of knowledge to one in, say, the UK or Germany. In Nissen, however, the territoriality of the CGK was an important factor. That is because road traffic signage is highly regulated, and each country has its own set of applicable regulations. The regulations in Germany are not the same as those in the UK – for example, directional arrows and lane closure crosses are yellow in Germany but red in the UK. This was of particular relevance to the construction of a central term in the patent’s claims, “a mobile warning device”. The patentee’s expert witness (a German consultant with expertise in traffic signs and lighting) contended that it was a term of art, meaning a vehicle mounted sign which is in motion during use of the sign. The claimant’s expert witness, who was UK-based, agreed that a mobile warning device is one that is used when mounted on a vehicle, but disagreed that the vehicle must be in motion when the sign is used.
Although the patentee’s expert witness was not challenged in cross-examination on his understanding of the term, the judge rejected his construction, preferring that of the claimant’s expert. The judge said that “I cannot rely on [the patentee’s expert’s evidence] evidence because he is not familiar with practice in the UK and the terms used in this country”, and held that his assertion that it would be understood as a device to be used whilst moving was “an assertion without any basis of knowledge about what those in the field in the UK say”.
More generally, where an understanding of the patent and the background technology is affected by national regulations or practice, rather than by universally applicable scientific principles, the territoriality of the CGK is likely to be relevant. In such cases, parties need to think carefully about whether their chosen expert has sufficient experience of UK regulations and practice to assist the court. Other areas where such national factors could be relevant might include clinical medicine, building construction and the automotive sector, to name just three.
The other issue of interest relates to the test for obviousness. The Patents Act 1977 contains a single test – is the alleged inventive step obvious over the state of the art to the skilled person? Subsequent case law has laid guidance as to answering that question, of more or less relevance depending upon the individual facts of the case. One commonly adopted approach is to ask whether the skilled person would have regarded there as being an obstacle in the path of the alleged invention in the patent. Overcoming any such obstacle, even if it was perceived rather than real, can provide evidence of an inventive step. The nature of the obstacle, however, is critical. The judge cited Lewison J in Ivax Pharmaceuticals UK Ltd v Akzo Nobel BV  EWHC 1089 Ch: “It seems to me, therefore, that obstacles to regulatory approval of pharmaceutical products are not relevant obstacles to an obviousness attack. It is also worth drawing attention to the clear distinction … between obstacles to manufacture on the one hand, and obstacles to lawful sale on the other. Obstacles to lawful sale are not relevant to obviousness”.
The patentee sought to argue that one of the pieces of prior art relied upon by Nissen (a German Utility Model) should be disregarded because, if adapted to fall within the scope of the patent claims, it would be unsafe in use and would not meet UK regulatory requirements. Applying Ivax, the judge rejected that argument. If it is obvious, on technical grounds, to adapt the Utility Model such that it fell within the patent claims, that is the end of the matter – any issues over safety and regulatory compliance are simply not relevant in patent law. The judge decided, on the evidence, that it was obvious to adapt the Utility Model, and the patent was therefore held to be invalid on grounds of obviousness.