Judgment Approved by the court for handing down Burnden v Ultraframe
(subject to editorial corrections)
Neutral Citation Number: [2005] EWCA (Civ) 867
ON APPEAL FROM PATENTS COUNTYCOURT
His Honour Judge Fysh QC
PAT 03102 & PAT 03095
Royal Courts of Justice
Strand, London, WC2A 2LL
Before :
LORD JUSTICE KENNEDY
LORD JUSTICE CHADWICK
and
LORD JUSTICE JACOB
Between :
The Burnden Group plc | Claimant/ Appellant |
- and - | |
(1) Ultraframe (UK) Ltd (2) Christopher Richardson and between: The Burnden Group plc -and- (1) Northstar Systems Ltd (2) Seaquest Systems Ltd | Defendants/ Respond-ents Claimant/ Appellant Defendants/ Respond-ents |
Mr Iain Purvis and Ms Kathryn Pickard (instructed by Messrs Addleshaw Goddard)
for the Claimant/Appellant
Mr David Kitchin QC and Mr Adrian Speck (instructed by Messrs Wragge & Co)
for the Defendants/Respondents
Hearing dates : 22/23 June 2005
Judgment Approved by the court
for handing down
(subject to editorial corrections)
Lord Justice Jacob (giving the first judgment at the request of Lord Justice Kennedy):
1. The issues on this appeal and cross appeal from a judgment of HHJ Fysh (16.9.04) were:
i) whether claim 7 of UK Patent 2,259,926 (“Scholes”) is invalid for lack of novelty or obviousness;
ii) if the claim is valid, is it infringed?
2. After hearing submissions on the issue of validity we concluded that the Judge was right to hold the patent invalid. Accordingly we so indicated to the parties and did not hear argument on the cross-appeal about infringement. We indicated that we would give our reasons for dismissing the appeal at a later date.
3. It is not suggested that this case involves any issue of principle or is likely to be of interest to anyone other than the parties. So it would not be a useful task to produce a self-contained judgment, one which is readable as a freestanding narrative. It is sufficient to cross-refer to the judgment below not only for the Judge’s views but for his helpful citation of the relevant portions of the patent in suit and inclusion of relevant diagrams. I annex to this judgment, the section of the judgment below dealing with the Scholes patent because it is not, as I think it should be, available on a judicial website.
4. The Judge summarised the background to the invention and the relevant part of the description of the patent in his paragraphs 12-24. No complaint is made of this. It is now accepted that the Judge was right to hold claim 1 invalid. Claim 7 is dependent on claim 1 so it is convenient here to set out the two claims with their features combined. This is the monopoly of claim 7. Mr Purvis for the Appellants helpfully provided us with this, setting it out in numbered paragraphs:
“1. A component for use in a panelled roof unit, for connecting a glazing bar which carries one or more roof panels either to another such bar or to a structural wall to which the roof unit is to be secured;
2. the component having a channel running parallel to the longitudinal axis of the component;
3. which channel is adapted to receive a screw or other fixing means at any point along its length;
4. by which the glazing bar can be secured to the component at any point along the length of the channel;
5. in combination with an elongate glazing seal adapted to be retained in the channel and to seal against the roof panel or panels;
6. wherein the component is so shaped that the glazing bar, when secured to and/or supported by the component, can pivot about the securing point on an axis substantially parallel to the channel so as to adopt any of a range of connecting angles relative to the other bar or structural wall to which it is connected by the component;
7. whilst retaining the seal between the roof panel or panels and the glazing bead. “
5. The Judge set out his views on the experts in paragraphs 29-31. Mr Purvis does not challenge his preference for the evidence of Mr Emsley. At one point (in relation to obviousness) Mr Purvis advanced the argument that Mr Emsley was too inventive – the sort of argument which I castigated as unhelpful at paragraph 12 of my judgment in Technip France’s Patent [2004] RPC 46. It may be noted that the Judge’s preference for Mr Emsley’s evidence was based on his “depth of explanation” – that is to say he gave better reasons for his opinion. As I indicated in Technip what matters is the reasons for an expert’s opinion, not his level of personal ingenuity. So the Judge’s reason for his preference was entirely soundly based.
6. At paragraph 33 the Judge summarised the attributes of the notional skilled addressee of the patent (the same person who is relevant on obviousness). No point was taken as to that.
7. At paragraphs 34-38 he summarised the common general knowledge. This involved resolving a dispute about the common general knowledge of self-drilling (strictly self-drilling, self-tapping) screws. He held they were not only commercially available but were in regular use within the conservatory industry. So such screws would be part of the background knowledge of the reader of the patent.
8. Mr Purvis suggested that it was not common general knowledge for such screws to be used to join two pieces of metal. He showed us some evidence of Dr Kent to the effect that there is a danger of the thread being stripped. Mr Kitchin showed us a catalogue which showed us a number of metal items joined by a self-drilling screw. Self-evidently whether there is a danger or not will depend on the nature of the metals, the screw (including the length of the “drill”) and other factors. What Mr Purvis was unable to show was that a skilled man would reject the use of a self-drilling screw for joining two pieces of metal, even though he might be aware of the potential problem. So it remains the case that the skilled man would reasonably contemplate using such screws as one of the possible fixing means covered by claim 7.
Construction
9. At paragraphs 42-43 the Judge construed a number of elements of the claims. Mr Purvis complains that he failed to construe item 3 of claim 7 – the words adapted to receive a screw or other fixing means at any point along its length. All he did, says Mr Purvis, is in paragraph 42(b) to note that claim 7 added this feature. But the Judge did consider the fixing means, rightly holding that it could be any of a variety of well-known things: nails, screws (of all sorts), nuts, captivated bolts and so on. As I have said a self-drilling screw formed part of the notional skilled man’s armoury for fixing things.
10. Moreover the Judge at paragraph 42(h) considered the word channel noting its purpose in the specific embodiment of claim 6, that it “serves to accommodate both the securing screw and the glazing seal.” And he went on to say in paragraph (i) (which I repeat here):
“Mr Purvis made much of the bonus of not having to drill pilot holes to accommodate a screw (when a screw is used) when using a `channel'. This may be so, but it is not part of the invention- and neither is it claimed by (for example) requiring a deep channel or without the use of a pilot hole.”
11. This to my mind is in effect construing the words – so as to reject Mr Purvis’ contention that “adapted to receive” is limited to the case where the fixing means goes only into the channel and no further.
12. But whether or not the Judge explicitly or implicitly construed the words, I have no hesitation in rejecting Mr Purvis’ construction. At its heart it relied upon a sentence in the description of the specific embodiment which of course involved the use of screws. It is the sentence already quoted by the Judge at paragraph 16 with added emphasis. I repeat it here:
“Since the component will usually be manufactured by an extrusion process, this reduces manufacturing costs as well as providing flexibility in use by providing continuous screw access without the need to drill several separate securing points in the component”
13. Mr Purvis submitted that this was the inventor’s purpose and so “adapted to receive” meant and meant only continuous screw access without the need for pilot holes. But this will not do for two principal reasons. Firstly whether or not a channel is adapted to receive a fixing means must depend not only on the shape of the channel but the, unspecified by the claim, shape of the fixing means. Consider screws of different lengths – one a size which will just fit within the channel and one which is longer and needs a pilot hole (if it is self-tapping) or even a thread (if it is not). The channel is “adapted” for one but not the other.
14. More fundamentally, this is to elevate part of a sentence of a description of a specific embodiment to the heart of an invention. It must not be forgotten here that the real point of the invention is based on the “surprising discovery” that flexibility can be achieved (see judgment paragraph 15). If doing away with the need for pilot holes were the real point of claim 7 the language “adapted to receive” is hardly the appropriate way of limiting the claim.
15. In this context it must also be remembered that the skilled man, without any input from the patentee, would have as part of his mental tool-box, knowledge of methods of doing away with the need for pilot holes, if that is a problem: captivated bolts and self-drilling screws form part of the armoury in addition to simply making a deep-enough channel. So I do not see why, reading claim 7 purposively, he would read it narrowly as suggested by Mr Purvis.
16. Mr Purvis at another point his argument (that relating to Windsurfing step 2) summarised the inventive concept of the claim thus:
“A component for fixing a glazing bar to a structural wall, comprising a longitudinal channel acting as a single receiving means to accommodate both the fixing means and the glazing seal as well as providing a pivot point about which the glazing bar can pivot to adopt a desired angle.”
There is nothing here about the importance of the channel alone containing within it the fixing means. Nor would such an extra limitation help with what is said by the patentee to be the real point of his invention – his “surprising discovery” that you can pivot around the fixing point.
Lack of Novelty
17. The Judge shows the prior art Scope/Sundale device at para. 54 of his judgment. We were provided with a sample (minus its seal) of an actual embodiment. The key part is what looks like a “cup” in the drawing – a cross-section of a groove which contains a seal and into which self-tapping screws are driven to fix the glazing bar. The instruction reads “Fixing through glazing bar No. 8x19.00mm Pan Hd s/s s/tapping fixing screws”. As self-tappers were used a pilot hole would be necessary. The body of the screw goes into the channel and it is driven in until the head engages the top of the cup. Some (10%) of the fixing strength comes from engagement with the lips of the cup, but most from engagement with the self-tapped hole at the bottom of the channel (90%). There is no dispute that the system provides the flexibility said in the patent to be surprising and hence destroys the novelty of the main claim.
18. The only suggested point of difference from claim 7 depends on the construction point – if the claim is narrow and requires the fixing means to be wholly within the channel then Sundale is potentially different if one concludes that screws (of whatever sort) must be driven through the bottom of the channel.
19. However for the reasons I have given I do not construe the claim so narrowly. In my opinion the Scope/Sundale device falls within the claim and so destroys its novelty.
Obviousness
20. Having reached this conclusion (as did the Judge) I am tempted to leave things there. But since the point was argued I will deal with it briefly
21. Often, as I pointed out in Technip France (para. 114) it is difficult for a court to consider obviousness having concluded lack of novelty. A conjecture has to be made. Obviously it can be done in principle – and it is easier in a case involving a single simple conjecture. In Technip the judge had found several points of difference from the prior art and so would have had to make several different conjectures.
22. Here it is possible to make the conjecture – to suppose that the claim required the fixing means to be wholly within the channel. If one does, then it seems to me that the idea must be obvious over Scope. All one has to do is modify the channel so that the screw can screw into it, or use a captivated bolt, for instance. Such methods of holding things together formed part of the common general knowledge. A good illustration of that and a screw fixing appears in one of the standard works, Spencer.
23. Mr Purvis suggest that realising you could use the same channel for the fixing means and the seal would require a spark of imagination. I am baffled to see why. That is what Scope does, and all that is required by way of variation from it is to use another sort of fixing means – one that is very well known.
24. Mr Purvis suggested that the Judge, having properly directed himself in law at para. 59, failed to apply the directions properly. In particular he failed to identify the inventive concept of claim 7 as opposed to that of claim 1. But when Mr Purvis attempted to identify the concept of claim 1 he did so as I have set out in para 15. What is said to be clever is using the same channel for glazing bead and fixing – a dual function. I remain at a loss to understand why the notional uninventive man would miss that – it is just what is done in Scope. Only a really stupid engineer would not use the same channel for both.
25. Mr Purvis also asked the patentee’s perennial forensic question, “why wasn’t it done before?” He submitted that the Scope system must have been known for about 4 years before the priority date of the Scholes system, yet no-one modified it so as to use captivated bolts or self-drilling screws. Yet now, he submitted, the industry had all gone over to using captivated bolts. This point was not pleaded. Nor was it raised before trial until there was an oblique reference to it in a late witness statement. The point was not to my mind raised properly. There are all sorts of reasons why a particular engineering choice is made – they were not explored here for the good reason that the point was not an issue.
26. I think Mr Purvis was miles from showing that the Judge had erred in principle, which is the only basis on which the Court of Appeal can interfere with a finding of obviousness. If anything, only a contrary conclusion would be perverse.
27. In these circumstances it is unnecessary to go further on the question of obviousness (Mr Kitchin argued two other routes). The plain fact is that given Scope, the use of other fixing means would be a self-evident workshop variant.
28. For these reasons I would dismiss this appeal.
Lord Justice Chadwick:
29. I agree.
Lord Justice Kennedy:
30. I also agree.
Annexure: Judgment of HHJ Fysh on the Scholes Patent
Introduction
I have before me two actions by The Burnden Group PLC ('Burnden') for infringement of patent no 2 259 926 ('the Scholes patent'). The Scholes patent ('Roofing Component') relates to components used in the construction of the roofing of conservatories. The defendants in one action are Ultraframe (UK) Ltd (`Ultraframe') and its technical director, Mr Christopher Richardson. Mr Richardson has been joined as an alleged joint tortfeasor. In the other action, the defendants are Northstar Systems Ltd (`Northstar') and Seaquest Systems Ltd ('Seaquest'). In this case, a Mr G J Fielding who is said to be the moving force behind Burnden, is a Part 20 defendant. The claims against both Mr Richardson and Mr Fielding have been stayed pending the determination of the substantive dispute. I have also had another matter to adjudicate, an application by Burnden in the Ultraframe action to revoke another patent of later date but in the same field owned by Ultraframe-as I shall explain below. Mr Iain Purvis represented Burnden. All the defendants (whom I shall collectively call `Ultraframe' unless the context otherwise requires) were represented by Mr Adrian Speck.
Ultraframe have counterclaimed for the revocation of the Scholes patent on the grounds of lack of novelty and/or obviousness in the light of two prior art conservatory systems, each being alleged to contain components falling within all the claims of the Scholes patent. In respect of each, in the grounds of invalidity (1/7 – i.e. volume 1, tab 7 of the court bundles. The same nomination will be used throughout this judgment) reliance is placed on the prior publication of both technical documentary material relating to the systems and to the manufacture and sale of the conservatory roof systems themselves.
Burnden also apply to revoke Ultraframe's patent No 2 332 687 ('the Ultraframe patent') as part of the relief prayed for in the Ultraframe action on the grounds of lack of novelty and/or obviousness in the light of two items of prior art, one made by Northstar (the 'Quickfit' system) and the other by Ultraframe (1/5). For this purpose, no distinction was made between the disclosures in the two citations. This patent dates from after that of the Scholes patent, having a priority date of 1997 - as opposed to that of 1991 for the Scholes patent.
Overview of the Issues
Both infringement and validity have in the end come down to just two claims of the Scholes patent: Claims 1 and 7. In fact, Burnden's expert's report appears to have been directed only to claim 1 in this regard.
As to infringement, the acts said to amount to infringement (which are different in each case) are admitted but infringement is denied. There were originally two non-infringement arguments, called for convenience, the `kit of parts' (or combination) argument and the`glazing bead' argument. The `kit of parts' argument has been adjourned and I need hardly refer to it in this judgment.
The validity of the Scholes patent is undoubtedly the major issue in the case. Two prior art conservatory systems were cited by Ultraframe: The Scope System or `Sundale' conservatory and the `System 10'. The experts agreed that for present purposes, in respect of both the Scope/Sundale and System 10 conservatories, the issues were the same since the relevant components were similar. Furthermore, the System 10 conservatory is admitted to have been made available to the public before the priority date of the Scholes patent.
During 2003, the Scholes patent was acquired by the Burnden Group plc by assignment from the patentee. Mr G J Fielding, the Part 20 defendant in the Northstar/Seaquest action was described as the leading light in the Burnden Group. I mention this because the present patent litigation is part of a cascade of litigation in the High Court which has embroiled these litigants.
Some time (and evidence) was taken over these parallel and emotive maters. There has already been a trial of a preliminary issue (Laddie J) which went to the Court of Appeal. A massive High Court action, so I was told, looms for November 2004 in which allegations of dishonesty, forgery, sham company transactions, intimidation and so forth will be ventilated. Mr Speck told me that the present proceedings were `tactically motivated' – hence he said, the presence of Mr Richardson as third defendant in the first proceedings. – and perhaps of Mr Fielding as Part 20 defendant in the second.
One further preliminary matter may be mentioned. Shortly before trial, Burnden applied to amend the Scholes patent. An outstanding issue was whether the discretion of the court should be exercised in Burnden's favour allowing the amendment. At a directions hearing in the amendment case, I ordered the disclosure of certain documents by Burnden in the light of this issue. However, on the very day that this disclosure was due, Burnden withdrew its application to amend.
For the record, in adjudicating the present cases, I have disregarded all these inter parts issues, despite intermittent suggestion of their relevance by counsel.
Background to the Invention
It will be apparent that these actions are concerned with patents for conservatories and in particular with components for use in the fixing of glazed conservatory roofing. Conservatories are of different kinds and styles but in all of them a glazed roof section has to be joined and fixed at an angle to a load-bearing element - say a vertical section (such as to a door jamb or to an external support wall) or to a wall-plate for a lean-to conservatory. In addition it frequently happens that valleys and ridges have to be catered for. In all these cases a problem had been to secure the integral fixing of the glazing bars to the load-bearing element having regard to the variable contact angle which inevitably arises between them. To illustrate the point, the claimant's expert Dr Robin Kent provided some drawings in his report from which the problem which I have mentioned may readily be appreciated. I have reproduced some of these drawings below. In each case the contact angle between the glazing bar and the eaves beam varies depending upon the construction in question. The angle may I understand, be required to vary between 5 and as much as 40 degrees.
Changes in conservatory wall height also changes the glazing bar to eaves beam contact angle.
It should however be borne in mind that this is not the problem with which the Scholes patent is concerned. It was a problem (termed `flexibility' in the patent) which had already been solved before the priority date and, as I will show, is in fact the entree for the Scholes proposal.
The Scholes Patent
The patent concerns a component for use in constructing panelled roof units which are used for example in conservatory construction. The roof units in such structures are made of glass (or polycarbonate) panels carried in extruded aluminium glazing bars. The component in issue essentially provides a means of fixing glazing bars between vertical structures and the panelled roof units on which they rest at an angle. The component is also suitable for use in the construction of ridges and valleys in conservatories.
First, I should just mention some trade nomenclature. A component which joins a roofing unit to a conservatory wall is known as an `eaves beam' or `ring beam'. It is generally hollow and box-shaped and runs along the top of the wall and requires to be fixed both to the wall and to the glazing bars. A component which joins a roofmg unit to the wall of the house is called a `wall plate'. A component which joins two roofing units together in a valley is a `valley gutter' and one which joins roofing units together at a ridge is a `ridge bar' or `ridge beam'. The Scholes patent contains examples of all these joining components.
The patent has been drawn in classic `problem and solution' fashion. First, the background to the invention is described both in narrative and by reference to Figures 1-5 (I shall have to return to a particular element of prior art conservatory roofs later (the ‘glazing bead’). At the priority date there was, so one is told, a problem with known roof joining components (p2, 11 8-29):
"In the past, components such as wall plates, ridge bars etc for supporting or connecting roof panels and glazing bars have been custom - made to accommodate the glazing bar at a particular angle. More recently, universal components have been designed which comprise at least two parts hinged or pivoted...together.... "
"However, whilst such components offer the desired flexibility they are necessarily more complex to produce because each comprises at least two separate pieces which must be manufactured separately. Ideally, a component for use in connecting a glazing bar, would provide flexibility in terms of connecting angle whilst also being of relatively simple design and inexpensive to manufacture."
The solution which is then proposed (in the consistory clause) is in the form of the claimed component. It is predicated on what is said to be the `surprising discovery' (p3 11 11-24):
"...that it is still possible to achieve flexibility in terms of the connecting angle...without the need for hinges or pivots, simply by using the point of fixing the bar to the component or the point at which the bar is supported by the component, as a pivot point for the bar. Provided the component is suitably shaped, both to hold the bar in position and also to accommodate its pivotal movement about the securing point, a range of different connecting angles can be achieved using a single piece connecting component." [Emphasis added]
Having been drafted in such uncompromising `problem and solution' terms, one must I consider, read the patent in the light of the solution spoken of and not in terms of adventitious benefits which may flow from the use of the construction proposed.
The claimed component may of course be used in the usual manner viz. with a wall plate, eaves beams or with valley or ridge beams. It is typically a single piece of aluminium extrusion. The component is fashioned with alternative `receiving means' as follows, the second being the preferred alternative (p411 17-33):
"The receiving means of the component may comprise a screw port, adapted to receive a conventional threaded screw used to secure the glazing bar to the component at the securing point. However, the receiving means preferably comprises a channel running parallel to the longitudinal axis of the component, which channel is adapted to receive a screw or other fixing means at any point along its length. This offers great flexibility in terms of the position at which a glazing bar can be secured to the connecting component. Since the component will usually be manufactured by an extrusion process, this reduces manufacturing costs as well as providing flexibility in use by providing continuous screw access without the need to drill several separate securing points in the component." [Emphasis added]
A glazing seal is provided which is also to be inserted into the `receiving means' so as to seal the joint between the component and a roof panel. The patent says:
"The receiving means is preferably also capable of receiving a glazing seal used to seal the join between the component and a roof panel...carried by the glazing bar."
As will be seen, in claim 1, this latter preference is in fact an essential integer of the invention.
The benefit of the Scholes proposal is re-stated thus (p 5,11 12-16):
"This [proposal] ultimately makes the component easier to manufacture and to use, and represents a considerable improvement over previously known connecting components where separate means must be provided, on the components, for receiving glazing seals where needed"
A preferred embodiment of the invention is described (called at trial the `open jaws' embodiment) wherein the component has the general shape of a set of open jaws between which one end of a glazing bar can be accommodated (p511.21-34 and p 6 11. 1 and 2). One of the jaws:
"....having the receiving means and the other having bead support means for supporting the glazing bead, the overall shape of the component being such that a glazing bead supported in the bead support means abuts the roof panel... carried by the bar and such that the end of the bar can be accommodated between the jaws of the component over the entire range of angles which the bar can adopt when secured to and /or supported by the component.
This particular embodiment of the invention allows the glazing bar essentially to pivot about two points one being the securing of the bar to the component and the other being the point of contact between a bead supported in the component and a roof panel carried by the bar."
The open jaw arrangement has an additional benefit as regards the glazing bead which I have already mentioned in connection with the prior art. For reasons which will become apparent, I should focus briefly on this glazing bead. In the background section of the patent, it is described thus (p 1, 11 24-29):
" Elongate glazing beads also carried by the glazing bars, are used around the periphery of the roof panels to seal the gaps between the top of each bar and the panel or panels in it and to provide a `finished' appearance to the roof as a whole."
In the context of the claimed component, the traditional role of the glazing bead is accommodated in the `open jaw' configuration.
"Whilst the end of the bar can always be accommodated between the jaws of the component, it is also true that, whatever angle the bar adopts, a glazing bead supported in the component contacts the roof panels(s) carried by the bar providing a good seal and an acceptable `finished' appearance and closing up the gap which would otherwise be present between the component and the roof panel(s)." (P 6 11. 2-9)
The glazing bead thus performs its conventional function. Moreover (p 6 11. 15-24)
"The component may include a further glazing bead either as an integral part of the component or supported in the bead support means as a separate but attached item.
"The invention thus additionally provides a component as described above as being in accordance with the invention in combination with a glazing bead capable of being supported in the bead support means of the component."
Provision is also made for fitting `end caps' using `screw ports'. Eighteen figures accompany the specification, the first five of which illustrate conventional practice. I have reproduced some of these figures to illustrate what follows.
In order to demonstrate the benefit of the proposal over the prior art, the patentee refers to Fig 1 which shows in section a typical roof glazing bar 1 carrying two roof panels 2 and 3. The bar is shaped to include two bead grooves 4 and 5 which receive glazing beads 6 and 7 which (p8,11. 11-14):
"..abut the panels 2 and 3 thus providing a seal between the panels and the glazing bar 1, and further providing an aesthetically pleasing finish to the roof unit as a whole."
Screw ports 9 which run the length of the extrusion are used to enable end caps to be attached. The narrative then describes (and illustrates) a number of conventional connecting components in situ such as wall plates, a valley gutter and a ring or eaves beam for use on the top of the wall of a building. All of them show hinges and pivots which in setting up the structure, allow a range of angles to be adopted between the outside wall, structural wall etc and the glazing bar. Each of these conventional components:
"....is made up of several pieces which must be manufactured separately and hinged together during assembly. This fact and the need to produce constituent parts with hinge elements on them, makes these conventional connecting components relatively complex and costly to produce."
The invention is first described by reference to what I have already referred to as the
`open jaws' embodiment of the invention, the jaws defining a space into which the glazing bar is accommodated.
"In this case, the component is usually a wall plate, ridge bar or valley gutter."
In the drawing below (Fig 6 – see also fig 8 which shows an entire lean-to conservatory in erected position), a wall plate 1 is fixed for example to the outside wall of a building against which a lean-to conservatory with a panelled roof is to be built. In the drawing , it will be seen that the aluminium extrusion is in the form of upper and lower jaws, 25 and 26 respectively.
" Upper jaw 25 is shaped to include a bead groove 16 in which an appropriately shaped glazing bead 17 is located. This bead may be provided as part of the wall plate 14 or may be fitted separately by the user."
The lower jaw 26 has a channel 15 which can accommodate a conventional self-tapping screw such as 22 at any point along its length together with a glazing seal 28. The position of the glazing bar 18 (together with the roof panels which it is carrying) is shown schematically in three positions in Fig 6 (19, 20 and 21) where it is secured in position between the two jaws at the desired angle by means of the self-tapping screw 22. Thus, by being able to pivot, the bar can adopt a range of connecting angles relative to the structural wall of between 60° and 871n °.
"This flexibility arises even though wall plate 14 is constructed from a single piece of relatively simple design."
The wall plate can also be designed to accommodate an even greater number of connecting angles if desired. Parts of the glazing bar (such as shaded area 24) may need to be cut away during pre-installation - it having been common ground that these structures were almost always pre-erected before being installed. Screw ports (see above) are provided for locating the end caps. It may even be possible to omit the securing screw altogether if the bar is otherwise `held reasonably firmly in position': seep. 1311.30-38 and this may result in some benefit in accommodating longitudinal thermal expansion in hot weather.
Page 12, lines 10-12 of the patent reads as follows:
`Channel 15 conveniently serves to accommodate both securing screw 22 and, to either side of it, a glazing seal such as 28.'
Further narrative and drawings are directed to ring/eaves beams, ridge bars and valley bars `in accordance with the invention' (p 7,11. 16-34). I should mention Fig 9 which shows a glazing bar (51) located on an eaves beam (48) which itself is to be placed on a structural wall. Fig 9 has been reproduced below. It can be seen that in this arrangement, there are
no jaws.
The Claims
During the hearing, claim 1 was broken down as follows [X8]:
A component for use in a panelled roof unit for connecting a glazing bar which carries one or more roof panels either to another such bar or to a structural wall to which the roof unit is to be secured
having elongate receiving means for receiving fixing means by which the glazing bar can be secured to the component at any one of a plurality of securing points along the length of the securing means
in combination with an elongate glazing seal adapted to be retained in the elongate receiving means and to seal against the roof panel or panels
wherein the component is so shaped that the glazing bar when secured to and/or supported by the component
can pivot about the securing point on an axis substantially parallel to the elongate receiving means
so as to adopt any of a range of connecting angles relative to the other bar or structural wall to which it is connected by the component
whilst retaining the seal between the roof panel or panels and the glazing bead.
The claim therefore relates to a combination of a component together with a glazing seal.
Claim 7 depends on any preceding claim wherein
The elongate receiving means of the component comprises a channel running parallel to the longitudinal axis of the component
which channel is adapted to receive a screw or other fixing means at any point along its length.
For reasons which will become apparent, I should I think set out claim 11 (which is also dependent upon any preceding claim). It is to a combination
in which the component has the general shape of a set of open jaws between which one end of the glazing bar can be accommodated
one of the jaws having the receiving means
and the other having bead support means for supporting a further glazing bead
the overall shape of the component being such that a glazing bead supported in the bead support means abuts the roof panel or panels carried by the glazing bar
and also being such that the end of the bar can be accommodated between the jaws of the component
over the entire range of connecting angles which the bar can adopt when secured to and/or supported by the component.
I have emboldened certain phrases in the claims in view of what is to come.
The Experts
Burnden: Dr Robin Kent
Dr Kent's academic background is in materials engineering culminating in 1979 with a Ph.D. in Solid State Physics from the University of Guildford. His professional career began with REHAU Plastics Ltd (`REHAU') where he was UK technical manager having responsibility for `new product families' including products for the window industry. In fact he had specific responsibility for management and development of the REHAU windows and conservatories department in Slough. From 1989 to 1991 he was employed as group technical director within the Thurgar Bardex plc group, being technical director of a number of companies. There he had responsibility for designing windows in PVC-U and for the manufacture and supply of conservatories. In 1991 Thurgar Bardex plc was taken over by Heywood Williams plc and from then to 1996 he became technical director of companies working in the design and manufacture of window, conservatory and door
products which included the design of products in both steel and aluminium. He has held positions in a number of national committees in the field of windows and from 1991 to 1993 was chairman of a national working group which produced the first edition of A Guide to the Survey and Installation of Conservatories (1993). In 1996 he set up Tangram Technology Ltd, consulting engineers, of which he is presently managing director. He still sits on a number of technical committees including an organisation called The British Fenestration Rating Council.
Ultraframe: Mr Roger Emsley
Mr Emsley now considers himself to be `semi-retired'. He became a design consultant in 1966. Between 1973 and 1977 he was chief engineer and technical sales manager at Catnic Components Ltd whose line of business must I should think, be well enough known to most practitioners in the patent field. He then became technical director at Monarch Aluminium Ltd where he was responsible for inter alia new entrance and patio door products. In 1982 he founded Designex Engineering Consultancy which offers design consultancy in extruded products to companies in the building industry. During this time he provided specialist services for a number of well-known companies in the conservatory and double glazing fields and has designed some 14 different conservatory systems (or `kits'). Within the industries with which he has been associated, Mr Emsley has been involved in most stages of the business, from initial drawing and design right through to the assembly of commercial prototypes. He has also written assembly manuals and brochures for point of sale applications. On being asked by Mr Purvis about his experience in the conservatory field, he agreed that he was probably one of the most experienced conservatory designers in the country: D3/435.
Both gentlemen were good experts. Their evidence was fair and clear and I felt that they were doing their best to assist the Court. Mr Emsley's depth of explanation struck me as being fuller and better informed by experience than Dr Kent's and in cases of difference between the two I have tended to prefer Mr Emsley's evidence.
The Addressee and the Common General Knowledge
I was not addressed on the law relating to either of these topics and do not believe there to have been any significant difference in approach between the parties in this regard. As is usually the case in patent actions, both experts were far more `skilled' than the notional skilled addressee would be. For the record, I have taken the relevant considerations to be those set out in Terrell 15edn §§ 6.25-6.28.
The Skilled Addressee in this case
In the end there did not appear to be much between the parties on this subject. The notional skilled addressee is in my judgment a person with a mechanical or structural engineering background (with a degree or qualification to HNC standard)who had practical experience in designing conservatory systems and products for use in building conservatories and in the assembly of such systems. A `team' was not proposed by either party, though (see below) the addressee would be expected to consult with aluminium extruders if a new extrusion was required for some reason.
The Common General Knowledge in this case
The relevant date is September 1991. Again, there seemed little disagreement between the experts on this topic. At that time the skilled addressee would be expected to know about standard types of conservatory roofs on the market, about their cost, performance and weight, about their erection and the practical problems associated therewith. He would know about both his employer's products and those of the major `competition' (D1/150). In particular the skilled addressee would have been aware of some details of the contemporaneous Ultraframe product which was described as being the best seller by the priority date: Emsley, Report §41 and Kent D2/150. The addressee would also know about the relevant building regulations and safety considerations.
He would also know about the standard accessories, components and materials used in conservatory construction and to be thoroughly familiar with the everyday exigencies of component fixing and conservatory erection. More particularly, he would be familiar with the various nuts and bolts, rivets, brackets, the types of screws and screw ports and suchlike which were then regularly in use in connection with aluminium extrusions for structural purposes. Self-tapping screws (i.e. screws which make their own thread) and self-drilling screws (i.e. screws which make their own hole and thread and thus require no pre-drilling) require to be considered separately however, as this was one of the few areas of disagreement between the experts on this aspect of the case.
The skilled addressee would be expected to know about the materials used to construct conservatories and in general terms something about extrusions in aluminium and plastics and the mechanical properties (and limitations) of such extruded products. He would not be assumed to know about the detailed extrusion design or about extrusion manufacture, this knowledge being available `out-house' as required. He could nevertheless liase with and seek the advice of dedicated extruders if required (D2/166 ‘a two way process’).
There were it seems two `Bibles' in use at the time which would have been in the possession of (or at any rate be within ready reach of) the skilled addressee. The first was a book called Aluminium Extrusions: A technical Design Guide by Spencer (B/7): see Emsley's Report §30 and Kent D2/170 Can excellent book') and 192-194.This was referred to in the evidence simply as `Spencer'. The second was a work called Conservatory Designs and Installations by Branson & Beckendale Associates (Vol 8C/18) which was published a little before the priority date. This was much referred to by Dr Kent in his report. He considered it to be ` a pretty good summary of the knowledge just before the priority date of the Scholes patent' (D1/134), though somewhat light on technical detail.
Stainless steel self-drilling screws and self-tapping screws
The relevance of this topic will become evident when I consider obviousness – even though the Scholes patent refers simply to a `screw'. Mr Emsley was of the view that these items and thus their practical utility were within the general knowledge of the skilled addressee at the priority date' (report §38 and D3/484-486); Dr Kent was of the opposite view. I need in fact hardly dwell upon self-tapping screws as there was ample evidence of their widespread availability and use well before the priority date: see for example Spencer p 81 where they are described asbeing a standard method of joining inter alia aluminium extrusions in doors etc at the time. They require a pre-drilled pilot hole to be made having a diameter slightly less than that of the self-tapping screw which is to be put into it. Regarding self-tapping screws, I doubt if there was much between the experts in the end. Self drilling screws remained however an area of difference. On this topic, Mr Emsley's evidence is I think, to be preferred for the following reasons:
Self-drilling screws are certainly described as being `available' in Branson & Beckindale at pp.2735-2736. See also X4 and Dr Kent's cross-examination thereon: D2 /174-177
They were being used in the Scope Sundale System (i.e. one of the cited items of prior art) before the priority date: see Exhibit Cl and the evidence of Mr John Hutchins who tendered this exhibit (See Hutchins’ second witness statement). Mr Hutchins, (whom I found to be a satisfactory witness), was the managing director of a fabricator and installer of conservatories in the north of England. His business had installed Scope Conservatories from 1979 until 1995. His evidence was that his firm regularly used both self-tapping and self- drilling screws in connection with the erection of Scope conservatories. Whether or not used without drilling a hole before insertion is not relevant to their evidently ready availability.
The corroborative evidence of an Austrian witness, Mr Robert Hoellrigl of WHS Halo Ltd. His company supplied the System 10 conservatory (also cited as prior art) in the period 1989-1993.His firm was using self-drilling screws from the 1980's: See Mr Hoellrigl's witness statement, X5 and Dr Kent's cross-examination at 2/184-186.I found Mr Hoellrigl to be a satisfactory witness.
The evidence relating to what Dr Kent's former employers REHAU were doing in 1991: see X6 and Dr Kent's cross-examination at 2/187-190
The evidence of a Mr C.M White who from 1973-1996 worked with BKL Extrusions Ltd, ultimately becoming their marketing and design director. BKL's trading name for the conservatories they manufactured during this time was `Scope Systems', i.e. the entity already referred to. One of these conservatories sold to fabricators by the Scope Division of BKL was marketed under the name `Sundale Conservatories', that is, it was one of the cited items of prior art. Mr White gave evidence in two witness statements and was cross-examined on several topics relating to the Scope/Sundale product (see below). I found him to be a fair witness who had a good memory of events dating from before and at the time of the Scholes patent (see D3/393, 1120-23, for example). His firm first started using self-drilling screws in 1984. By the priority date (late 1991), there were it seems two varieties of such screws, the `yellow passivated' (which was not rust -resistant and therefore unattractive for use in conservatories) and stainless steel (which was) His recollection is that the latter came into use `for our industry' in the `early 1990's’ (D3/387-388,417).
In the light of this evidence, I am of the view that a number of self-tapping and self-drilling screws (including those made of stainless steel) were not only commercially available to the building trade by the end of 1991 (I do not in fact think that this is now in dispute) but were actually being used on a regular basis by designers, fabricators and erectors within the conservatory (and related industries) to fix aluminium components and that such persons well understood their applications and utility.
Construction
The principles applicable to the proper construction of patents were also not in dispute. In brief, I have approached the construction of the Patent in accordance with s. 125 of the Patents Act 1977 ('the Act') and in the light of the Protocol on the Interpretation of Article 69 EPC. A patent is of course a working document aimed primarily at those having a practical interest in the field in question. The need for purposive and contextual construction through the eyes of the skilled addressee blessed with the common general knowledge of the art was stressed by both counsel: Catnic Components Ltd v Hill & Smith Ltd [1982] RPC 183. Mr Speck also referred me to Glaverbel v British Coal [1995] RPC 255 at 281 for the proposition that subsidiary claims may be used to give guidance on the construction of antecedent claims. The need to avoid either a literal interpretation of the claims or a construction which was plainly not intended by the patentee was also stressed. Both counsel reminded me of the need for a reasonable degree of certainty in the minds of skilled third parties reading a patent.
There were no words in the specification for which the court required the experts' assistance to understand their meaning within the field in question. In other words, all the words and phrases considered below bear a normal English meaning — in context.
Applying the foregoing, Mr Speck first reminded me that the Scholes patent is a classic `problem and solution' patent. Giving any part of it a purposive construction must be carried out with the solution suggested in mind: see §15 above. Basically the patent offers the conservatory designer the desirable degree of flexibility to the angle of pitch of the roof (which was in fact already available) but without the need for using such things as hinges or pivots to do so. He also stressed that the `flexibility' referred to in the patent was related to the angle of pitch of the roof (i.e. the glazing bar) and not the ability to move the glazing bar at right angles viz. along the length of the component during erection. I believe Mr Speck to be right in this respect.
Specific issues on construction arising in the claims
`Elongate receiving means for receiving fixing means'
First, `receiving means' and `fixing means' as used in claim 1 are words of a most general kind. Mr Speck went further. He insisted (correctly in my view) that any kind of receiving means together with any kind of fixing means would also provide the flexibility with which the patent is concerned and would make use of the `surprising discovery' which is said to underpin the invention viz. using the same point to fix and pivot.
In addition to receiving the fixing means, the receiving means is also adapted to retain within it the elongate glazing seal, the second item of the claimed combination. When one reaches claim 7, the `elongate receiving means' becomes a restricted to being a channel running parallel to the longitudinal axis of the component which is adapted to receive a screw or other fixing means.
As for, `fixing means'; there is nothing in the body of the Scholes patent (or in its claims) that makes the reader aware that any significance is being attached to the actual means of fixing - other than by the `screw or other fixing means' of claim 7. But note that in terms of the `surprising discovery', the means must be a `single piece connecting element' : see §15 above. The evidence shows that this could cover anything from nails through a variety of screws to rivets, nuts and captivated bolts. The patentee is evidently not much concerned with the means available to the constructor to achieve a necessary (and of course satisfactory) connection; he will make use of what is suitable and available.
Next, I turn to the `receiving means' and the `channel'. It is as well to remember that the reader of the Scholes patent is here concerned with a solid physical entity, an extruded component in fact, and not with some abstract form or mathematical envelope. Both these objects comprise opposed top lips, two sides and a base. In my view, any of these are parts of the receiving means or indeed, of the channel.
Receiving means denotes an elongate space running the length of the extrusion which is suitable for putting both the fixing means and the glazing seal into. It need not have any particular cross-sectional profile but when fixing means is put into the receiving means, both items must contribute to providing a satisfactory conservatory cover and fulfil the purpose of the invention. `Channel' is of course a `receiving means' but with a modest qualification. A `channel' to some degree assists or directs the accommodation of the fixing means (and the glazing seal); it imports a notion of direction to the fixing means.
The narrative provides some guidance as to what Scholes actually had in mind with regard to these terms. He gives two examples: a screw port and a channel (see § 16 above). Both are obviously `receiving means'.
The screw port alternative deserves rather more attention than was given to it at trial; in fact, Dr Kent did not I think, even consider the `screw port' receiving means in his report at all. I have already drawn attention to the `screw port' in relation to items 9 shown in the prior art Figure 1 of the Scholes patent: see § 21 above and have no reason to think the usage is any different when the item is referred to in relation to the invention. It will be recalled that the screw ports of the prior art were present to secure end plates. But that is not their only use. Mr Emsley gave evidence (Report 7A/32(a) which was not cross-examined to, showing that screw ports can be used to receive fixing screws at 90° or thereabouts. He also set out (and illustrated) his understanding of how the screw port described on p. 4 of the Scholes patent might be made to work in practice: Report § 63-65. He also said that this could be done while still exploiting the `surprising discovery' upon which the invention is predicated. There was cross-examination of both experts on this point and I have reviewed this evidence on it. I am of the view that Mr Emsley's evidence on the point was not significantly shaken and I accept it. The screw port may or may not be a channel as I understand the term.
A channel is the preferred exemplification of the receiving means and features in all the examples given in the patent. I have already set out relevant passages and drawings which show this `channel'. The reader is given some further assistance as follows: unlike the screw port, a channel gives a reduction in manufacturing costs
`as well as providing flexibility in use, by providing continuous screw access without the need to drill several separate securing points in the component.'
Also (p 12,11 10-12), a channel `serves to accommodate' both the securing screw (22) of fig 6 and the glazing seal (28) to either side of it
Mr Purvis made much of the bonus of not having to drill pilot holes to accommodate a screw (when a screw is used) when using a `channel'. This may be so, but it is not part of the invention- and neither is it claimed by (for example) requiring a deep channel or without the use of a pilot hole.
`While retaining the seal between the roof panel or panels and the glazing bead'
Claim 1 requires that the component is so shaped that the glazing bar can pivot about the securing point and in such a way that when it does so, the seal between the roof panels and the glazing bead is retained. Mr Speck submitted that claim 1 was thus limited to a component that is shaped to enable a glazing bead to be used in conjunction with it i.e. so that the seal is retained between the roof panel and the glazing bead as the glazing bars pivot. This he said covered all the `open jaws' type of components (see Fig 6) but excluded the eaves beam (see Fig 9).
In support of this submission, Mr Speck pointed to the fact that this integer had been introduced into claim 1 during prosecution. If such a construction had the effect of leaving a number of examples of the invention as originally proposed, `stranded' (c.f per Laddie J in Russell Finex v Telsonic 17 March 2004, unrep. at §39) ,that was not unusual and had been forced upon Scholes (for whatever reason) by the examiner.
I reject Mr Speck's submission for a number of reasons. First, it would I think be immediately apparent to the skilled reader that the `open jaws' embodiment cannot be used for eaves beams otherwise the glazing bead in question would obstruct the passage of rainwater into the gutter, But having regard to the definition of `glazing bead' given in the patent (see § 19 above (and even more clearly by Mr Emsley in his report 7A/§26(c)) there are other positions at which gazing beads can be placed – for example at the side edges of the roof panels.
Mr Emsley provides the following definition of `glazing bar' in his Report: §26 (c)
"A `glazing bead' is a thin rigid component (conventionally incorporating a gasket or seal) which provides the finished weather seal around the top and side edges of the roof panels. No glazing bead is used on the bottom edge at the eaves, because it would obstruct the drainage of rainwater into the gutter." [Emphasis supplied]
There was no cross-examination concerning this definition.
In addition, claim 3 is directed to an eaves beam and the embodiment with a glazing bead in the upper jaw is specifically introduced in claim 11 - where it is referred to as a `further glazing bead'.
[in paragraphs 44-51 the Judge dealt with infringement]
Validity
General
Only claims 1 and 7 need be considered for this purpose. As noted, two items of prior art have been relied upon to support pleas of both lack of novelty and obviousness. The prior art extrusions which are very similar in design, are illustrated in copy documents annexed to the pleadings, the Scope/Sundale Conservatory extrusion being described at Annex A and the System 10 extrusion being described Annex C respectively: see 1/7 (in his skeleton argument, Mr Speck annexed these drawings as Tab 2 and 3 respectively). Relevant drawings are to be found in Vol. 3 pp 248 and 266 (Scope/Sundale) and 416 (System 10).
In my judgment, both prior art proposals make use of the `surprising discovery' upon which Scholes is based viz. to give flexibility to the angle of the glazing bar during pre-assembly or erection whilst using a `single piece connecting component'. The relevant difference between the proposal in the Scholes patent and the prior art device is that in the latter, the fixing means (in practice a self-tapping screw) penetrates through the bottom of an elongate cavity made for fixing the eaves beam whereas in the `channel' illustrated in Scholes patent it does not do so, being engagingly gripped by the walls of the channel alone. Mr Speck submitted that the difference had nothing to do with the invention described and claimed in the Scholes patent.
I need reproduce only one of these drawings for present purposes, that depicting the Scope/Sundale extrusion.
The longitudinal cavity which Mr Speck identified as being both the `receiving means' and the `channel' may be seen in the centre of the drawing just under the Bubble Gasket. At the pre-assembly stage the fitter drilled pilot holes into the base of this cavity so as in due course to guide the self-tapping screws. At the moment of fixing, the screw bit into both the material of the lips and into the wall of the drill holes in the base of the extrusion. It was common ground that the prior art systems offered the advantage of `flexibility' which I have already mentioned.
Lack of Novelty: the Law
I was not specifically addressed on this topic. For the record however, the principles which I have followed are those laid down by Sachs LJ in General Tire v Firestone Tyre [1975] RPC 457 at 485 and set out in Terrell 15th Ed, §§ 7.14-7.16.
Lack of Novelty: the Facts
The novelty attack turns upon whether the glazing seal cavity in the Scope/Sundale (or System 10) conservatories is " elongate receiving means for receiving fixing means by which the glazing bar can be secured to the component at any one of a plurality of securing points along the length of the securing means." The outcome of this part of the case therefore largely turns upon my antecedent findings on the proper construction of this phrase in claim 1.The issue has also of course to be considered in relation to the use of `channel' in claim 7.
Mr Purvis argued that the pre-drilled pilot holes were the `receiving means' in the prior art and not the cavity itself. He referred to the evidence of Mr Kent in support of this (report § 109 and D2/239 and 242-243). I reject this argument. In the light of my findings as to the proper construction of the words `receiving means' and `channel' all the requirements of claims 1 and 7 are met in the Scope/Sundale System component. These claims are therefore invalid for lack of novelty.
Obviousness
The burden is of course on the defendants to make good this objection. Again I did not detect dispute between the parties as to the principles to be applied. The approach to obviousness which I shall adopt is the fourfold, structured approach proposed by Oliver LJ in Windsurfing International v Tabur Marine Ltd [1985] RPC 59 at 73:
" ...The first [step] is to identify the inventive concept embodied in the patent in suit. Thereafter, the court has to assume the mantle of the normally skilled but unimaginative addressee... at the priority date and to impute to him what was, at that date, common general knowledge of the art in question. The third step is to identify what if any, differences exist between the matter cited as being `known or used' and the alleged invention. Finally, the court has to ask itself whether, viewed without any knowledge of the alleged invention, those differences constitute steps which would have been obvious to the skilled man or whether they require any degree of invention."
When the issue is one of obviousness, I have of course also borne in mind the numerous warnings from judges against the dangers of ex post facto analysis and the temptations of hindsight. I was also reminded of the fact (which has been stressed by the Court of Appeal in recent times), that in adjudicating obviousness, it is the evidence of the properly qualified expert witness which matters.
I have already considered the inventive concept (in the light of the `surprising discovery'), the skilled addressee and the common general knowledge.
Next, I must identify what differences exist between the relevant prior art components and the alleged invention. This boils down to whether the groove or cavity in the former is the `receiving means' or the channel in the claims. As regards claim 1, since `receiving means' includes a screw port (see discussion above), there is in my view no relevant distinction in this respect. The circular cross-sectional profile of the screw port is of course not identical to the relevant profiles in the prior art systems, but this is of no technical consequence. In my judgment, there is no obviousness issue regarding this claim. Claim 1 is anticipated.
A regards the `channel' of claim 7 however, there may be more to be said and in view of the possibility of my being wrong with regard to my previous finding on this claim, I shall turn to Mr Purvis' attack on this claim based on obviousness. Fig 6 of the drawings in the Scholes patent shows an elongate channel which `engagingly' encloses the entire shank of the fixing screw. Pre-drilling is not required (as Mr Purvis frequently reminded me) and such a fixture he said would be more robust. Let me assume that Mr Purvis is right in this regard.
A conservatory roof must obviously be properly fixed to its retaining means. A conservatory roof which becomes detached during a winter storm would I daresay, be the nadir of inconvenience. At the priority date, there were various ways by which good fixing could be achieved whilst still providing `flexibility' to the erector (which is the entree for the Scholes patent). Furthermore, I have already noted that Scholes is hardly concerned with the detail of fixing – provided of course that it fulfils the purpose of the patent; none is specifically claimed though `screws' are mentioned in the narrative. Thus any appropriate fixing means which would have been available to an erector would be within the ambit of the claims.
What then was available at the time? In addition to self-tapping screws, evidence was given of the use of captivated bolts for this purpose. This would have required the provision of a cavity of different cross-section in the fitting and it was not suggested that the provision of such a modified fitting would involve any inventive quality whatever: Emsley 3/428-429.
I have already held that self-drilling screws formed part of the common general knowledge of the skilled man. They would be another available candidate as 'fixing means', even if they had never been used for this particular purpose before (see Kent D2/190-191,266 and 269 and Emsley 3/484-487). Suppose the addressee chose to use such self-drilling screws for fixing in a prior art component which provided `flexibility'. What would he do? It seems to me that either alone or in consultation with an extrusion manufacturer (see above) he would design a cavity which best exploited the `self-drilling' quality of such screws. As I understand the narrow difference between `receiving means' and `channel', such cavity would almost inevitably be a `channel'.
In my judgment, no inventive step is involved in the process described in the paragraph preceding. Moreover, I cannot see why the provision of a cavity suitable for accommodating a captivated bolt is admittedly non-inventive whereas that for providing a cavity for a self-drilling screw should be. The cross-examination of Dr Kent on this topic 4 was revealing and supports the conclusion to which I have come. The addressee would understand that the `receiving means' might require different profiles to suit different `fixing means'.
Conclusion
For the above reasons, I have reached the view that the Scholes patent is invalid. The claim fails and the counter-claim succeeds.