Folding Attic Stairs Ltd v The Loft Stairs Company Ltd & Anor (Rev 1)

This is a patent case, and it is not an easy one. 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?

This case is about so-called folding attic stairs and how they are manufactured.

Many of the older houses in the British Isles have roof voids that are not supposed to be used for human habitation but which contain useful storage space. Therefore it is quite common to install loft ladders to provide access. Most of those ladders are of the sliding or telescopic sort and they are made of aluminium.

We are concerned with a different kind: namely a folding stairway, typically made of wood, and somewhat more expensive. Such a stairway, when not in use, is folded up and nested in a storage space just above the trapdoor in the ceiling ope. ‘Ope’, by the way, is a perfectly respectable if unusual noun, and it means an aperture or opening in the structure of a building.

The general idea is conveyed by the above image¹. It can be seen that there are three² ladders or stairway sections connected end-to-end by hinges. This arrangement enables you to fold up the stairway after you have finished using it. The upper ladder carries the ceiling trapdoor and is permanently hinged to a load-bearing frame in the ceiling ope. It can also be seen that there is a pair of folding metal arms, springbiased to keep the stairway in its stored condition; they also prevent it from falling down too forcibly when you lower it for use.

The metal arms at one end are pivoted to the ceiling ope frame; at the other, to the sides of the top ladder. If you look more closely, you can see that, to be more precise, the lower ends of the metal arms are pivoted to angle brackets. It is the angle brackets that are secured to the sides of the top ladder, but also to runners forming part of the ceiling trapdoor. I must stress that for the purposes of this case the above counts as an illustration, and nothing more: it may or may not have been prior art, but I am not presuming that it was.

The Claimant has a factory in County Galway, Ireland. Its moving spirit is Mr Michael Burke. About 25 years ago Mr Burke was approached by a compatriot who had been living in America and had brought back a set of folding stairways; he needed to have it repaired. On making enquiries Mr Burke discovered that there was no Irish company that made folding loft stairs and perhaps one English company. Mr Burke appreciated that there was a gap in the market and so he started the Claimant company. It makes and supplies folding stairs under the brand name “Stira”. The company claims to be unusual because it also installs those stairways itself, or a lot of them anyway. The “kit” from the factory comes complete with folding stairway, folding metal arms, ceiling ope frame with springs, and trap door.

For present purposes there have been two versions of Stira. The first, referred to in this case as “old Stira”, was sold in large numbers for many years. It is cited as prior art in this case. It was not unlike the product illustrated above. The new version is said to be the subject of the patent in suit. I believe that about 18,000 sets of old Stiras had been sold before the patent in suit was applied for on 5 November 1996.

The Defendant company used to do business with the Claimant. It used to buy Stiras and import them into the UK and install them. The Defendant company is owned by Mr Michael Heraghty (the Second Defendant) and his wife, but it is Mr Heraghty who makes all the decisions. The parties fell out for common business reasons. Mr Heraghty thought his company was being charged too much and so it could not make a decent margin. Mr Burke thought it was a slow payer. Anyway, there came a time when the Defendant company stopped buying Stiras and made a version of its own. The Claimant sued for infringement of patent and for infringement of unregistered design right. It did not pursue the latter claim before me.

There are a lot of old houses in the British Isles and the spacing between ceiling joists may vary quite a lot from house to house, perhaps according to the whim of the original builder. So ceiling opes comes in quite a range of widths. (Lengths do not matter so much. The ceiling plaster can easily be cut or made good as desired.) Therefore the supporting frame for a folding stairway has to be made to match the load-bearing joists that help to define the ceiling ope.

When Mr Burke looked into this he found that he would have to manufacture supporting frames in five different widths (22 to 30 inches, as measured at the ceiling trapdoor³). It would have been too expensive to manufacture ladders in five different widths too. So Mr Burke settled on a standard ladder width of 16 inches and he accommodated the difference by bending the metal support arms.

If the disconformity was small the metal arms would not have to be bent much.

With the benefit of hindsight it may seem something of a bodge to bend the arms to accommodate the disconformity. But a manufacturer setting out to make these folding stairs might not appreciate how much wear and tear some customers were going to impose on the arms. Some people may ascend into their loft maybe once a year to store miscellaneous junk. I believe that non-permanent stairways are not permitted for lofts that have been converted for human habitation, but in practice there may be a grey area. For all that I know, some people may go up nearly every day – maybe they keep a computer there and use the space as an informal home office or a den for young people, and so on. Some may ascend with caution, other rumbustiously. It is conceivable that building regulations may have changed or their application relaxed over time.

Because the Claimant company not only made but installed these folding stairways, it got feedback from its customers. After a time it was noticed that some customers were complaining that the metal arms failed. This was because there was too much strain and wear being imposed on their pivots. (The arms have pivots because they need to fold, of course.) This problem did not occur on the narrower designs.

The problem was caused by the fact that the arms on the wider designs were “leaning in”. (Think how much worse it is to carry two heavy suitcases if your arms do not hang straight down.)

Mr Burke told me that his company was in a unique position to appreciate this problem because, unlike others, it saw to the installation of the product and got plenty of feedback.

In about the year 1995 the Claimant was applying for ISO 9002 accreditation. This was an international standard, and it applied to the business, and not the product. In order to qualify, the company had to examine its manufacturing procedures so as to ensure that they were effective, properly documented, and were kept under review for defects, corrective actions and improvements. It was then appreciated that most complaints were derived from failed metal arms or their pivots. (I must say I am a little surprised that it took an ISO accreditation to bring the fact home. I should have thought that there would be fitters who would be called out to repair defective arms and they would report back to management. Still, I suppose that one object of an ISO accreditation is to get rid of a not uncommon corporate habit: burying your head in the sand, if such habit there was.)

Another problem that was appreciated was that there was a production bottleneck in the making of old Stiras. I need not explain the bottleneck much because the old process (as opposed to finished Stira itself) was not pleaded as prior art nor was it shown that it had been made available to the public or had been in use elsewhere. However elimination of the bottleneck led to a change in the design of the product. Because old Stira is cited as prior art against the patent in suit I must describe this aspect.

A simple ceiling trapdoor consists of a sheet of plywood⁴ backed by a flat wooden frame to keep it from warping. In old Stira this flat frame was secured to the face of the stairway, being sandwiched between it and the plywood sheet. As I see it, this frame did not have much of a load-bearing function, but it served as a spacer to afford extra “toe-in” room for the user. On each side of the stairway there was an Lshaped angle bracket that connected not only to the side of ladder but also to this frame. (The lower ends of the metal support arms were pivoted to the angle bracket.) The production bottleneck, such as it was, was this. Because the frame was flat and relatively thin, its four pieces were glued or screwed together in place, and not at a separate workstation.

This was deemed to be less efficient and so the frame was redesigned. Instead of being made of flat pieces of wood, the two side pieces were made thicker (i.e. they stood prouder) so that they could be rebated, to connect to the end pieces. This enabled the frame to be assembled separately. I shall call this new frame “the inner frame” to distinguish it from the outer frame i.e. the frame in the ceiling ope in and immediately above which the contraption nested when stowed away.

The decision was also made to pivot the ends of the metal support arms to the long sides (side beams) of the inner frame, which were now load-bearing beams, instead of to angle brackets attached to the sides of the ladder.

This new design had a bonus – though Mr Burke did not realise it for some time. The bonus was that the width of this inner frame could easily be varied in the course of manufacture to take account of the customer’s ceiling ope width, instead of needing to bend the metal arms. All you had to do was to vary the length of the end beams of the inner frame. In other words, the disconformity problem, previously sought to be tackled by bending the metal arms, was exported to a different part of the apparatus where it could easily be accommodated during manufacture and where it would do no harm.

The patent in suit (GB 2319051) concerns a process for manufacturing a folding stairway. It has an introductory section and I shall quote it:

That is, in general terms, a description of “old Stira”. Then the patent describes the problem, as follows:-

Figure 4 of the patent shows how the topmost ladder 30 of the stairway is secured to the outer frame 6 in the ceiling ope.

On page 7 of the patent the advantage is stressed. It says

Claim 1 of the patent is not for a folding stairway, but for “A process for manufacturing a folding stairway …” A patent must be read through the eyes of a person skilled in the art and in the light of what was common general knowledge at the time. So I shall consider those matters before examining Claim 1 in any further detail.

Although the woodwork described in the patent could probably be made without difficulty by a good amateur carpenter, the document is not addressed to him. In my judgment it is aimed at one who has a factory or workshop that can fulfil numerous orders. The amateur would not be troubled by the problem the patent aims to solve. He need not worry that ceiling joist spacings can vary from house to house; he just cares about his own house; and he could make his stairway width to correspond to the joist spacing in his ceiling. The patent is addressed to a factory that cannot or does not wish to afford that luxury, because it would be too expensive to manufacture stairways in a variety of widths.

In short, then, I hold that this is not only a patent for a process for manufacturing folding stairways, but for doing it on a repeat basis⁵. I infer this from the problem that the patent identifies (see paragraph 25 above) and the advantages of the solution it propounds (see paragraph 27). When this point is grasped some of the problems that beset this case will be seen to fall away.

The state of the art is all the knowledge in the world that had been made available to the public before a given date. Knowledge is considered to have been made available to the public if even one person was free in law to access it and use it as he pleased. Knowledge may be imparted in a document, by word of mouth or by ocular demonstration.

It follows – and is relevant to what I must address later in this judgment – that if a document is placed on the shelves of a public library then everything in the document is considered to be part of the state of the art. This is so even if it was utterly obscure and nobody bothered to consult it really. There is no doubt about the law. It sounds like a harsh doctrine, but there must be a bright-line rule. The point is that the public had the right to consult the document. Likewise if a product is exposed to view in a public place e.g. a street, where persons skilled in the art might examine it and understand its mode of operation, it is no answer to say that for aught that we know no skilled person did examine it in fact. The knowledge thus becomes part of the state of the art.

Common general knowledge is quite different. It is what people skilled in the art actually do know, or ought to know, provided that knowledge is regarded as sound. Common general knowledge is not a phrase used in the Patents Act or the European Patent Convention. It would be difficult to define the person skilled in the art in this case, or the common general knowledge, because so far as I know there is no recognised profession or calling of designing folding attic stairways. At the date of the patent nobody seems to have done it in the British Isles except the Claimant and perhaps one other company. There must have been one or more companies in America, I suppose. It is unfair to define an art too narrowly, or else you could imagine absurd cases e.g. “the art of designing two-hole blue Venezuelan razor blades”, to paraphrase the late Mr T.A. Blanco White. Then you could attribute the “common general knowledge” to that small band of persons who made those products and say that their knowledge was “common general knowledge” in “the art”. That would have the impermissible result that any prior user no matter how obscure could be deemed to be common general knowledge, which is certainly not the law.

However it does not make much difference in this case, because the amount of special knowledge that is required to understand the patent in suit is not great. I would identify the person skilled in the art as one who has practical experience as a manufacturing carpenter, assisted by a metal fabricator. At the date of the patent (1996) this person or team would be vaguely aware of folding stairways in general terms, at most. The actual construction of old Stira, while known to many customers, was not common general knowledge in the art, in my judgment.

Expert evidence was given for the Claimant by Mr Paul Thorneycroft for the Claimant and Mr Roger Galpin for the Defendants.

In Alan Nuttall Ltd v. Fri-Jado UK Ltd [2008] EWHC 1311 (Pat) I said, largely quoting from Jacob LJ:

To that I would add this: although it is inevitable that when an expert is asked what he would understand from a prior document's teaching he will give an answer as an individual, that answer is not as such all that helpful. What matters is what the notional skilled man would understand from the document. So it is not so much the expert's personal view but his reasons for that view - these the court can examine against the standard of the notional unimaginative skilled man. There is an analogy here with the well-known Bolam test for professional negligence - what matters is not what the individual expert witness says he personally would have done, but whether the conduct said to be negligent falls short of what a reasonable professional would have done.

Thus in weighing the views of rival experts as to what is taught or what is obvious from what is taught, a judge should be careful to distinguish his views on the experts as to whether they are good witnesses or good teachers - good at answering the questions asked and not others, not argumentative and so on, from the more fundamental reasons for their opinions. Ultimately it is the latter which matter - are they reasons which would be perceived by the skilled man?

But just because the opinion is admissible:

Because the expert's conclusion (e.g. obvious or not), as such, although admissible, is of little value it does not really matter what the actual attributes of the real expert witness are. What matters are the reasons for his or her opinion. And those reasons do not depend on how closely the expert approximates to the skilled man.

The technology in this case is not such that it requires much expert explication, on the whole.

Unfortunately, I found that Mr Galpin’s evidence was motivated to a considerable degree by hindsight. It may not have been his fault personally; perhaps his instructions set him down a road where it was more or less inevitable.

Claim 1 of the patent reads as follows (the emphases are mine):

That is an awfully long claim, but I can précis it to ease understanding. What is claimed is a manufacturing process for making folding stairways in which you