Inventiveness and incontinence: a barrage of cross-purpose expert evidence

The substance of Environmental Health Systems Limited ("EDS") v Synergy Health plc and Another ("Synergy") & Gravits (International) Limited & Others ("Gravitas") [2014] EWHC 1306 (IPEC) concerns obviousness of EDS's European Patent No 2 393 989 for a method of manufacturing barrage units. However, the case highlights a tension that can arise between the English approach to the person skilled in the art and the practical effect of the field of expertise chosen by the parties for their experts.

Not everyone is so concerned
about incontinence: there are those
who prefer to go with the flow ...

The method of the patent was the manufacture of water absorbent pads and their arrangement within a porous bag or sack, forming a barrage unit. It is common ground that, since about 1994 Synergy, has been making absorbent pads according to the method in the patent (by agreement with EDS until June 2011). Until 2007 these had been used solely for healthcare purposes. Gravitas sells sandbag substitutes for use in flood defences and for non-flood purposes. It was also common ground at trial that these are made using absorbent pads supplied to Gravitas by Synergy and that the absorbent pads are made according to the method described in the patent. Patent infringement was therefore alleged.  However, because of other issues raised in defence – continuing acts done before the patent's priority date (section 64 Patents Act 1977) and non-entitlement to a patent (section 72 (1)(b)) – it was decided that the whole matter could potentially be disposed of by determining the patent's alleged obviousness as a preliminary issue: whether there is an inventive step in the patented method of manufacture of barrage units from absorbent pads (which were known in the prior art for healthcare purposes, particularly for use as incontinence pads).

In the event, Judge Hacon found that by the start of 2009 the skilled person would consider absorbent pads to be at least worth trying as fillers for a barrage unit, with a reasonable expectation of success given the disclosure of sandless sandbags. Hence, there was no inventive step in the manufacture of barrage units as claimed in the patent.

But will the expert's evidence hold water?

So what's the really juicy ["Is this the right word?" asks Merpel] bit of this case? The judge was hampered in assessing the obviousness issue by the expert choices of the parties. Schlumberger Holdings Limited v Electromagnetic Geoservices AS [2010] EWCA Civ 819 is authority for the proposition that the technical backgrounds of the skilled person addressing construction and/or insufficiency on one hand, and inventive step on the other, may not necessarily be the same. Although Schlumberger does not go so far as to say that inventive step must always be considered through the eyes of a skilled person drawn from the relevant prior art, for which there is authority in the European Patent Office's Technical Board of Appeal (TBA) cases (T422/93 JALON/Luminescent security fibres [1999] EPOR 486). Hence, the judge says, there is nothing wrong with having the skilled person who is assessing construction of the claims or insufficiency also assess inventive step; if a skilled person drawn from any technical field finds the claimed invention obvious having read an item of prior art, there is no inventive step. However, absent the prescriptive approach to addressing prior art that the TBA employs, this means that the scope for the identity of the skilled person allowed by UK law can result in experts opining on completely different areas of expertise. This is what happens in this case. In fact, it happens twice:

Look, no pads!

Gravitas pleaded that the skilled person was a manufacturer of absorbent products without saying whether he came from the personal hygiene or flood defence industry, Synergy said nothing and EDS pleaded that the skilled person was interested in environmental protection with a focus on barrage units. However, upon exchanging expert reports, it transpired that EDS had decided to switch to an expert on absorbent pads in the hygiene business and Gravitas settled on an expert on flooding defences. Again, both experts were at cross-purposes.

Given that this problem can arise under the law, Judge Hacon emphasised the practice point that could have avoided the dilemma at trial:

"by the time of the CMC [case management conference] the parties' contentions in this regard (and all others) must be clear so that the court is in a position to rule on whether expert evidence may be given and to identify the technical field or fields to which that evidence will relate. The parties can then select their expert witnesses from that field or those fields. From the CMC onwards these matters should be fixed for the purposes of the trial."

In other words the issue could have been headed off at the CMC. In fact, a year on from the implementation of the Jackson reforms, the case gives cause for reflection that, further to the amendments made to CPR 35.4 in April 2013, parties are not merely required to identify the field with which the expert evidence is concerned at the CMC now, but also the issues that evidence will address. The more general practice point is therefore that consideration of expert evidence cannot begin too early in a case.

Incontinence here
Incompetence here
Intemperance here
Pee Power here

Huge thanks are due to Paul England (Taylor Wessing LLP) for leaping into instant action in order to draft this word-perfect Katnote in less time than it takes to, well never mind ...