No ope for folding ladder infringer

Mr Peter Prescott QC, sitting as deputy judge in the Patents Court, issued his judgment earlier this week in the matter of Folding Attic Stairs Limited v The Loft Stairs Company Limited. The names of the imaginatively-titled companies involved may give the reader a little clue as to what the case was about (see picture, right, an example of folding stairs available from Memphis Folding Stairs).

A dispute between the parties arose after the defendant (LSC) fell out with the claimant (FAS) over money, and started to make and sell loft stairs themselves, rather than buying them from the manufacturer. FAS then brought their patent, GB2319051, into play, claiming that LSC were infringing it.

The patent covered a small but significant development in how folding stairs for loft access were constructed. LSC argued that the patent was either anticipated by FAS's own disclosures as a result of a prototype being shown to visitors before the priority date of the patent, or was obvious over this disclosure. There was also an issue to be determined about what some of the wording in the claimed invention actually meant, namely whether the words "predetermined" and "preset" meant anything at all and, if so, whether they could be a limitation on the claimed invention. The matter of infringement was not really an issue at all, presumably because LSC were making stairs to FAS's own design (design right was also briefly mentioned, but did not feature). The judge put the issues as follows:

"Two points of difficulty are these. What happens if a manufacturer allows selected members of the public onto his premises, not on terms of confidence, where they can see a product that is still under development, but they are not experts and do not understand its significance – could that invalidate a patent afterwards applied for? And what are we to make of the phrase "spaced a preset distance" in the patent claim – are words of intentionality allowed?"

The patent covered a manufacturing process for the folding stairs in question, rather than the stairs themselves, a key feature of the invention being that a part of the construction process involved allowed for a difference between the width of the stair portion and a width of a frame made to fit an existing opening in a ceiling (termed an 'ope' in the patent, hence the appalling pun above). Because it was impractical to make stairs of various widths to fit a known range of sizes of ope, a single width stair was used with a modification to how the folding metal arms were connected to the frame, made during manufacture of each set of stairs. The feature allowing this involved the use of an inner frame positioned a "preset distance" inwardly from the outer frame, which was made to fit the available size of ope. This implied some intention on the part of the person performing the invention, which gave the judge some difficulties in construing the claimed invention.

"I must say I have seen 'predetermined' and 'preset' in granted patent claims on occasions too numerous to recall, and the experience of Jacob LJ in patent cases is a fortiori. Therefore I do not believe his stricture applies to the word "predetermined" as such. I do not have a convenient means of searching the claims of granted European patents, but as an exercise I have looked at the online database of the United States Patent Office, where the text of claims granted since 1975 is searchable electronically. I expected to find many patents with the word 'predetermined' in one or more claims. Even so, I was astonished. There are more than 658,000 such patents.

While I have not been able to perform a similar exercise for the European Patent Office, I have no doubt that it is accepted EPO practice to allow it to be used, provided the criterion that enables it to be understood is sufficiently clear. There are numerous decisions of the Boards of Appeal where the word 'predetermined' was used in the claims and no objection was taken to it, provided the purpose was clear. (There are too many to read through, but see e.g. decisions T 1241/04 and T 0463/01). Indeed in the 2007 edition of the Guide for Applicants, Annex III, available on the EPO website, there is a model patent application – as if to say, "Now, let us show you the right way to do it" – with the word 'predetermined' in claim 1. The usage can also be found in guidance to candidates for the European Qualifying Examination in the form of acceptable examination answers, also published on that website.

I am unable to accept a contention that, in the context of this patent, 'predetermined' or 'preset' is meaningless and of no effect. A reader skilled in the art would think the patentee was using it in order to try to tell him something; and he would work out the purpose by reading the patent as a whole."

The judge then found that the correct meaning of the claimed invention could be found, the key to this involving noticing that the claim was for a process for manufacturing folding stairways on a repeat basis, and that the purpose of setting the inner frame a certain distance away from the outer frame had to be taken into account. The scope of the claimed invention, although narrow, could therefore be determined.

On the matter of validity, the arguments raised by the defendent involved a prior disclosure of a prototype on the manufacturer's premises. The manufacturer had allowed members of the public, including an Irish minister and a press photographer, on to their premises before the patent was applied for. A prototype of their folding stairs was seen and photographed, and a picture appeared in the Irish press, showing the managing director of the company with the prototype in the background. The question was then whether the undoubted disclosure of the prototype was in fact an enabling disclosure of the invention to the public. The judge said:

"It is clear law that, if this test unit had been in a public place e.g. a street, where anyone might have stopped to examine it, its design would be considered to have been made available to the public. In Lux Traffic Controls Ltd v. Pike Signals Ltd [1993] RPC 107, 132-135 prototype traffic lights were given field trials. It was not proved that any member of the public – much less an expert in traffic lights – stopped to deduce the novel modus operandi. Even so it was held that the new idea was made available to the public. The principle is the same as the obscure book on the shelves of a public library that nobody consulted in fact. The law must draw the line somewhere, as I have said, and it does so by adopting the rule that inasmuch as the public had a right to be there, they are deemed to have had the right to access the information. In the same way, if it is proven that all sorts of members of the public could enter private factory premises, no obligation as to confidentiality being imposed, the law will consider that whatever could be seen there has become part of the state of the art. In those circumstances the law cannot start speculating about who did or did not see the thing.

In our case, however, the test unit was not in a public place at all and it was available for viewing by a small and defined class: the Minister and the photographer. They were not persons skilled in the art; and there is no evidence that they were interested in manufacturing folding attic stairs – it seems unlikely – nor that they manifested any interest in the test unit (which was not in the main part of the factory). Even so, urges Mr Davis for the Defendants, they were free to examine the unit if so minded, they were free impart to anyone in the world whatever recollection they had of it, and so its construction must be considered to have been made available to the public."

The judge in the end came down on the side of the claimants, finding that the claimed invention was not disclosed to the public, in part because, on the balance of probabilities "if some officious person had stopped them on the way out and asked them to describe the test unit, it is unlikely that they would have been able to describe the presence of an inner frame with side beams spaced from the sides of the ladder" (para 89). There was no reason why a normal human being, not interested in the manufacture of folding ladders, could care less. Even if he was wrong on this point, the judge considered that the claimed invention, because it was a process for manufacture, was also not obvious in light of such a disclosure. The patent was then found to be valid and infringed.

The IPKat thanks Mr Prescott for yet another well-written and clear judgment, which has made him think a bit more about what words should and should not go into a patent claim. Just because a word such as 'predetermined' is used in lots of granted claims, and is apparently approved by the EPO, does not mean that it is ideal or clear in all circumstances. As with the dreaded word 'means', some words can be used as lazy shortcuts to avoid describing what the invention actually is, or at least leaving a claim sufficiently vague that things other than what were being thought of at the time of drafting might possibly be covered. This does not, however, make things easy (or cheap) once a patent has been granted. The IPKat thinks that it is still preferable, wherever possible, to use words that have a straightforward meaning in themselves and which do not need the skilled person's motivation to be brought in to give them meaning. This does not mean that the claims need to be narrow, just that the drafter should perhaps think a bit more about the invention before setting out what it is.