England and Wales Court of Appeal (Civil Division) Decisions

IN THE SUPREME COURT OF JUDICATURE CHPCF 95/1256/B

COURT OF APPEAL (CIVIL DIVISION) CH 1993-B-No.7779

ON APPEAL FROM THE HIGH COURT OF JUSTICE CH 1993-V-No.6891

Royal Courts of Justice

Wednesday, 12th February 1997

Before:

LORD JUSTICE HIRST

LORD JUSTICE ALDOUS

LORD JUSTICE SCHIEMANN

- - - - - - -

(1) BELOIT TECHNOLOGIES INC.

(2) BELOIT WALMSLEY LIMITED

Appellants/Plaintiffs

-v-

(1) VALMET PAPER MACHINERY INC.

(2) VALMET PAPER MACHINERY (UK) LIMITED

Respondents/Defendants

(Transcript of the Handed-Down Judgment of Smith Bernal Reporting

Limited, 180 Fleet Street, London, EC4A 2HD. Telephone No: 0171-831 3183. Fax No: 0171-404 1424. Official Shorthand

Writers to the Court.)

- - - - - - -

MR. S. THORLEY Q.C. and MR. C. BIRSS (instructed by Messrs Bird & Bird) appeared on behalf of the Appellants/Plaintiffs.

MR. D. KITCHIN Q.C. and MR. R. MEADE (instructed by Messrs

Bristows Cooke & Carpmael) appeared on behalf of the Respondents/Defendants.

- - - - - - - -

J U D G M E N T

(As approved by the Court )

Crown Copyright

The parties in these proceedings are Beloit Technologies Inc and Beloit Walmsley Ltd (the appellants) and Valmet Paper Machinery Inc and Valmet Paper Machinery (UK) Ltd (the respondents). There is no need to differentiate between those groups and I will therefore refer to them respectively as Beloit and Valmet.

Beloit are the registered proprietors of two patents relating to apparatus for drying a paper web. The first, European Patent (UK) 0334 899 which I will refer to as 899 was applied for on l2 November l987 and claimed priority from a Japanese patent application filed on 2 December l986. The second European Patent (UK) 0345 266, which I will refer to as 266, was applied for on l8 December l987 and claimed priority from a US application of l3 February l987.

In October l993 Beloit alleged that the dryer of certain machinery which had been offered by Valmet to SCA Aylesford Ltd infringed 899. Valmet were concerned that the existence of that patent would affect their commercial operations and therefore petitioned for its revocation. That was met by an action for infringement in which Beloit alleged that the dryer to be supplied by Valmet, known as the Aylesford Mk I, infringed 899. Valmet denied infringement and counter-claimed for revocation of the patent. In June l994 Beloit amended their pleadings to add an allegation of infringement of 266. By a consequential amendment of their pleading in August l994, Valmet denied infringement of that patent, introduced a counterclaim for revocation of 266 and added a claim for a declaration of non-infringement in respect of a revised version of dryer known as the Aylesford Mk II.

The combined proceedings came to trial before Jacob J in March l995. In his judgment of 28 April l995 he held both patents invalid. He also held that the Aylesford Mk II would not have infringed even if the patents had been valid, but the Mk I would have. He ordered that the patents should be revoked, but stayed that order pending appeal. Against that judgment Beloit appealed and Valmet served a Respondents' Notice.

To arrive at his decision the Judge had to deal with a considerable number of issues. Our task has been simplified by the clarity of his judgment and by the practical approach of the parties who have accepted many of the findings of the Judge, in particular the acceptance by Beloit that many of the claims of the patents are invalid. Thus the only issues remaining for decision on this appeal are:

A. Patent 899

(1) Is claim 2 novel over US Patent 4359 827 (Thomas)?

(2) Is claim 2 obvious?

B. Patent 266

(1) Is claim 12 obvious?

(2) Does the Aylesford Mk I fall within claim l2?

(3) If the Aylesford Mk I falls within claim l2, is it anticipated by the application for 899?

C. The Relief

Beloit sought to amend their Notice of Appeal so as to challenge the court's jurisdiction to order revocation of the patents during the period when they are under opposition in the European Patent Office.

Valmet opposed both patents and in October l994 the Opposition Division of the European Patent Office concluded that 899 was invalid and ordered its revocation. The subsequent appeal by Beloit suspended the EPO's decision. In October l995 the EPO upheld 266 upon certain amended claims. That decision has been appealed by Beloit and Valmet. Thus there are before the EPO appeals relating to the validity of both patents which will not be determined until the end of this year. In those circumstances Beloit submitted that having regard to section 77(2) of the Patents Act l977 the English courts have no jurisdiction to revoke the patents until after the appeals have been heard. The appropriate relief, upon the Judge's conclusion, was declarations confined to the issues decided by the court.

Valmet resisted the amendment to the Notice of Appeal and challenged the submission of Beloit. Thus this Court has to decide:

1. Should Beloit be given leave to amend their Notice of Appeal?

2. If so, was the Judge right to order revocation of the patents?

Beloit and Valmet are substantial concerns engaged in designing and making papermaking machines. Such machines are very large and can for example be 40 ft wide, 60 ft high and 200 yds long. They cost in the order of £40m each.

The usual starting material to make paper is wood pulp which is refined, blended, treated and then suspended in water, typically 1% wood fibre to 99% water. The resulting stock is pumped to the headbox of the papermaking machine. The headbox disperses the fibres so that they can be propelled to the forming section in a thin stream, up to 35 ft wide, at a speed of up to 60 mph. In that section the jet of stock lands on a belt of fabric which is travelling at the same speed as the jet. Thereafter it is drawn by the fabric over a series of blades designed to keep the fibres dispersed and act to remove some of the water so that by the end of the forming section the stock has been transformed into a web of paper fibre containing over 80% of water. It therefore has little structural integrity and must be supported. The web is then separated from the forming fabric and transferred to a wet press felt which proceeds through the press section. That section contains large rolls that squeeze the web and supporting felt so as to reduce the water content. From there the web is transferred to the drier section. At the point of transfer the water content has been reduced so that the web only contains 50 - 68% of water. It is still very weak. It is therefore supported by a fabric felt or felts as it passes through the dryer, where it is dried by contact with the outer surface of a series of steam-heated dryer cylinders so as to reduce the water content to between 2 - 10%. The paper is then sized, calendered, coated and wound on a reel.

To understand the patents and the issues involved, it is necessary to have some knowledge of the background to the design of dryer sections which form the essential part of the patents. That background was precisely set out by the Judge and as his account was not criticized by either of the parties I gratefully adopt it.

"I can pick up the history of dryer sections from l975 onwards. By then the general structure consisted of two horizontal rows of heated rollers. One row was above the other and the centres of one row were halfway between the centres of the other in the horizontal direction. The web was wound in sinusoidal or (slalom) manner from roller in one row to the other. It was supported as it went round the rollers by a felt which held it against the roller.

Two felts were used, one for the upper row and one for the lower. The felt itself was made of a continuous loop and passed over a series of rollers. The arrangement is often described as 'doubled-felted'."

Appendix 1 appended to this judgment is a diagram of such a system.

"In this case it will be seen that the web is unsupported as it passes from one row to the other. Typically that unsupported length is 3 - 6 ft. It is called an 'open-draw'. An open-draw can permit the web to shrink across the machine direction which is undesirable. More seriously an open-draw brings the problem of 'flutter' as machine speeds increase. The web carries air along with it and flaps about, almost like a flag in a breeze. Being fragile, especially at the wet end, flutter can cause the web to break. Then the machine has to be stopped, the broke web removed (such web is called 'broke') and the machine 're-threaded'. In the l970's paper speeds were of the order of 900 - 1000 m/min for newsprint. At this sort of speed flutter was a problem.

A simple solution emerged: avoid open-draw by supporting the web with a felt. In other words the felt went sinusoidally with the web. The system is called 'single-' or 'slalom-' or 'serpentine-' felted."

Appendix 2 to this judgment is a diagram of such a single-felted arrangement showing the felt winding around two tiers of cylinders, an arrangement adopted by Valmet under the name Uno-run.

"A particular advantage of single-felting was that it could be retro-fitted to existing machines. For each section concerned one did away with the lower felt and provided a new, slalom, felt. Single-felting was first introduced only for the end near the press section - where the paper is wettest and weakest. Double-felting continued to be used further down the line. It provides greater heating for a given length. By then the web was strong enough to withstand the flutter in the open-draw from one row of dryers to another.

Now a potential disadvantage of single-felting is that the web is on the outside of the felt as it goes round the lower rollers. So it is not in direct contact with them and some heating is lost. I was told that some mills on their own initiative decided to drop heating the lower rollers. This was not as serious a drawback as all that because the web could still dry, exposed as it was to the air.

An advantage of single-felting was also the opening of the system up to better air-flow. With double-felting the air between the felts tended to be trapped which was not good for drying. Single-felting avoids this trap. Also, because in the upstream stage, the felting is from the top, if the web broke it was relatively easy to clear the machine. The broke could fall into the basement.

With the introduction of single-felting (and other improvements in other parts of the machine) speeds went up, bringing yet other problems. In particular air tended to get through the felt as it passed from upper to lower row, separating the web from the felt fabric. This is called 'blowing'. It should always be remembered that one is considering here substantial air velocities - near gale. In l981 Valmet introduced 'blow boxes' to deal with this. These were devices inserted just above the lower dryers close to the web/felt which blew air outwards, thereby creating a partial vacuum in that area. This helped reduce blowing. Speeds continued to grow, partly due to this and partly to other improvements. It was an advantage of the blow-boxes that they could be retro-fitted to existing machines. They remain of immense use.

In l983 Beloit introduced a specially designed single-felt type of dryer which they called the Bel Run. Instead of using standard dryer rolls in the lower section, smaller rolls are used. This enables the dryer rolls to be closer together, having the advantages that the web can be kept in contact with the upper rollers for a larger arc and that the inter-roller distance (vertically) is reduced. But smaller rollers have to rotate faster and the centrifugal force is proportional to the square of the angular velocity. So the smaller rollers more readily tend to throw the web (which is on the outside) off. To keep the web on the felt and to prevent air-build up in the 'nip' region (where the web/felt approached the lower roller) Beloit therefore used 'suction rollers' for these lower rollers. These were a relatively expensive type of roller which had holes in its surface and an internal system for creating a vacuum - the air being drawn out through the journal. The suction created a centripetal force to counteract the centrifugal force."

Appendix 3 to this judgment is a diagram of a Bel Run system showing one section of single-felted cylinders upstream of a conventional section with a double row of dryer cylinders.

"It will be seen that the Bel Run is top-felted, just as in the other slalom-felted dryers. It was used upstream only, there being a point when the system changed to a conventional double row of dryers when the web was strong enough. Moreover, and this is important, it was recognised that the Bel Run only heated one side of the paper. This, if not corrected, would lead to 'curl', a tendency of the paper to curl. The danger of creating curl only arises as the web becomes drier: when it is still very wet it does not retain a 'memory' of the dryers it has passed around. Of course in a conventional double-felted section the web is heated on alternate sides as it passes from dryer roll to dryer roll. It will be noted that the web is supported throughout the Bel Run portion. For the most part the support is by a felt, though there is a short unfelted section as it passes from one section to another. However the web is supported by a dryer roller over this section. But once the web went on to the conventional two-row system (with two felts) it was no longer always supported - there was an open-draw between the upper and lower rows.

Valmet also decided to make special single-felted machines - in about l985. They did not use the small type of suction roll in these. They did not and do not like them. They think larger rolls are better. The web has a longer path to travel and so can evaporate more, and there is less centrifugal force. In l984-5 they introduced the use of a special form of these which they called Uno-rolls. These were grooved and used in conjunction with suction boxes. They were cheaper than Beloit's suction rolls. The vacuum in the grooves helped keep the web (on the outside of the felt) on the roll."

Thus by the priority date of the patents Beloit had moved to the Bel Run design: at the upstream end sections of a single tier of cylinders, suction guide rollers underneath and top- felted followed by a two tier top and bottom-felted section. Valmet's alternative was the Uno Rolls: two tiers of drying cylinders with the bottom row grooved, top-felted and blow boxes.

A. Patent 899

The specification begins with a description of the prior art. It first refers to the German patent of Soininen. The most relevant embodiments of that patent are said to be those shown in figures 5, 6, 8 and 9. Those embodiments are criticized because they do not include means for holding the web against the respective dryer felt while the dryer felt passes around the guide rolls. It is said

"Thus there is a danger for the web to become separated from the respective dryer felt. Moreover the above-mentioned embodiments do not include means for completely avoiding an open-draw in the web transfer sections. As a result the web in the web transfer sections is susceptible to breaks."

Thereafter the specification refers to the US patent no. 4359 827 of Thomas. The apparatus disclosed in Thomas is said to comprise a series of upper dryer drums and a series of lower grooved dryer drums. It is said that such an arrangement suffers from the defect that as there is no direct contact between the lower dryer drums and the web any drying of the web during passage around the lower dryer drums is greatly reduced. In order to hold the web against the fabric, vacuum boxes are provided between the upper and lower dryer drums. There is also a suggestion that the lower dryer drums can be replaced with cylinders having foraminous major surfaces. A vacuum is supplied so that the vacuum evacuates the grooves or the interiors of the foraminous cylinders thereby holding the web and fabric combination together onto the cylinder outer surfaces. That arrangement is criticized as it said there is no suggestion that the foraminous cylinders should have a diameter smaller than the dryer drums. Thus the foraminous cylinders cannot be placed sufficiently close to the dryer drums to avoid a long fabric draw between the consecutive dryer drums. Further, as a result of the vacuum boxes between the higher drums and the lower drums, wear will occur whenever the fabric comes into contact with the vacuum boxes because they have a stationary rigid surface.

The specification goes on to refer in outline to the Bel Run arrangement and the known single-felted dryer sections and draws attention to their deficiencies in this way:

"In the aforementioned Bel Run configurations and single-felted dryers, problems exist in that only one side of the web is dried during passage of the web through the first few groups of dryers. Consequently, such arrangement results in differences in surface strength and properties. Additionally, the smoothness of the respective surfaces of the web differ which is a problem when a sheet is required in which both sides of the sheet must have similar characteristics. Also, curl and non-uniform response to change in humidity have been problems with the aforementioned dryer sections."

The object of the invention is described in this way.

"An object of the present invention is to provide an apparatus and a method that overcome the aforementioned inadequacies of the prior art of drying apparatus and which permit a positive transfer of the web between successive groups of dryers in a non-open-draw configuration such that alternate sides of the web can be dried thereby providing a paper product having uniform surface characteristics, surface strength and smoothness, and no tendency to curl."

The invention is described in the body of the specification with the aid of three figures which are appended to this judgment. Figure l shows the known Bel Run configuration with four drying sections, the first three of which consisted of three drying cylinders and three suction transfer rolls. Figures 2 and 3 show the invention. Again the dryer is shown as having four sections with three drying cylinders and three suction transfer rolls in each section. There are however two important differences between the arrangement shown in figures 2 and 3 and the arrangement of the Bel Run shown in figure l. In figures 2 and 3 the even-numbered sections have their dryer cylinders and suction transfer rolls inverted so that the suction transfer rolls are above the cylinders. With such inversion, if the dryer cylinders of the second section are rotated in the opposite direction to that of the first section, the web is dried by contact with the drying cylinders on both sides. Transfer from one section to the other is by means of a transfer section. This is provided by an extra suction roll at the end of the each section which is positioned so as to provide a sandwich to ensure that the web is transferred to the felt of the downstream section whilst at all times being supported. Thus inversion, (bottom felting,) ensures that the other side of the web comes in contact with the drying cylinder and the sandwich, provided by the suction transfer rolls, ensures transfer from one felt to another with support.

The specification ends with l0 claims. Claim l is no longer defended but it needs to be considered as claim 2 is appendant to it. These claims, split up into integers, are as follows:

1. An apparatus for drying a web (1A)

2. said apparatus comprising a first single tier dryer section (A1)

3. having a first plurality of dryer drums (2A, 2A', 2A")

4. rotating in a first direction 20)

5. for drying a first side (8A) of the web (1A)

6. said first dryer section (Al) including a first plurality of suction rolls (3A', 3A")

7. rotating in a second direction (22) opposite to said first direction (20)

8. said suction rolls (3A', 3A") being disposed between adjacent dryer drums of said first plurality of dryer drums (2A, 2A', 2A")

9. first dryer felt means (4A) for conveying the web (1A)

10. in a serpentine path along said dryer drums (2A, 2A', 2A") and said suction rolls (3A', 3A")

11. a second single tier dryer section (Bl)

12. disposed downstream relative to said first dryer section (A1)

13. and having a second plurality of dryer drums (6A, 6A', 6A")

14. rotating in said second direction (22)

15. for drying a second side (9) of the web (1A)

16. said second dryer section (Bl) including a second plurality of suction rolls (7A', 7A")

17. rotating in said first direction (20)

18. and disposed between adjacent dryer drums of said second plurality of dryer drums (6A, 6A', 6A")

19. second dryer felt means (4A') for conveying the web (1A)

20. in a serpentine path along said second plurality of dryer drums (6A, 6A', 6A") and said second plurality of suction rolls (7A', 7A")

21. and means (3A", 5A, 7A, 12) for guiding said first and second felt means (4A, 4A')

22. in close proximity to each other between said first and said second dryer sections (A1, Bl)

23. so as to sandwich the web (1A) between said first and said second felt means (4A, 4A')

24. to effect a controlled transfer of the web (1A)

25. from said first felt means (4A) to said second felt means (4A').

1. An apparatus as set forth in claim 1

2. wherein said means for guiding said first and said second felt means in close proximity to each other include a first suction roll (3A")

3. disposed downstream relative to said first plurality of dryer drums (2A, 2A', 2A")

4. and a second suction roll (7A) disposed downstream relative to said first suction roll (3A")

5. said first suction roll (3A") being operable to apply a vacuum to said web (1A)

6. through said first felt means (4A)

7. to hold said web (1A) against said first felt means (4A)

8. while said web and said first felt means pass jointly around said first suction roll (3A")

9. said second suction roll (7A) being operable to apply a vacuum to said web (1A)

10. through said second felt means (4A')

11. to hold said web (1A) against second said felt means (4A')

12. when said first felt means (4A) separates from the web (1A)

13. so that the web (lA) is transferred

14. without open-draw

15. from said first felt means (4A) to said second felt means (4A')

16. and when said second felt means (4A') and said web (1A) pass jointly

17. around said second suction roll (7A).

The complexity of those claims can in part be dispelled by taking the integers in groups. The first group, relating to the single tier dryer section, has the features of integers 2 - 10 of claim 1. In essence what is claimed is a single tier dryer section of the Bel Run type. The second group, integers ll to 20, claim a second single tier dryer section similar to the first group, but inverted so that the suction rollers are above the drying rollers with the result that the other side of the web is dried. The third group, integers 21 to 25, cover features relating to the way that the web, moving from the first dryer section, is transferred to the second. Claim 2 claims, in more detail, features of the transfer mechanism. In essence there is positive transfer using appropriately positioned suction rolls.

A.1 Is claim 2 novel of UK Patent 4359 827 (Thomas)?

Figure 6 of Thomas is the disclosure relied on by Valmet as anticipating claim 2 of the patent. It is appended to this judgment as appendix 5. That figure is described in column l5 at line l5 in this way:

"The web W travels about the dry drum 23" supported on the fabric ll0'. As the web leaves the drum 23", fabric 200' is brought into contact with it. The web, now sandwiched between fabrics 110' and 200', travels across suction boxes ll2' and ll4'. The pressure differential between the two suction zones of the boxes is adjusted so that the web transfers from adherence to the fabric ll0' onto fabric 200'."

The drums are preferably provided with a plurality of shallow circumferentially spaced grooves cut in the outer surfaces of the drums. It is the resulting pressure differential induced in the grooves on the drums by the vacuum boxes which holds the web to the fabric. The specification also states as one of a number of ideas:

"The grooved, heated lower cylinders may, as an alternative, be replaced with cylinders having foraminous major surfaces. For example, the bottom of the grooves 40 and shown on figure 5 of the cylinders may be appertured about their circumference. A vacuum on the cylinder interior then evacuates the grooves thereby holding the web and fabric combination together onto the cylinder out of surface, independent of centrifugal or other velocity stresses. The foraminous cylinder may be of relatively light-weight construction since it does not have to withstand conventional steam pressures."

"To anticipate the patentee's claim the prior publication must contain clear and unmistakeable directions to do what the patentee claims to have invented. ... A signpost, however clear, upon the road to the patentee's invention will not suffice. The prior inventor must be clearly to have shown to have planted his flag at the precise destination before the patentee." ( General Tire & Rubber Co v Firestone Tyre & Rubber Co Ltd (1972) RPC 457 at 486)."

The Judge, having considered Thomas, identified three grounds for concluding that there was no anticipation. He said:

"Firstly then, are these foraminous cylinders 'suction rollers'? And, if they are, are there clear and unmistakeable instructions to use them in the figure 6 construction? For the reasons I have already given, I think they are not suction rollers.

Moreover I do not think that one can fairly say that there are clear and unambiguous instructions in Thomas to build figure 6 using his foraminous cylinders. Thomas has too many ideas altogether in the same patent. He spells out a number of different possibilities and only with hindsight can one focus down and say: "While taking this possibility with that possibility one has such instructions." I see that the opposition division of the EPO has taken this view.

There is a further point about Thomas figure 6. As I have indicated, the method of transfer depends not only on a sandwich as such but upon a pressure differential between his boxes. This ensures the transfer from one felt to the other. He does not seem to have realised that transfer from one felt to the other can be achieved without such differential pressure."

The Judge's conclusion that the foraminous cylinders were not suction rollers was based upon his construction of those words in the claim. He held that the words "suction rollers," which were synonymous with vacuum rollers, had in l986 a technical meaning which did not include the foraminous rollers of Thomas. He also said that there was particularly good reason for not regarding a roller having foraminous major surfaces as a suction roll. Thomas which discloses foraminous rollers does not call them suction rollers, but does refer to other rollers as vacuum rollers.

Valmet submitted that the words "suction rollers" did not have a technical meaning in l986 and that use of any roller that applied suction fell within the claim. They relied on the evidence of Mr Mackay. Beloit supported the Judge. They referred to the evidence of Mr Wedel who said that in l986 the only suction rollers that were on the market had the vacuum applied at their ends and he would not, at that date, have regarded the foraminous rollers of Thomas as suction rollers as claimed.

Having read the evidence of the experts I am not certain that I would have interpreted the words "suction rollers" in the way that the Judge did. It is however unnecessary for me to come to any conclusion to the contrary as I believe that the Judge was right to conclude that Thomas was not an anticipation for the other reasons given by the Judge.

The passage in Thomas which suggests the use of foraminous cylinders states: "The grooved, heated lower cylinders may, as an alternative be replaced with cylinders having foraminous major surfaces." To anticipate it is necessary in figure 6 to replace the lower rollers of the first section and the upper rollers of the second with foraminous cylinders. That may be an obvious, alternative to what is described in Thomas, but it does not amount to clear and unmistakeable directions to do that which is claimed.

Secondly, the last integers of claim 2 require the second suction roll to hold the web against the second felt when the first felt separates from the web. In Thomas it seems that the transfer is achieved by the pressure differential between the vacuum boxes.

I therefore endorse the Judge's conclusion that claim 2 was not anticipated by Thomas.

A.2 Is claim 2 obvious?

As stated by Sir Donald Nichols VC in Monlyke AB v Procter & Gamble Ltd (1994) RPC, 49 at 112:

"Under the statutory code (which is further confirmed in its completeness by sections 74 and 72) the criterion for deciding whether or not the claimed invention involves an inventive step is wholly objective. It is an objective criterion defined in statutory terms, that is to say whether the step was obvious to a person skilled in the art having regard to any matter which forms part of the state of the art as defined in section 2(2). We do not consider that it assists to ask whether the patent discloses something sufficiently inventive to deserve the grant of a monopoly. Nor is it useful to extract from older judgments expressions such as 'that scintilla of invention necessary to support a patent.' The statute has laid down what the criterion is to be: it is a qualitative not a quantitative test. The warning against coining phrases given by the Court of Appeal in General Tire Rubber Co ... is even more apt under the l977 Act (see also the rejection of semantic arguments by the Court of Appeal in Hallen v Brabantia (1991) RPC 195 at 211 - 212).

The Act requires the court to make a finding of fact as to what was at the priority date, included in the state of the art and then to find again as a fact whether, having regard to that state of the art, the alleged inventive step would be obvious to a person skilled in the art."

That question of fact is a jury type question which inevitably requires the Court and usually the witnesses to look back with knowledge of the invention. Such an advantage was not available to the inventor and therefore, when deciding the jury type question, the Court must be careful not to be wise after the event. The Court must put on 'the spectacles' of the notional skilled addressee at the priority date of the patent and, using such contemporary evidence as there may be, make sure that any conclusion reached is not the result of hindsight.

As stated in section 3 of the Patents Act l977 the invention, to be patentable, must not be obvious to "a person skilled in the art." That person is the notional addressee of the patent. He lacks inventive capacity, but is deemed to have the common knowledge in the field to which the invention relates. That knowledge has come to be called the common general knowledge in the art.

It has never been easy to differentiate between common general knowledge and that which is known by some. It has become particularly difficult with the modern ability to circulate and retrieve information. Employees of some companies, with the use of libraries and patent departments, will become aware of information soon after it is published in a whole variety of documents; whereas others, without such advantages, may never do so until that information is accepted generally and put into practice. The notional skilled addressee is the ordinary man who may not have the advantages that some employees of large companies may have. The information in a patent specification is addressed to such a man and must contain sufficient details for him to understand and apply the invention. It will only lack an inventive step if it is obvious to such a man.

It follows that evidence that a fact is known or even well-known to a witness does not establish that that fact forms part of the common general knowledge. Neither does it follow that it will form part of the common general knowledge if it is recorded in a document. As stated by the Court of Appeal in the General Tire case at page 482, line 33:

"The two classes of documents which call for consideration in relation to common general knowledge in the instant case were individual patent specifications and 'widely read publications'.

As to the former, it is clear that individual patent specifications and their contents do not normally form part of the relevant common general knowledge, though there may be specifications which are so well known amongst those versed in the art that upon evidence of that state of affairs they form part of such knowledge, and also there may occasionally be particular industries (such as that of colour photograph) in which the evidence may show that all specifications form part of the relevant knowledge.

As regards scientific papers generally, it was said by Luxmoore, J in British Acoustic Films (53 RPC, 221 at 250):

"In my judgment it is not sufficient to prove common general knowledge that a particular disclosure is made in an article, or series of articles, in a scientific journal, no matter how wide the circulation of that journal may be, in the absence of any evidence that the disclosure is accepted generally by those who are engaged in the art to which the disclosure relates. A piece of particular knowledge as disclosed in a scientific paper does not become common general knowledge merely because it is widely read, and still less because it is widely circulated. Such a piece of knowledge only becomes general knowledge when it is generally known and accepted without question by the bulk of those who are engaged in the particular art; in other words, when it becomes part of their common stock of knowledge relating to the art."

And a little later, distinguishing between what has been written and what has been used, he said:

"It is certainly difficult to appreciate how the use of something which has in fact never been used in a particular art can ever be held to be common general knowledge in the art."

Those passages have often been quoted, and there has not been cited to us any case in which they have been criticised. We accept them as correctly stating in general the law on this point, though reserving for further consideration whether the words 'accepted without question' may not be putting the position rather high: for the purposes of this case we are disposed, without wishing to put forward any full definition, to substitute the words 'generally regarded as a good basis for further action'."

In this case the Judge rightly adopted the structured approach suggested by Oliver LJ in Windsurfing International Inc v Tabur Marine (1985) RPC 59 at 73. Unfortunately he adopted the summary set out in Monlyke which, if one does not not have in mind what Oliver LJ said, can mislead. Oliver LJ said:

"There are, we think, four steps which require to be taken in answering the jury question. The first 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 in the art at the priority date and to impute to him what was, at that date, common general knowledge in 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."

Mr Thorley who appeared for Beloit submitted that the judgment of the Judge contained three basic misconceptions. First the Judge failed, when considering what was obvious, to differentiate between the two types of single felted dryers, namely the single tier Bel Run type dryers and the double tier machines of which the Uno Run was an example. Second the Judge wrongly concluded that the concept of inversion by group formed part of the common general knowledge. That concept was, he submitted, a paper curiosity that had never been used. Third, the Judge's conclusion was marred by hindsight. I will deal with those submissions as they arise when considering the issue of

obviousness using the structured approach suggested in Windsurfing.

(a) What is the inventive concept embodied in the patent?

The Judge said:

"In both patents it is broadly the same. Both patents acknowledge, inter alia, the Bel Run as prior art, the problems caused by one-sided drying (curl), the desirability of drying on alternate sides and the problems associated with open-draws. The solution is inversion of dryer groups using a transfer of two suction rolls to provide a felt-web-felt sandwich, thus avoiding an open-draw."

Neither party criticised the substance of that conclusion. The Judge was in my view right. The Bel Run solution is used to eradicate open-draw with a change to bottom felting (inversion) to dry the other side of the paper. Suction rolls produce positive transfer.

(b) Adoption of the mantle of the skilled addressee so as to clothe him with the common general knowledge.

Mr Thorley submitted that the Judge misunderstood the second step of Windsurfing when he characterised it as "What was the state of the art?" He submitted that he then failed to distinguish between what was known to some designers from what was common general knowledge. He also criticised the way that the Judge considered in this part of his judgment what the skilled addressee would take from Thomas and Soininen.

That criticism is to an extent justified in that the Judge appears to have elided step 3 of Windsurfing with step 2. However he did itemise ll matters which he held to be common general knowledge. No substantial criticism was directed at items 1 - 10. I can therefore concentrate on item ll which was as follows:

"11. The concept or idea of inversion of a group of dryers to dry the other side of a web was known to designers.

I am quite satisfied that this is so on the cross-examination of Mr Wedel. For example he accepted he knew of a Beloit patent (Mahoney) which showed this, that a Mr Edgar had mentioned that patent in a widely-read journal. There were a number of other proposals put to him which also showed inversion. In the end his evidence boiled down to this: that the concept was well-known but no-one had actually done it."

Mr Thorley submitted that the evidence established that inversion by group had never been used in a machine of the type disclosed in the patent. It had, he accepted, been proposed in three patent specifications none of which disclosed a practical machine. He also accepted that it had been mentioned in two articles with the result that the best informed, such as Mr Wedel, knew of the concept. But he submitted that did not establish that the concept was part of the common general knowledge.

Mr Kitchen, who appeared for Valmet, accepted that prior to Beloit producing machines using the invention, inversion in a single felted machine to dry the other side of the web had never been put into practice, but that he submitted was not material. A concept could form part of the common general knowledge even if it had not been put into use and the Judge was right to hold

that the cross-examination of Mr Wedel did establish that the concept formed part of the common general knowledge.

When deciding whether something forms part of the common general knowledge the first and most important step is to look at the sources from which the notional skilled addressee could acquire his information. Such sources can vary from instruction at university to description in obscure patent specifications. Whatever the source, it is necessary to have in mind the observations of the Court of Appeal in General Tire . I accept Mr Kitchen's submission that the mere fact that the concept of inversion by group had not been used does not mean that it could not form part of the common general knowledge, but it makes it unlikely. I therefore turn to the sources from which the notional skilled man could have obtained his knowledge. Inversion by group is shown in three patents. The first is the l970 US Patent 350 3139 of Mahoney. That showed a two tier arrangement with the first section having a top felt and the adjacent section with a bottom felt. That construction was referred to in an article in 'Paper Trade Journal' of l5 January l977 written by Clement Edgar which drew attention to the advance made by single felting and in particular the Uno Run machine. It said:

"In l968, Mahoney patented a scheme for improved drying and web stabilisation (fig 2). In this patent the concept of a single dryer fabric covering both top and bottom dryers was introduced in conjunction with a high velocity, high temperature air cap. The idea involved utilisation of high velocity, high temperature air to compensate for the loss in drying that would occur with the fabric insulating the sheet from the hot dryer.

The Mahoney patent contemplated use of the bottom fabric, which included top dryers (reverse Uno Run) alternating with the top fabric, which included bottom dryers. These ideas were never tried commercially to our knowledge, possibly because of the high capital cost. Also it does appear to us that there would be broke removal problems - especially with the reverse Uno Run."

The Mahoney patent was followed by the l975 US patent No 3868 780 of Soininen which was assigned to Valmet. That contains

nine figures and figures 5 - 9 show inversion of groups. Figure 9 is appendix 6 to this judgment.

The US patent of Thomas which was assigned to Weyerhauser Co was published in l982. That also showed inversion.

Finally there is the Linderott article published in August l986 in Wochenblatt Fuer Papierfabrikation. That article reviewed l0 years experience with closed web guidance. It ends with ideas for further development and concludes:

"If one wants to exhaust all avoidable possibilities for increasing the speed it is impossible to avoid using closed guidance, even if the dry content after the presses can be increased up to 50%. It is much more likely that closed guidance will be necessary at speeds above 1300 m/min in all drying groups. In certain types of paper this may require close guidance to be installed alternately above and below to avoid two sidedness."

The evidence established that inversion by group had not been put into practice before to the priority date of the patent. Mr Wedel, the inventor, knew of Mahoney, Thomas and Soininen. He accepted that the concept of inversion of the type shown in two tier two felt dryers was well-known. That of course is not inversion in the sense in which the word has been used in this case to denote inversion of a single tier group. He also accepted that engineers within the industry would have seen some of the patents. The Judge's conclusion was based upon this passage in his cross-examination. (Evidence 3, ll4)

Q. And that inversion was well-known as a concept of groups?

A. But, again, as I suggested, never practised to my knowledge, so there were with it corresponding concerns.

Jacob J: I think Mr Kitchen's question was: Was it well-known? I think you qualified it by saying, in effect, that it had never been done, but it was known. Is that right?

A. That is what I had said, Yes.

Taking Mr Wedel's evidence as a whole it is clear that he obtained his knowledge of inversion by group from the patents and that he was of the view that engineers knew of that concept.

Valmet called Mr Mckay as an expert witness. He was an engineer who had worked in the paper industry since l948. He started with Alex Pirie and soon became involved in modernising paper machinery. He moved to Reed & Smith and then on to a subsidiary of the Spicer Paper Group where he worked as Chief Engineer. In l969 he joined an American firm of Consulting Engineers to the paper industry and in l982 set up his own consultancy. I would have expected him to be aware of the concept of inversion by group in the particular field if it was common general knowledge.

In his statement Mr Mckay said that the concept of inverting single felted dryer groups had been known for a long time. That was challenged in cross-examination. It appeared that before becoming concerned with the action he had not seen Mahoney, Thomas, Soininen, or Linderott. He may not have seen Edgar. He was asked: (Ev 4 at 149).

Q. ... When you say: '... the concept of inverting single felted dryer groups having been known for a long time' you are not pretending that that was known to the man as being part of the tools of the trade of a newsprint dryer design.

A. No. I would think any self-respecting paper mill machinery manufacturer must know of other machines irrespective of whether he is trapped in newsprint or what have you. Here we are looking at newsprint which I still say is rubbish and it is limited as to how much correction you have to do because of the so-called curl problem. You only keep a newspaper for 24 hours and you are not worried. Certainly you cannot turn the sheet of paper on its back so you have to turn the machine on its back to invert part of the machine. I am saying that I had seen the concept with bottom felting.

Q. You have if I may respectfully say so a very eclectic background in paper-making machines.

A. I have been around a lot longer than some of the others, Yes.

Mr Mackay's knowledge of inversion appeared to come from cigarette paper-making machines and perhaps an article which he was unable to identify. There is no evidence to suggest that persons like Mr Wedel would have knowledge of such machines.

Taking the evidence as a whole, it appears that inversion by group was part of the state of the art as it had been published. Further, a number of persons skilled in the art would have read the patents which used it and were familiar with the concept even though it had not been put into practice. But those who had not read the patents, perhaps because they worked for Companies without a patent department, would not know of the concept unless they had experience outside the field of newspaper print production. The concept was well-known to some, but it was not shown to form part of the common general knowledge in that the evidence did not establish that the concept was known to the bulk of those skilled in the art, let alone that it had been accepted without question by them.

In my view the Judge was right to hold that "The concept or idea of inversion of a group of dryers to dry the other side of the web was known to designers". However he was not right to go on to conclude from that that it had been established that it formed part of the common general knowledge.

There is no dispute as to the other matters which were part of the common general knowledge. As set out in the judgment of the Judge, the notional skilled addressee would know of the history starting from single felting in the mid-l970's through to the Uno Run. He would have been aware of the difficulties that open-draws could produce. He would be familiar with felts, suction rolls, drying rollers, and all the mechanical parts needed to make the invention.

C. What are the differences between the pleaded prior art and the alleged invention?

Before us the only prior art relied on, other than the Bel Run, were Soininen and Thomas. I have already considered Thomas which discloses inversion by group. The difference therefore is the use of suction rolls and using them for positive transfer.

The most pertinent figure in Soininen is appended to this judgment as figure 6. The web moves from right to left and is guided by felt 8 so as to be heated on one side. After two drying rolls the web is transferred to another felt 8 so that the other side of the web comes into contact with the next three drying rolls. The procedure is repeated. That transfer avoids open-draw. The difference between the invention of claim 2 and Soininen is the use of suction rolls.

The invention in the patent is described and shown as an improvement over the Bel Run which had been disclosed in l983 and installed in l985. The notional skilled addressee would know of its construction and at the priority date of the patent would consider it and the Uno-Rolls to be the most modern dryers on the market. The difference between the Bel Run and the invention as claimed in claim 2 was inversion by group and positive transfer. Mr Thorley submitted that the conclusion reached by the Judge in the passage of his judgment which dealt with the differences between the prior art and the inventive concept led him into error. The Judge said:

"So far as common general knowledge is concerned the inventive step hardly differs at all. It amounts to continuing single felting to the end of the dryer section (a logical development) but using inversion of groups (a known concept) to dry on alternate sides (namely to avoid curl), the inversion being achieved by sandwich transfer.

In relation to Thomas I think a skilled man, aware of the Bel Run and the fact that in single felted groups the lower dryers provided so little heat that some mills turned it off, would readily have recognised that only a single tier of heated rollers would be necessary. He would also have got that from Thomas's suggestion of foraminous rollers. I also think those would suggest vacuum rolls even though they are not strictly such. He would also see a sandwich transfer - a way of using two felts to protect the web as it was transferred from one group to another. I am confirmed in my belief that that is what the skilled man

would see because that is actually what I think happened in the case of Mr Wedel. I do not think the skilled man would be put off by Thomas's special differential pressure. The sandwich transfer is clear to see.

As to Soininen, again a sandwich is shown in many of the figures. But the rollers shown are not suction rollers."

Mr Thorley made three criticisms of the first paragraph of that part of Jacob J's judgment. First he pointed out that continuation of single felting to the end of the dryer would not have arrived at the claimed invention which was limited to single tier dryer sections. That criticism is of course right, but it may be, as Mr Kitchen submitted, that the Judge really meant "Single tier, single felting."

Second Mr Thorley submitted that the Judge wrongly believed that the concept of inversion by group was part of the common general knowledge. Third, that even if inversion was achieved with sandwich transfer that would not mean that claim 2 was obvious as it was limited to what I have referred to as positive transfer. That again is a valid criticism.

As to the second paragraph, Mr Thorley submitted that the Judge appeared to be adding features to Thomas and probably fell into the same error as in the first paragraph by equating sandwich transfer as being the positive transfer claimed in Claim 2 of the patent.

(d) Did the differences between the prior art and the invention constitute steps which would have been obvious to the skilled man?

The Judge held:

"I think the step from the common general knowledge was indeed obvious. I think it was the natural consequence of extending single-felting throughout the dryer, a step which only became worth considering about the time of the alleged invention. As soon as the open-draws of the double-tier became a problem the sensible thing to do is to get rid of them: single felting will achieve this as was well-known and the inversion of a group of dryers is a self-evident way to heat the other side of the web. I think the skilled man would have recognised that. He would naturally want to avoid an open-draw on inversion and so protect the web by a sandwich. Even if he did not think of this method of transfer himself, (as I think he readily would,) he would certainly get the idea from Soininen or Thomas. As for the use of suction rolls for the pick-up, that too would be self-evident - the point of these being to keep the web/felt together as was already being done in the Bel Run."

Mr Thorley criticised that passage. He submitted that the Judge had continued to concentrate on single-felting even though the patent was limited to single tier, single-felted dryer sections and in any case the Judge's view as to what was obvious was founded upon the wrong conclusion that inversion by group was part of the common general knowledge. He submitted that to take the idea of inversion by group from Soininen or Thomas was not logical having regard to their teaching and in any case there was no suggestion of positive transfer in any of the prior art. He drew attention to the fact that the basic idea disclosed in Soininen was to produce a space within the drying belt area to which a vacuum was applied. That being so, the idea of converting the guide rolls into suction rolls, although it appeared simple, would constitute a complete redesign which disregarded the disclosed method of applying suction to the felt. Similarly, with Thomas, the idea was to apply suction to the felt using vacuum boxes. No doubt with hindsight the grooved or foraminous rolls could be altered to suction rolls, but said Mr Thorley, nobody reading Thomas at the time would want to do that as it would be expensive and contrary to the essential idea of Thomas which was to use vacuum boxes.

Mr Kitchen submitted that when the judgment was read sensibly the conclusion reached was correct and inevitable. First, when open-draws of the double-tier at the end of the Bel Run became a problem it was obvious to get rid of them with a mechanism which would continue to heat the other side of the web to avoid curl. Second, the Bel Run idea using suction rolls was developed to avoid use of open-draw in two tier machines and therefore it was the obvious way to eliminate open-draws at the end of the Bel Run dryer. Thus extension of the Bel Run type mechanism to the end of the machine was obvious. Third, inversion by group was the self-evident way of heating the other side of the web. Fourth, positive transfer to eliminate open-draw from one group to another using suction rolls was part of the Bel Run and to do that between one group to an inverted group would be self-evident.

In my view the important point for decision is to decide whether it was obvious to change the Bel Run by including an inverted dryer section. If it was, then I believe it to be inevitable that the skilled man would have positive transfer. Suction rolls were a basic part of the Bel Run. They were used to hold the web onto the felt and were positioned so as to ensure transfer from one felt to another. It would be obvious to use them for transfer to an inverted group. How to do that would require design work, but that is not what is sought to be protected in claim 12.

As one would expect manufacturers of paper-making machines have, over the years, produced improvements which led to increased speed and reliability. In l976 the Uno Run was introduced which avoided open-draws within the sections and enabled easier removal of broke. It had disadvantages as the felt was between the web and the rolls when they passed around the bottom tier of heating rolls, thereby giving less drying heat to the web per unit length of machine. As speeds increased other problems ensued such as flutter, blowing and separation of the web from the felt due to centrifugal forces. Those were met by the introduction of Blow Boxes in l98l and vacuum boxes with grooved rollers in l985.

The Valmet dryer was not the only improvement made to paper-making machines by the industry. Improvements were made to other parts such as the press transfer mechanism and also to the felts. That was the position when the Bel Run was installed in l985. According to Mr Wedel it had advantages and was the most modern machine on the market at the time. As Mr Wedel accepted (Evidence 2, page 90) the problems at the wet end had been substantially improved when the Bel Run had been introduced to the market. "The continuing concern, however, was that the problems then appeared in yet the next section."

As installed the Bel Run had single tier single-felting sections at the upstream end which were followed by a series of two tier dryer sections with open-draw at the other end (see figure 3 appended to this judgment). It was clear that improvement was necessary to remove the open-draw in those last few sections without losing their advantages of heating the other side of the web. Thus the two tier sections were obvious candidates for improvement.

Mr Wedel accepted (Ev. 2/93) that with the increase of speeds it was plain that the two felt sections at the end of the Bel Run could be a problem due to open-draw. He also said that, subject to the need to redesign the tail threader, it would have

been logical to extend the single felt sections down the machine so as to avoid the open-draw at the end. He concluded that at the time he thought it was a logical, sensible and obvious to look at extending the Bel Run single tier sections down the machine. That would have used the Bel Run idea to eliminate the open-draws that were part of the two tier sections. All that remained was preservation of two sided drying and elimination of the open-draws at the point of transfer.

Mr Wedel was in l986 familiar with the concept of inversion by group to dry both sides of the web to avoid curl, but said that it had never been put into practice. That, Mr Kitchen submitted, was because the need to invert by group did not arise as a practical need until after the Bel Run had been introduced in l985. It was only at that time it became obvious to extend the Bel Run arrangement down the machine so as to avoid open-draw. If that was to be done whilst maintaining the desired drying on both sides, the purpose of the two tier sections at the end of the Bel Run, inversion was the obvious way to do it.

Mr Mackay was of the view that it was obvious to extend the Bel Run down the machine and to invert. The essence of his evidence was summed up in this answer, when he was being cross-examined about paragraph 95 of his statement which said that he believed it was plainly apparent to anybody in the field in l985, on the basis of his common general knowledge, that a way of dealing with the problem was to invert one or more of the single felted groups.

"I am saying that it is apparent to people in the field in l985. There are people in the field who are dealing with these single felted arrangements and that is mainly the machine makers. It must have been apparent to them in the field that they would have to reverse one or two of them."

Putting myself into the situation of the skilled man in l986 I have come to the conclusion that it was obvious to seek to improve the Bel Run by eliminating the open-draws at the downstream end of the machine. To do that the natural reaction would be to extend the single tier Bel Run arrangement down the machine. I also believe it was obvious to continue to heat the other side of the web and that that could best be achieved by inverting a group. In fact, all that would have to be done was to insert suction rolls into the bottom half of the double felted section used to heat the other side of the web. That would convert it into an inverted single tier Bel Run section. That that was obvious is, I believe, supported by the evidence. Further, the idea of inverting a group, albeit in a different type of machine, was adopted by Soininen and Thomas to achieve heating on the other side of the web. Is that a conclusion reached by being wise after the event?

There are I believe a number of factors which throw light upon that question, none of which are conclusive, but which together suggest that inversion by group was obvious as of l986.

First, the first Bel Run was installed in l985. Thus the need to alter the two tier sections at the end did not appear until about that time. Thus it cannot be said in the present case that the invention was not obvious as the problem which it solved had not been solved for a long time. The time sequence is not inconsistent with the claimed invention being obvious.

Second, inversion is used in Soininen and in Thomas for the same purpose as it is used in the patent, namely to heat both sides of the web. It is an idea incorporated into the constructions shown in those patents which is independent of the general teaching in them.

Third, Mr Wedel was not the only person to think of modifying a Bel Run arrangement using inversion by group. Mr Skaugen in a sketch dated l7 November l985 showed such an arrangement with positive transfer. Mr Skaugen could have arrived at his sketch from something said by Mr Wedel, but there is no evidence to show that he co-operated with Mr Wedel before May l986, that being the date of the first entry of his name in Mr Wedel's notebook. The inventors of 266, Mr Onishi, Mr Sakoda and Mr Mitsuoda also came up with improvement of the Bel Run using inversion. They could perhaps have obtained the idea from meetings between them and Beloit as MHI, their employers, were licensees of Beloit; but the fact that they applied for a patent in Japan suggests that they believed that they were the originators of the idea. Mr Wedel did not say that he told them nor that he obtained help from them to get to the invention. Mr Christensen of Manistique Papers Inc enclosed with a letter sent to Beloit in l984 an arrangement for a newsprint dryer section. The letter said:

"While not incorporated on the sketch, the sheet can be transferred so that drying can be accomplished on the top side of the sheet rather than the bottom side of the sheet with a vacuum felt roll transfer so that no open-draws ever exist although direction of dryer rotation would be reversed. In this way both sides of the sheet can be dried if necessary. No rope systems are required when the design details are corrected. The sheet is always in intimate contact with the dryer felt."

Fourth, Mr Wedel thought of the idea of inversion prior to l986, but at that time did not take any steps to patent it. It seems surprising if inversion was thought by him to be inventive that he took no steps to make a record of the invention at that time.

Fifth, on Wednesday, l9 February l986, Mr Wedel read Thomas and noted in his notebook that it disclosed "transfers". On Tuesday, 25 February l986, he started to draft the disclosure for use of the patent department of the transfer box showing inversion by group. It seems clear that Mr Wedel had in mind the inversion shown in Thomas when he recorded the invention. It is possible that there could be invention in selecting inversion out of Thomas, but the fact that others had over the years the same idea suggests to the contrary.

Sixth, the authors of 266 envisaged that inversion per se was not inventive as that patent suggests that the inventive step lay in the way that transfer was achieved.

Seventh, Mr Skaugen thought it was logical to invert by group as Mr Wedel accepted when Mr Skaugen's deposition was put to him in cross-examination (Ev 3, p43).

Q. He then says: 'And in that sense, that is when I drew the sketch here realising that we had to make some means to dry the paper on both sides. Up to now we have a single Bel Run, and then we are going to two tier, and in the two tier section you dry on one side, the bottom side, one side, the other side, and we wanted to maintain that so we did not want to change the way that we made paper, so we realised that we had to extend it to get the speed up, and then we had to invert in order to maintain some of these things that we already knew.

Q. Did you see that?

A. Yes.

Q. What I am putting to you is that that is entirely sensible and logical. Indeed it is the position I was putting to you yesterday, that in l985/86, with increasing speeds being a concern to the major manufacturers, it was logical and sensible to extend it to get the speed up so that you avoided the unsupported felt in the two felt section at the end of the dryer.

A. Yes.

Q. If you are going to do that, you say to yourself, "How am I going to deal with the two sidedness?" The way to deal with two sidedness is to invert.

A. The way to deal with two sidedness is to dry from the other side. That is correct.

Q. If you are going to do away with a two felted section at the end and run your Bel Run down to the end, the way to do it is to invert a group.

A. I believe that that is the right way to do it. Yes.

Q. And that is what Mr Skaugen thought.

A. Yes.

Q. The only question then is how do you effect the transfer between the two groups.

A. Yes.

Q. Do you do it in an open-draw or in a sandwich or some other way?

A. Yes.

Bearing in mind the need to avoid being wise after the event I have come to the conclusion that claim 2 was obvious. The need to eliminate all open-draws became apparent after the

introduction of the Bel Run in l985 and it was obvious to do that by extending the single tier single felt arrangement through the entire dryer section, and maintaining two-sided drying. The obvious way to do that was inversion by group. Thereafter positive transfer was the obvious choice in that it could be achieved by suitable adjustment and provision of suction rollers. I conclude, not without some hesitation, that the Judge came to the right decision. Claim 2 was obvious.

Mr Kitchen also submitted that claim 2 was obvious starting from Thomas and Soininen. That may be right if it be assumed that it was obvious to improve the Bel Run in the way which I have contemplated. If so, the submission adds nothing. If however it be assumed that it was not obvious to improve the Bel Run as contemplated, then I have grave doubts as to whether it would be obvious to modify Soininen or Thomas to make them into a claim 2 apparatus.

B. Patent 266

B.1 Is claim 12 obvious?

Claim l2 of 266 was accepted to be obvious if claim 2 of 899 was obvious. It follows that the issue of obviousness need not be further considered.

B.2 Does the Aylesford Mk I fall within claim 12?

As an invalid patent cannot be infringed, the question of infringement by the Aylesford Mk I does not arise. If it had, I would have arrived at the same conclusion as the Judge for the same reasons.

To arrive at the middle ground between literal and liberal construction required by the Protocol on Interpretation of Claims, purposive construction is necessary and the best approach is to use the questions suggested in Improver Corporation v Remington Consumer Products Ltd (1989) RPC at 69.

"(1) Does the variant have a material effect upon the way the invention works? If yes, the variant is outside the claim.

If no -

(2) Would this (ie that the variant had no material effect)

have been obvious at the date of publication of the patent to a reader skilled in the art? If no, the variant is outside the claim.

If yes -

(3) Would the reader skilled in the art nevertheless have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning was an essential requirement of the invention. If yes, the variant is outside the claim.

On the other hand, a negative answer to the last question would lead to the conclusion that the patentee was intending the word or phrase to have not a literal but a figurative meaning (the figure being a form of synecdoche or metonymy) denoting a class of things which include the variant and the literal meaning, the latter being perhaps the most perfect, best known or striking example of the class."

The variant in this case is the change from having an inverted group as the third group, as stated in claim l2, to a position further downstream as used in the Aylesford Mk I.

Would the reader skilled in the art have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning, namely that third meant third, was an essential requirement of the invention? For myself I believe that he would. The requirement that it be the third section which is inverted appears as the primary limitation in claim l2 which is appendant to claim ll. Without that feature I cannot believe that the claim would be seen as adding limitation. Thus the skilled reader would believe that the patentee intended that third meant third even though he would not know why that limitation had been introduced. In any case Beloit never established that it would have been obvious to a reader skilled in the art that the variant had no effect upon the way the invention worked.

B.3 If the Aylesford Mk I falls within claim 12, is it anticipated by the application for 899?

The conclusion reached makes it unnecessary for me to extend this judgment any more by considering Valmet's claim of anticipation by the Japanese application.

C. The Relief

Beloit sought to amend their Notice of Appeal so as to contend that, because the patents were still under opposition in the EPO, the Judge had no jurisdiction to order revocation of the patents, as he did, until those proceedings were concluded. That Amendment was resisted by Valmet upon the ground that the submission had not been raised before the Judge and therefore it was not open to Beloit on appeal.

This Court was reluctant to shut out the submission that the Judge's Order was in part ultra vires as it was based upon construction of the Patents Act l977 and, if right, would have a considerable impact upon the procedure in other cases that were likely to come before the Patents Court. We therefore heard submissions both upon the question of whether leave to amend should be granted and the issue of construction raised.

The issue of jurisdiction should have been raised before the Judge so that we would have had the advantage of the Judge's views upon it. However, I would give leave to Beloit to amend the Notice of Appeal because the issue is one of law; it only affects the relief granted and not the other issues considered by the Judge and it raises an important question of statutory construction. I therefore turn to the substance of the matter raised by amendment.

The Patents Act l977 was in part enacted to give effect to the European Patent Convention. That Convention amongst other things enables applicants to secure a European Patent having effect in selected Convention countries. The procedure provides for filing at the EPO in Munich, followed by examination, publication and grant. Article 99 of the Convention provides for belated opposition within nine months of the grant. If the patent is opposed, procedure set out in the regulations comes into effect to enable the parties to establish their cases. Thereafter the opposition is decided by the Opposition Division which has the power to reject it, allow it with an order revoking the patent or to allow amendments to validate it. The Convention also provides for an appeal to a Board of Appeal. An appeal has the effect of suspending any order made by the Opposition Division until after the appeal has been concluded.

The Patents Act l977 provides an alternative route to obtain a national patent starting with an application to the United Kingdom Patent Office and proceeding to examination, publication and grant. The fact of grant has to be published in the journal (see Section 24). It is at that stage that the Act treats granted European patents in the same way as granted National patents. That is accomplished by Sections 77(1) in this way:

"77(1) Subject to the provisions of this Act, a European patent (UK) shall, as from the publication of the mention of its grant in the European Patent Bulletin, be treated for the purposes of Parts I and III of this Act as if it were a patent under this Act granted in pursuance of an application made under this Act and as if notice of the grant of the patent had, on the date of that publication, been published under section 24 above in the journal; and -

(a) the proprietor of a European patent (UK) shall accordingly as respects the United Kingdom have the same rights and remedies, subject to the same conditions, as the proprietor of a patent under this Act;

(b) references in Parts I and III of this Act to a patent shall be construed accordingly; and

(c) any statement made and any certificate filed for the purposes of the provision of the convention corresponding to section 2(4)(c) above shall be respectively treated as a statement made and written evidence filed for the purposes of the said paragraph (c)."

The dispute turns on the construction of the next subsection which is in this form:

"77(2) Subsection (l) above shall not affect the operation in relation to a European patent (UK) of any provisions of the European Patent Convention relating to the amendment or revocation of such a patent in proceedings before the European Patent Office."

Beloit submitted that the effect of that subsection was to prevent the UK Courts from making any order which would affect the operation of the provisions of the Convention relating to amendment and revocation. It followed that an order for revocation during a period of opposition could not be made as it affected that operation. Valmet submitted that the subsection only preserved the operation of the proceedings stemming from the Convention. To appreciate the purpose of those submissions, it is necessary to return to the facts.

On 2 October l992 Valmet started belated opposition proceedings in the EPO to revoke 899. By letter of 5 October l993 solicitors acting for Beloit wrote to Valmet citing 899 as the basis of a potential claim. On 26 October l993 Valmet petitioned to revoke 899 and later that month started belated opposition proceedings in the EPO to revoke 266. In December l993 Beloit issued the writ in these proceedings alleging infringement of 899 which they subsequently amended so as to include an allegation of infringement of 266. Valmet counterclaimed for revocation of 266.

On 20 October l994 the Opposition Division held that 899 was invalid and ordered its revocation. Beloit appealed. On 28 April l995 the Judge held the patents invalid and ordered their revocation. Beloit appealed. On ll October l995 the Opposition Division upheld 266 but on an amended claim. Both Beloit and Valmet appealed.

Before the Appeal Boards of the EPO, Beloit have an opportunity to challenge the orders of the Opposition Division and to put forward amended claims. Thus it is possible that the Appeal Boards will reject the claim for revocation upon the basis of amended claims, being claims as amended which were never considered in these proceedings. Beloit accept that they could have sought amendment in this country, but wish to avail themselves of the indulgent approach of the EPO to amendment applications as opposed to the practice in this country which requires that the party seeking amendment should formulate the amendment he seeks at an early stage of the proceedings.

The position as it stands at the moment is that the patents, in so far as they relate to the United Kingdom, have been revoked by the order of Jacob J on consideration of the claims as granted. The effect of that order is to preclude Beloit from choosing the European route to amend the European patents (UK) in the opposition proceedings, although any amendment obtained will apply to patents in other designated countries. According to Beloit, the result of the order revoking the patents is that the operation of the provisions of the Convention, which give them the ability to amend has been affected. Thus revocation provided for in Section 72 of the Act, is excluded by Section 77(2) and the English Court has no power, whilst opposition proceedings are before the EPO, to revoke a patent. I do not believe that Section 77 has that meaning. Subsection l brings a European patent within those sections of the Act which relate generally to patents. Thus there attach to European patents (UK) the same rights as attach to national patents and they are treated in the same way in this country. Subsection (2) enables the provisions of the Convention, relating to amendment and revocation, also to operate. The fact that there may be proceedings both in the National courts and before the EPO is inevitable as patent rights, both under the Convention and under the Act, are national rights to be enforced by the National courts with revocation and amendment being possible in both the National courts and in certain circumstances before the EPO. That overlap can mean that there are parallel proceedings in this country and the EPO with the potential for conflict. It is desirable for that to be avoided. Therefore the Patents Court will stay the English proceedings pending a final resolution of the European proceedings, if they can be resolved quickly and a stay will not inflict injustice on a party or be against the public interest. Unfortunately that is not always possible as resolution of opposition proceedings in the EPO takes from about 4 - 8 years.

Section 77(2) cannot have been meant to remove the right of the English courts under Section 72 to revoke invalid patents pending expiry of the opposition period and resolution of opposition proceedings which could last up to eight years. If patents are invalid, then the National courts have the power to revoke them at any time after grant. That causes no injustice. A patentee has ample opportunity to amend his patent in this country and it is right that he should bring before the Court all the issues which need to be determined. If he wishes to seek amendment, he should formulate his amendment at the earliest possible time so that the court can determine validity and infringement with the proposed amendment in mind. Section 77(2) preserves the operation of the Convention but does not curtail the jurisdiction of the Patents Court to revoke an invalid patent.

I conclude that both patents are invalid. I would dismiss this appeal.

I agree.

I also agree.

Order: That the Notice of Appeal be amended in the form annexed to the summons dated 8th January 1997; that the appeal be dismissed and that the order of Mr. Justice Jacob dated 14th July 1995 be affirmed; payment of costs on undertaking to repay; leave to appeal to the House of Lords refused; that the order for revocation of European Patents (UK) No. 0334 899 and 0345 266 contained in the order of Mr. Justice Jacob dated 14th July 1995 be stayed for a further 21 days so that if within the period of 21 days the plaintiffs' petition for leave to appeal to the House of Lords against this order the order for revocation be further stayed until the petition be refused or, if granted, until judgment, provided that any such petition, appeal or application be prosecuted with due diligence.