Case No: HC 00 5233
Neutral Citation Number: [2002] EWHC 8 (Patents)

IN THE HIGH COURT OF JUSTICE
CHANCERY DIVISION
PATENTS COURT
Royal Courts of Justice
Strand, London, WC2A 2LL

Date: 24 January 2002
B e f o r e :

THE HONOURABLE MR JUSTICE JACOB
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	(1)  Steven Tickner
(2)  Timothy Woodhouse		Claimants	
	-	And   -		
	(1)  Honda Motor Company Limited (a company 
incorporated under the laws of Japan)
(2)  Honda Europe NV (a company incorporated under the laws of Belgium)
(3)  Honda Motor Europe Limited	Defendants	
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Anthony Watson QC and Geoffrey Pritchard (instructed by 
Memery Crystal for the Claimants)

Peter Prescott QC and John Hornby of Clifford Chance for the Defendants

HEARING DATE:  13/14/15 DECEMBER 2001

I direct that pursuant to CPR PD 39A para 6.1 no official shorthand note shall
be taken of this judgment and that copies of this version as handed
down may be treated as authentic

THE HON MR JUSTICE JACOB
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A copy of this judgment will be available on the court service website www.courtservice.gov.uk

Jacob J

1.	This is an action for infringement of UK patent No. 2,303,004. Amendment of the patent is sought and opposed.  Validity is attacked, but only if it is held that the claims cover the alleged infringement.

General Background

2.	Two individuals, Messrs. Tickner and Woodhouse, own the patent.   Mr Woodhouse was the inventor and sole original applicant for the patent, the application being filed on 6th November 1996 with an unchallenged priority date of 9th November 1995.  Mr Tickner agreed to finance the costs associated with the patent and as part of that agreement became a joint proprietor in March 1999. This litigation is funded by insurance.

3.	The defendants are well-known manufacturers and designers of motor vehicles and engines.  Their engines range from the large to the small.   This case is concerned only with one type of Honda engine - a low power single cylinder overhead camshaft engine going by the designation "GC".    They are for tillers, generators and the like.  There are the GC135 and the GC160, the latter being slightly larger than the former, nothing turning on the difference.   Originally two other GC engines were said to infringe.  These had vertical crankshafts and were used for lawnmowers.   Owing to certain prior art the patentees seek amendments to claim 1 which take these engines outside its scope.    They also seek other amendments.
 
The witnesses

4.	Each side called an expert, the claimants Professor Sheldon and the Defendants Mr Neale.   Professor Sheldon is the Emeritus Professor in Design and Engineering at Anglia University having been the Ford Professor in Automotive Systems.   He is the principal figure in a firm of Consultant Engineers.  He has much experience as an expert witness over 25 years.  Mr Prescott QC cross-examined him over that experience - it ranged over a wide variety of fields.   The purpose of the cross-examination was to show that the Professor had spread himself thinly and could not be a proper expert in relation to the many fields in which he claimed expertise.   There is some force in this: certainly he had never actually designed an internal combustion engine or been a member of a design team which had done so.  On the other hand the technology with which this case is concerned is not at a level where detailed knowledge of such work is required.  So I do not regard the criticism as going far enough.  Professor Sheldon was qualified enough at the level of generality called for in this case, though his knowledge of tribology was weak.

5.	More serious, however, was Mr Prescott's other principal attack.   Professor Sheldon was alleged to lack impartiality.   For instance his first written report failed to mention that oil pumps were not used in small engines (see below).   That was surely relevant given that the patent in suit asserted that pumps were traditionally used and made no reference to pumpless engines.  The problem of lack of objectivity became much more evident, however, when Mr Prescott came to cross-examine him about the specific embodiments of the patent in suit. He gave some astonishing answers.  He refused to accept that these embodiments were only of a pressure lubrication system.  He refused to accept that it was almost certainly a 4-cylinder engine which was being described.  He refused to accept that the kind of motor concerned was for a motor vehicle.  But all that is obviously so on any fair reading of the patent.   It is not strenuously denied.   The details of all this are set forth in Mr Prescott's closing Skeleton.  I agree with what is there submitted.   I am afraid that I cannot place any weight on any of Professor Sheldon's evidence.  Mr Prescott rightly elected not to proceed further with his cross-examination:  there is no point in debating matters further with an expert witness who is not prepared to accept that which is both obvious and basic.

6.	Mr Watson QC for the defendants suggests otherwise - indeed goes so far as submit that Professor Sheldon's un-crossexamined evidence should be taken to stand.  I reject that.  Once it has been shown that an expert's evidence upon an important matter is clearly and obviously untenable it is legitimate for the tribunal to conclude that his opinions are tainted and to disregard his evidence.  The cross-examiner can stop.  Whether he does so nor not, the judge can drop his pen.

7.	I turn to Honda's witnesses.  They were Mr Neale, a past-President of the Institution of Mechanical Engineers and Mr Shimizu, Honda's Chief Engineer.   Mr Neale is a world-class expert on tribology but also has immense practical experience having come up through the shop-floor of Rolls-Royce and then Glacier Metal.  He is the editor of the Tribology Handbook which gives guidance on the choice of lubrication for all sorts of machines.   Mr Shimizu gave evidence as to the details of the development of the GC engines.    Mr Watson accepted that both witnesses were genuinely trying to assist the court.  I so found.  Mr Shimizu had the particular difficulty that he was giving evidence through an interpreter, excellent though that interpreter was.  But even so his answers were clear, careful, direct and frank.

8.	In the end Mr Watson submitted that he could base his case solely on the evidence of the Honda witnesses.   To that I will come, but for present purposes it is sufficient to say that I pay no further attention to Professor Sheldon's evidence.

9.	Finally, on the witnesses, there were a number of unchallenged witness statements.  They went, so far as the defendants' were concerned, to prove two prior uses: one in the 1970's of a Honda motor called the P25 and the other in the 1990's of a Fichtel & Sachs motor called the SB180.  In the end the prior uses were admitted.  Neither were shown to be generally known to engine designers.   On the claimant's side, both patentees gave evidence about their knowledge of the prior art, a point which could have affected the court's discretion to allow amendment.  No challenge to the amendment is made on that ground.
  
Technical Background

10.	This case is concerned with the lubrication systems for 4-stroke engines.  These operate by a series of 4 strokes (induction, compression, power stroke, and exhaust).   Several varieties of such engines were well known.  Mr Neale described the position thus:

"All engines require a valve or port system to admit and exhaust the working gases from the cylinder and various valve arrangements are shown in Figure 1. Earlier engines had these valves at the side of the cylinder head and opening in an upward direction into a sideways extension of the cylinder head combustion chamber. The camshaft, which operated these valves, was therefore positioned at the side of the engine, adjacent to the crankcase, and therefore with the potential for splash lubrication from the crankshaft, as described in paragraphs 17 and 21. Modern engines have a more compact hemispherical combustion chamber to give greater efficiency, reduced emissions, and with the valves mounted on the top of the cylinder head and opening in a downwards direction. Such overhead valves can be operated by rods and rocker levers from a camshaft in the original position, but modern designs tend to use a simplified operating arrangement, with the camshaft mounted above the cylinder head to operate the overhead valves more directly."

Mr Neale's figure 1 is as follows:

11.	Of course modern motor cars have highly rated engines and use multiple cylinders.   Lawn-mowers and the like have much lower power ratings.  They are single cylinder.  Commercially they are also designed for surprisingly short operating lives - a few hundred hours. That will be enough for several years' use.  By way of contrast a motor car engine will be designed for several thousand hours use.

12.	The component which receives the hardest use in either kind of engine is the "big-end", a plain bearing used to join the crankshaft with the rod which connects it to the piston.   The big-end transmits the thrust from piston to the crankshaft to drive the engine.   The thrust is high, but lasts only a short time.  So, when it is applied, there is not enough time for the oil in the bearing to be squeezed out from the clearance space between the crankshaft and the bearing.   Of course it is necessary that this space be reasonably filled with oil before the load is applied.   In low power engines (for instance lawn-mower engines), or indeed in early motor car engines, the big end could be lubricated simply by oil splash.  Mr Neale put it this way:

"many lower rated engines, and certainly those in lawn mowers, do not require an oil pump supplying oil under pressure to provide satisfactory service lives, because the oil splash generated by the moving components, provides a sufficient oil feed rate for adequate lubrication of the working parts, including the crankshaft bearings and the cylinder head area. This oil splash is typically generated by arranging for some of the moving components to have limited contact with the oil in the sump. The contact has to be limited because otherwise various components such as the pistons and rings would be flooded with oil and be unable to prevent excessive amounts of the oil from reaching the combustion chamber."

This is not true for higher rated engines, such as those used in motor cars.   For these you need an oil pump - mere splashing will not be enough.  Mr Neale explained why:

 "The  engine may be running at 3,000 RPM, it will be firing 1500 times a minute, that is 25 times a second.  You would therefore have a very rapid fluctuating high load being applied 25 times a second to the shaft.  The way in which that is carried is not so much by this relatively simple mechanism but another one, which is known as a squeeze film which is that it takes a certain amount of time for the oil to be squeezed out under a high load.  Therefore, for these very short periods of time such as occur on an engine crankshaft you can get a very high load capacity because of the effect of the time it takes to squeeze out the oil. But the important point is that, for that to be effective 25 times a second, it is essential before the load is applied the next time that that oil film is fully filled with oil.  Now, that is the reason why we require a pressure supply on more highly rated engines: it is to fill that space to be ready to carry the high load that will occur each time the engine fires."

Mr Neale caused to be conducted an examination of a number of small 4-stroke engines on the market just before the priority date.  It showed that none of them below 6kW in power used pressure lubrication - all lubrication was by splash from a sump promoted by moving components.  20 of these engines had side valves; the remainder were overhead valve engines.  None, however, were overhead camshaft engines.

13.	I must say a little more about overhead camshaft engines.   They were (and are) recognised as more efficient than side valved or overhead valve engines whose valves are operated by rods and rockers.  This did not matter for small engines until shortly before the patent when regulations about emission and efficiency affecting these started to come in, in about 1994. It was these which spurred Honda to embark on designing the engines which were to become the GC engines.  They were also the spur to the development of one of the cited pieces or prior art, the Fichtel and Sachs SB180 engine.

14.	I should also mention a few other well-known matters concerning OHC engines.   You can have the crankshaft horizontal or vertical. For a vertical crankshaft engine the cylinder is horizontal.  The terminology "overhead" continues to be used for these engines - it means the camshaft is in a cylinder head end remote from the crankshaft rather than physically above the crankshaft.   A vertical crankshaft engine is suitable where a vertical drive is required, for instance in a rotary mower.  A horizontal crankshaft is suitable for a horizontal drive, such as is used in a cylinder mower.   

15.	Next there is the question of how a camshaft is driven.   Self-evidently it is of critical importance that it operates synchronously with the crankshaft: valves must open and shut at the right times.   In the case of side valve and overhead valve systems (the left and central examples in fig.1) the camshaft is sufficiently close to the crankshaft that it can be driven by direct gearing.   But where an overhead camshaft is used, it must be connected by a chain or toothed belt running over toothed pulleys.  Such a device is called a "timing" chain or belt because it must maintain synchronism.  Both timing chains and timing belts were well-known at the date of the patent, but in the case of belts, only when used externally, that is to say outside the crankcase.   It was recognised that belts had advantages, particularly in relation to noise.  For that reason they were well-known in motor car engines.  However, until the Honda GC engines, a timing belt had never been used inside the crankcase. To be commercially viable, any such belt would have to be able to withstand the environment (heat and oil) within the crankcase.   On the evidence no suitable material was publicly available at the date of the patent, though Honda had access to a special, private, source which had been developed in conjunction with them by another company in the late 1980s.

The Teaching of the Patent

16.	The patent begins with the following two paragraphs:

"This invention relates to lubrication systems for internal combustion engines.  Such engines have been established for over 100 years, and there has been no fundamental change to their lubrication system over the years.  Thus, it is traditional to provide an oil lubrication system in which a separate oil pump is provided for circulating the oil to the various moving parts thereof.

An object of the invention is to provide a lubrication system in which oil is circulated without the need for a separate pump."

17.	The second sentence of the first paragraph is not accurate so far as small (less than 6kW) engines are concerned.   Indeed it is wholly wrong.  None of them had separate oil pumps.   All relied upon splash.   So the second paragraph, setting out the object of a lubrication system which does not have a separate pump, is inapplicable to small motors.  The patent then goes on to state the invention in the same language as that of the unamended claim 1:

"According to the invention, in an internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting these shafts via respective pulleys, the timing belt is adapted at all times when the engine is in operation to entrain a sufficient quantity of oil from the oil sump to lift it to the cylinder head for lubricating purposes."

I return to the meaning of this when I come to claim 1.    The patent goes on:

"Conveniently, oil is returned to the sump via an oil cooler, to enable the entrained oil to be used additionally for cooling purposes."

The use of oil coolers is not applicable to small engines but is well-known in motor car engines - another indication that the concern of the patent is not small motors.

18.	There follows an uncontroversial statement of well-known fact:

"As known per se, the camshaft and crankshaft pulleys have similarly formed tooth sets, but are of different diameters to effect the timing required, and the timing belt is of an impermeable material over its width and formed with a set of teeth around its inner face for meshing with said toothed pulleys."

That is, of course true in all OHC engines which use a timing belt.    The same goes for a chain.   The patent then goes on to the patentee's special idea of an additional "oil pulley" which meshes with a special extra set of teeth on the other side of the timing belt:

"In accordance with a feature of the invention, an additional oil pulley is provided immersed in oil within the oil sump, and below the level of the crankshaft pulley, the oil pulley also being toothed and the timing belt having an additional set of teeth extending around its outer face for meshing with the teeth of the oil pulley, said outer teeth providing the means for entraining oil to the cylinder head.

In one form, the additional set of teeth may be formed with scoops for entraining the oil.

Preferably, said additional teeth are designed to run closely within a closed passage, whereby they act with the wall of said passage to entrap and entrain said oil.

Preferably the engine lubrication system includes a toothed pulley, the teeth of which run over a part of the rotation within a restricted passage and a belt having matching teeth which also runs for part of its movement within a restricted passage, these runs being guided to a meshing point at which oil under pressure as a result of the meshing action is available."

19.	The patent then goes on to describe two embodiments, one by reference to figures 1-4 and the other by reference to figures 5-6.   I do not think it necessary to include these within this judgment.  It is enough to state the general idea because it not in dispute.  It is to use a timing belt which has teeth on both sides, in combination with a "pulley wheel" to operate as an oil pump.   The toothed wheel is partially immersed in the sump.  The wheel has circumferentially disposed "open-ended pick-up ports."   As the wheel turns oil enters these.  It can exit at the edge of the wheel via "radial transfer ports".  The upper side of the wheel meshes with the pulley fixed to the crankshaft and the timing belt.  The patent describes what happens as follows:

"Consequently, the oil is then forced through the ports 22 by its own inertia and a squashing action of the toothed timing belt engaging with the oil pulley.  Oil from the oil pulley pick-up ports 17 flows out of the transfer ports 18 effectively formed between the oil pulley teeth 8, before and after meshing with the teeth 9 of the timing belt.  Consequently, the outside run of this belt is filled not only with oil from the ports 22, but also by centrifugal force acting on the oil as a result of the meshing action with the oil pulley.  When oil has been transferred to the outside run of the belt, it is thus forcibly lifted through the closed passage 16 to the outlet 13 in the cylinder head 15.  At this point, oil under pressure is then directed, as required, through the oil gallery 14 for the purpose of lubrication and, in the case where an oil cooler is included in the system, also for cooling.  When the cooling and lubrication functions are complete, oil is returned to the sump 3 via the branches 14A, 14C and 14D."

20.	I have underlined the portions which indicate that the patentee envisages his device generating an oil pressure. The kind of engine shown is obviously a 4-cylinder machine.  It has what is described as an "oil gallery" in the cylinder head area.    The timing belt acting in combination with the other components generates an oil pressure at the upper outlet in the cylinder head, which is described as follows:

"Referring to Figure 4, and also to Figure 1, the cylinder head 15 is provided with an oil gallery 14 which is fed from the outlet 13 of the casing 10.  The gallery includes a branch 14A for feed to the crankshaft big end, branches 14B for the cylinders and return via the branch 14A to the big end, branch 14C for ancillary equipment such as the engine valves and associated tappets, and a branch 14D for overflow back to the oil sump 3."

One takes it that there are 4 cylinder because there are 4 branches 14B.  And, of course, the word used is "cylinders" in the plural.

21.	Thus the oil under pressure is directed to lubricate not merely the camshaft, but also, via a pipe to the crankshaft.   No figure for the oil pressure is given for the first specific embodiment of the invention.  For the second embodiment (a variant of the meshing system) a figure on the oil pressure achievable is actually given, namely 30 psi.
22.	The patentee concludes by setting out the advantages of his invention.  I have underlined the important bits about pressure and lubrication of the big-end.

"It will be appreciated that the system and modification described above have the following advantages:

	1.	drives and times the camshaft.

	2.	pumps oil to the cylinder head.

	3.	delivers oil to the big end bearing.

	4.	delivers oil to the main bearings.

	5.	delivers oil to the camshaft.

	6.	delivers oil to the camshaft bearings.

	7.	delivers oil through oil galleries and cooling ducts.

	8.	delivers oil if required to the gearbox.
9.	the oil takes heat from the cylinder head and/or cylinder and returns it to the 25 sump by way of various components that are lubricated on the oil’s return.

10.	acts as an oil pump and a coolant pump.

11.	the oil effectively damps out mechanical noise to a very large extent, the integrated cam drive, lubrication and cooling system effectively formed being extremely quiet in operation.

12.	significant gains in torque, acceleration and horse power; significant reductions in noise, cost and lost power with full lubrication of vulnerable parts on cold start up."

23.	There is no doubt whatsoever that the specific embodiments teach a device which acts as an oil pump. Hence my astonishment at Professor Sheldon's evidence.   The described mechanism is clearly intended to provide all the lubrication the system needs, and in particular not only that for the cams and camshaft.  Mr Prescott submits, rightly, the embodiments of the invention do not dispense with a pump.  What the patentee has done is to invent a different sort of pump.  He has done away with the need for a separate pump by ingeniously using a combination of a special timing belt, oil pulley, meshing mechanism and closed passage.   It is these which bring the oil, under pressure, to the cylinder head.   

24.	Putting the matter another way, what the patentee has not taught or disclosed is a different concept - that which Mr Prescott called "wet the drive" camshaft lubrication.   A better phrase might be "splash the drive".   It means a combination which provides lubrication of the cams and camshaft by simply incorporating the timing belt (or chain) within the engine so that the general splash which lubricates the other parts (big and little ends) also fell on the belt or chain.  It would then carry oil up to the overhead cams and camshaft.   Such a system is unpressurised.  And it only provides lubrication of the cams and camshaft.   It depends merely on the oil just "sticking" to the belt by virtue of its viscosity.   It would likewise stick to a chain.

25.	Mr Watson submitted that some of the general language at the beginning of the patent indicated that more was taught than the special combinations described specifically.  But I think he was grabbing at straws with hindsight.   He relied upon three matters:
 
(1)    The reference to the "additional set of teeth being formed with scoops for entraining the oil".    But that is in no way inconsistent with the patentee's concept of a specially designed arrangement whereby the timing belt lifted oil up under pressure so that the whole system could be lubricated;

(2)    The statement that the "additional teeth are designed to run closely within a closed passage, whereby they act with the wall of said passage to entrap and entrain said oil" begins with the word "preferably."   From that word alone, says Mr Watson, the skilled man would infer that it was not necessary to have a closed passage and hence "wet the drive" is taught.   But it is also Mr Watson's case that "wet the drive" is non-obvious.   I cannot imagine that the single word "preferably" would teach what is said to be a non-obvious invention.   And as Mr Prescott pointed out there maybe other ways of delivering oil under pressure which did not use a closed passage or extra teeth - he postulated bucket shaped teeth on one side of the belt.  These would lift oil to near the camshaft pulley where some device squashed the oil out so that it was under pressure.  In effect that would be moving the squashing action of the specific embodiments from the crankshaft pulley up to the camshaft pulley - it would be consistent with the inventor's concept of doing away with a separate pump by using a special mechanism involving the timer belt to develop some pressure.

(3)   The third point again rests on the single word "preferably, which opens the next paragraph (which I have quoted above).   What have said about point 2 applies to this with equal force.

Claim 1   

26.	The key issue of construction applies to the proposed amended claim in exactly the same way as it applies to the unamended claim.   The claim as sought to be amended reads as follows:

An internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting the crankshaft and camshaft via respective pulleys, wherein the timing belt is adapted at all times when the engine is in operation to entertain entrain a sufficient quantity of oil from the oil sump to lift it to the cylinder head for lubricating purposes wherein the axis of rotation of the crankshaft is horizontal and wherein the axis of rotation of the camshaft is located in the same vertical plane as the axis of rotation of the crankshaft.

27.	In the end there was no dispute over amendment of this claim.   Correction of the obvious misprint is trivial.  The proposed limitation to "at all times when the engine is in operation" was dropped after I indicated that I thought it unallowable as adding matter but that dropping it would not be so material a matter as to require advertisement.  The limitation at the end of the claim - effectively to a horizontal crankshaft engine was not opposed.

28.	So I turn to construction.  There is no dispute as to principles.   The basic rule is that the monopoly is determined by the terms of the claims and that the description and drawings shall be used to interpret these, EPC Art. 69.   The Protocol on the Interpretation of Art 69 directs the court to eschew on the one hand a strict literal meaning out of context or on the other a mere guideline approach.  A position between the two extremes, combing fair protection for the patentee with a reasonable degree of certainty for others is called for.  The Courts of England and Wales have developed a series of well-known questions (the so-called Protocol questions) to assist in the inquiry:  these are a "useful tool to arrive at the middle ground" per Aldous LJ in Pharmacia Corpn. v  Merck, 14th December 2001 [2001] EWCA Civ 1610.  No-one suggests they are, or could be, the be-all and end-all of the matter.    The whole approach goes by the sobriquet "purposive construction".  You learn the inventor's purpose by understanding his technical contribution from the specification and drawings.  You keep that purpose in mind when considering what the terms of the claim mean.  You chose a meaning consistent with that purpose - even if that involves a meaning which, acontextually, you would not ascribe to the word or phrase.     Of course in this exercise you must also be fair to the patentee - and in particular must not take too narrow a view of his purpose - it is the widest purpose consistent with his teaching which should be used for purposive construction.
 
29.	I turn to the disputed words in this case.   First for lubricating purposes.   Mr Prescott submits that the inventor's purpose is to lift oil to the head for lubricating not merely the cams and camshaft, but the whole engine - what is claimed is essentially a total lubrication system.   That is the only purpose indicated in the specification.  Thus the lubricating purposes of the claim mean the lubrication of various moving parts of the engine - the parts hitherto lubricated by a separate oil pump.

30.	Mr Watson submits that it is sufficient if the cams and camshaft are lubricated.    He submits that the Prescott construction means adding words to the claim which simply are not there, words such as wherein the oil lubricates the engine generally.   Moreover, he submits, the Prescott construction will not do, because it is self-evident, even in the case of the specific embodiments, that there will be a certain amount of splash lubrication.   The patentee cannot have intended to exclude these embodiments.   Finally, submits Mr Watson, what about the subsidiary claims?  It is only in unamended claim 7 that pressure is mentioned (and then only in association with the specific meshing action which produces it).  So, by inference, the earlier claims are not limited to pressurised lubrication.   

31.	I conclude that Mr Prescott is right.   He is right essentially because, giving the claim a purposive construction, mere splash the belt solely for the purpose of lubricating the cam and camshaft was not within any purpose contemplated by the inventor.   Now it is of course trite law that within the scope of a patent claim there may be inventions never conceived by the inventor.  All improvement patents are of that sort.  But later improvements build on the earlier conception of the inventor. That is not the case here.  Wet the belt is not an improvement of the inventor's concept. It is an essentially different concept.  It needs a different (and much simpler) kind of mechanism to achieve it - nothing more than an internal belt near a splasher.   Actually a chain would do as well as a belt. A chain will equally serve just to pick up oil and carry it upwards.  The inventor, on the other hand, needs a belt because a chain could not deliver oil for his purpose.

32.	Mr Prescott finds reinforcement, in my opinion, from the words wherein the timing belt is adapted to entrain.   This conveys the notion that it is there is something special about the belt itself - as indeed there is in the case of the patentee's specific embodiments.   One would hardly describe a perfectly ordinary timing belt as adapted to entrain.   Yet if the claim covered the splash the belt concept, one would have to give the expression an ambit wide enough to include a perfectly ordinarily shaped belt which is simply positioned to catch splashed oil.  I do not say the words could not have had that meaning if they had accorded with the inventor's purpose, but, as I have said, there is no such purpose disclosed.

33.	I turn to Mr Watson's points.  First I do not think that Mr Prescott's construction really involves adding words to the claim.  The claim itself says lubricating purposes, which invites the inquiry, what purposes?  Or putting it another way, Mr Watson's construction also requires the addition of at least a word - he would say it means any lubricating purpose.    More fundamentally his approach is literalist - it avoids using the specification and drawings to interpret the claim.    And it gives more than fair protection to the patentee, covering something he never envisaged either specifically or generally.   It also does not give third parties reasonable certainty - catching them even though what they do owes nothing  to the inventor's conception in its widest form.

34.	Next there is Mr Watson's point that even the specific embodiments will involve some splash lubrication.  That is so - indeed for the specific embodiment the patent specifically envisages that at start-up the big end bearing is lubricated by splash "for the short time it takes for oil pumped via the timing belt 5, to reach it.."   But that it is not the point.   The engine of the patent does not depend on splash lubrication.   It relies on total lubrication via oil pumped by the timing belt.   

35.	Finally there is the construction by inference point - that pressure is only mentioned in claim 7.   This is the hoary old "claim 1 - a motor car;  claim 2 - a motor car wherein the wheels are round" sort of argument.  It is essentially linguistic rather than purposive.  Indeed it bears a close comparison with the unsuccessful "meticulous verbal analysis" of the Catnic case [1982] RPC 183 at p.243.  There the patentee had used the phrase "substantially parallel" for the horizontal plates of the lintel but the unqualified word "extending vertically" for the rear support member.  The losing argument was that the patentee had indicated substantiality when he wanted to, so, by inference, when he used "vertically" he meant true vertical and nothing else.

36.	I asked Mr Prescott whether he contended that it was inherent in claim 1 that there was some pressure developed.  He could not give a yes or no answer - and I think he was right to do so.  The point is this:  it is well settled that a patentee need not disclose or claim only that which will be commercially practicable.   It is enough that he discloses a device which will work to some extent.  Now when one comes to lubrication of engines no-one expects lubrication to extend their life indefinitely.  On the other hand even without lubrication, or commercially adequate lubrication, they will work to some extent before seizing up.   So even if oil is not delivered under pressure to the big end of a motor car engine, the engine will run for a bit, particularly if not under extreme conditions.  So the patentee's engine could work even if the oil is not delivered under pressure to the big-end.   On this analysis the claim is not inherently limited to delivery of oil under enough pressure to lubricate the big-end properly for a practical commercial engine.  Even so, it appears to me that the claim does require that there is pressure enough to deliver some oil to the big-end for lubricating it significantly.  In the case of the specific embodiments that means enough pressure at the head to force oil through the oil-way for delivery to the various moving parts and of course particularly the big-end.   I say "particularly" for two reasons:  first the skilled-man would regard that as the most important part and secondly because is remote from the engine head and thus will require some pressure at the head to force the oil through a comparatively lengthy oilway.   Of course what the patentee principally conceived was enough pressure to do the same job as was previously done by a separate oil-pump. I do not think the claim is limited to such a high pressure - but it is limited to a system which provides enough pressure to deliver oil to the entire system and particularly the big-end.  

Infringement

37.	In the end there was no dispute as to the technical facts.   The Honda GC engine have two members which cause oil splash.  There is a dipper at the end of the connecting rod.  This dips in and out of the sump producing some splash.   But most of the splash is caused by a pair of blades on a specially driven wheel which is partially within the sump.  The splash lubricates both big and little ends.   The splash also hits the internal timing belt.  There is nothing special about the shape of this belt.  It is not "adapted" in any way to carry oil.  Oil just sticks to it and is carried up to the head.  The claimants' video shows that there is a veritable torrent carried up.  It is flung off at the top.   Thus the head, cams and camshaft are lubricated.   As a technical matter I am satisfied, however, that much more oil than is needed is supplied.   Mr Neale, whose evidence I accept, was of this opinion, basing himself on an experiment conducted with the belt disconnected.    Professor Sheldon seemed prepared to accept this, but opined that more oil was needed for washing away any particulate matter.  Mr Neale and Mr Shimizu, whose views I prefer, both disagreed - pointing out that any such washing would be done with "dirty" oil and so pointless.   

38.	Thus in the GC engine the fact that a mass of oil is delivered to the head by the belt does not mean that that mass is essential for lubrication.  However it does provide lubrication at the head, swamping any effect which the splash below might otherwise achieve on its own.   The remainder of the engine is lubricated simply by splash from the sump. Accordingly I do not think the engine falls within claim 1 as I have construed it.   There is no lift of [oil] to the cylinder head for lubricating purposes.   And the timing belt is not adapted to entrain oil.

Validity - General

39.	On the basis of the construction which I have reached Mr Prescott does not attack the validity of claim 1 as proposed to be amended.  Only if the claim encompasses "wet the drive" or "splash the belt" does he do so.   I therefore proceed to consider validity upon the supposition that I am wrong on construction and the claim encompasses "splash the belt."

Validity - Insufficiency

40.	Mr Prescott's first point is another prong of his construction point.   Since it was primarily an argument on construction I allowed, without objection from Mr Watson, a late amendment to make the point explicit.  The amendment reads as follows:
“The claimants are asserting that the patent covers an engine which uses the principle of employing a rotary device for splashing oil out of the crankcase sump to wet a camshaft timing belt having teeth on one of its surfaces, so that oil is flung off the belt in order to lubricate the camshaft.  This is denied.  If, however, the patent does cover an engine which uses the aforesaid principle, the patent does not teach that principle.  Rather, the only principle of lubrication taught by the patent is to employ a timing belt which moves closely within a restricted passageway.  Alternatively (which is not admitted) the patent teaches the principle of not having a restricted passageway but using a timing belt which is provided with teeth on both of its surfaces, oil being supplied to the belt by a so-called oil pulley.  Accordingly, the scope of the monopoly asserted by the patentees does not correspond to the technical contribution made by the patent”.

41.	This is so-called Biogen insufficiency.   Mr Prescott relies upon the speech of Lord Hoffmann in Biogen v Medeva [1997].  He says the claim would cover "ways which owe nothing to the teaching of the patent or any principle which it disclosed."   I think he is right.  If the claim covers "splash the belt" and that concept is, as Mr Watson contends, non-obvious, then the patent does not teach it.   So, to that extent, "the specification of the patent does not disclose the invention clearly enough and completely enough for it to be performed by a person skilled in the art" (s.72(1)(b) of the Patents Act 1977). 

42.	Mr Watson submitted that this will not do - that this is really an objection that the claims have no fair basis in the specification.  Such an objection is no longer a ground of invalidity.  He relied upon what was said by Aldous LJ in Auchinloss v Agricultural & Veterinary Supplies [1999] RPC 397 at p. 402:

"There is nothing in the claim requiring that the generated hypohalite ions should be materially or substantially responsible for the biocidal action of the composition.  To introduce such a requirement, as the judge did, is impermissible.  In effect it is introducing, by way of construction, a requirement that the claim must be fairly based on the patent specification which was a requirement under the Patents Act 1949, but is not under the Patents Act 1977."

43.	However Aldous LJ was not considering an allegation of Biogen-type insuffiency.   He was merely considering a question of construction of the claim in that case.   I agree that one cannot under our present law attack a claim simply on the ground of "lack of fair basis".  But that old ground of attack overlapped with others - utility, false suggestion, insufficiency and even obviousness could each cover part of the same ground as lack of fair basis in the pre-EPC days.  The last two grounds continue to apply.   So it is not an objection to an insufficiency attack to say that it could have been an attack of lack of fair basis in the past.  You just ask the statutory question under s.77(1)(b).   Whether it overlaps with the "fair basis" attack of the past is neither here nor there.

Obviousness

44.	Again this ground is only raised if the claim covers the splash the belt concept.   	Was then, the concept obvious?   To decide this question it is necessary first to determine the background knowledge of the skilled man - the "common general knowledge." There was no real dispute as to this.  I have set out most of it above under the heading Technical Background.   The experts had a meeting and set out matters on which they agreed and disagreed.  The document would have been more helpful if they had specifically addressed the items of agreed common general knowledge separately.  In future patent actions this would normally be a desirable course.

45.	 The following further matters were agreed to be well known. I have in some cases added a little more detail established by the evidence

1.   Small side and overhead valve engines without an oil pump and relying on splash lubrication alone; 

2.  Oil splashers for such engines;

3.  Big-end lubrication under pressure is needed for highly rated engines but not for low-rated engines for which splash will do.

46.	What were not established as common general knowledge were any of the specifically cited pieces of prior art.   Plainly none of them were well-known.   Indeed the P25 Honda engine was not even known to Mr Shimizu, the designer of the GC engines.   Only after he had designed the engine was he told by his supervisor that his design was similar to that of the P25.

47.	Since each piece of prior art is not shown to be common general knowledge, each must be approached individually.   The unimaginative skilled man, having all the relevant common general knowledge is assumed to read (or in the case of the prior uses), examine, all the art.    He may "mosaic" two pieces of prior art but only to the extent that it is obvious to do so.  As Lord Reid put it in Technograph Printed Circuits v Mills & Rockley [1972] RPC  346 at p. 355 "it must be a mosaic which can be put together by an unimaginative man with no inventive capacity."

48.	In this case, curiously, it is not the defendants but the patentees who seek to make a "mosaic" of priority documents.   The most dangerous of these is Japanese UM 60-159610 published on 24th October 1985 ("Fuji 1").   Its effect is lessened if it can be read with Japanese UM 60-209616 ("Fuji 2").   Mr Neale agreed that if he were researching the literature he would want to read the two together - particularly as they were filed on the same day.  There is nothing imaginative about that.  So I see no reason why the skilled man might not make such a "mosaic".

49.	With these preliminaries I can turn to the well-known Windsurfer questions.   

Step 1 - the inventive concept

I assume here that it is "splash the belt" to lubricate the head in a horizontal crankshaft OHC engine.    This involves, of course, putting the belt within the engine casing.

Step 2 - the common general knowledge

This I have identified already
Step 3  - identify the differences between the cited prior art and the inventive concept
This must be done for each piece of prior art which is not common general knowledge.
Step 4	- are the differences obvious or did they require any degree of invention?
Again this must be done separately for each piece of prior art.
Fuji I and 2
50.	I turn to steps 3 and 4 for the items of prior art relied upon, beginning with what Mr Prescott said was his most powerful item, Fuji 1.    This describes a single cylinder OHC engine "in which a lubrication performance of the chain is improved."   The patent says:
"Generally in an OHC engine, an oil pump or the like is used to lubricate a principal bearing portion, a sliding portion or the like.  However, particularly in an OHC engine having a single cylinder, since installation of a forced lubrication apparatus such as an oil pump costs much and is not economical, a so-called scrape splash type lubrication system is conceived, in which an oil scraper is provided on a revolutionary portion such as a crankshaft, and lubrication oil in an oil pan is splashed, thus the lubrication oil is supplied to each bearing portion or each sliding portion.
However, in this scrape-splash type lubrication system, since the lubrication oil is splashed with the oil scraper, there may be a case where the splash tends not to be even and the oil is not supplied sufficiently to a place on which the lubrication is necessary.  Particularly, it is necessary to supply sufficiently the lubrication oil on a sprocket portion or a chain portion in an OHC engine with a chain drive."
"… the object of the present device is to provide an OHC engine lubrication apparatus, which catches an oil mist scraped and splashed with an oil scraper to supply the oil mist to a sprocket portion or a chain portion and can improve a lubrication performance of the sprocket, the chain and the like with a simple structure without installing a forced lubrication apparatus such as an oil pump.
In order to achieve the foregoing object, the OHC engine lubrication apparatus of the present device in an OHC engine with a chain drive, which has a structure in which an oil scraper is fitted onto a revolutionary portion within a crankcase to scrape and splash lubrication oil in an oil pan within the crankcase, is constituted such that a guide portion is provided, which is formed on an upper portion of a sprocket or a chain within the crankcase to catch an oil mist and to flow down or drop down the oil mist on the sprocket or the chain."
51.	Fuji 1 says nothing explicitly about lubrication of the cams and camshaft. Its explicit purpose is lubrication of the chain itself - a job which is not necessary in the case of a belt because the latter has no links.   The defendants' case is that it is necessarily implicit that lubrication of the head by oil flung off from the chain is taught.   On that basis the only difference between Fuji 1 and the concept of claim 1 is the use of a belt rather than a chain.   
52.	I am not convinced by this.  Fuji 1 is aimed at lubricating a chain.     True it is internal to the crankcase.  The inventors seem to have thought there was a problem in getting lubrication or enough lubrication to the chain itself.  Chains, unlike belts, themselves need lubrication. Fuji intend to do away with a "forced lubrication apparatus such as an oil pump" but have not thought the thing through.  They simply did not address the question of head lubrication.   Moreover even if the skilled man could read head lubrication by a chain into Fuji 1, it is not self-evident that he would then see a belt as a substitute for Fuji's chain.   The cross-examination of Mr Neale went thus:
Q.  Let us assume it has the meaning that you suggest and I really will not go back on that; there is no suggestion to use a belt, is there? 
A.  No. 
Q.  And it is the same problem that I put to you about Honda: there was no body of knowledge as to using a belt for lubrication? 
A.  No. 
Q.  Therefore, can you advance any reason why the uninventive person following Fuji would adopt a belt? 
A.  Not following Fuji alone, no.
53.	There is, I think, confirmation of the fact that Fuji 1 missed the point from Fuji 2.   This is for vertical crankshaft OHC engine.   Again he wants to do away with an oil pump.  But this time Fuji does address lubrication of the camshaft.  It is achieved by the use of two sumps, one below the big end and one below the camshaft.   Oil is picked up by splash from the big-end sump and carried by the chain to the head where it falls into the sump there.  The camshaft has its own "oil scraper" (i.e. splasher).   
54.	Self-evidently the differences between Fuji 2 and the inventive concept of the amended claim 1 are greater than in the case of Fuji 1.  It would take a leap of the imagination to turn the engine through 90o, do away with the sump for the head, and realise that the chain would carry enough oil to lubricate the head and then substitute the chain with a belt.
55.	I would add this in relation to Fuji 1: that it comes a lot closer to teaching or suggesting "wet the chain" (which is but a trivial step from "wet the belt") than does the patent in teaching or suggesting "wet the belt."   If I were wrong on construction, then I would be correspondingly wrong on Fuji 1 with the result that claim 1 would be obvious.
The P25 engine
56.	I turn to the P25.  There was no real dispute that it was sensible to assume that the skilled man would look at the engine itself and its instruction manual.   By 1995 he would know that it was obsolete and bear that in mind.   The engine is of the horizontal crankshaft type.  It uses a timing chain within the casing.   There is a specially designed oil guide for getting oil to the head, there being splash lubrication of the chain.  The manual says "The oil which becomes adhered to the cam chain tension roller and the cam chain drops into the oil guide and is sent to the head."    It is not self-evident from the papers that you do not need an oil guide.  In fact if you made a serious study of the engine you would discover that probably no oil guide was necessary because, as the defendants' first video shows, the chain carries a lot of oil.  But I do not think that would be self-evident to the skilled man.   Why should he do such an experiment?   
57.	Thus although the P25 comes some of the way towards the inventive concept, I do not think it comes far enough.   You have to do away with special guide, put the engine through 90o and use a belt instead of a chain.   That is too much for the skilled man to see, and all the more so given that the P25 was obsolete.
Fichtel & Sachs
58.	This is closely contemporaneous with the patent in suit and the Honda GC engines.  It was the result of the same environmental control pressures as led Honda to develop the GC engines.  There is a US Patent No.5,447, 127 and there was actual prior use in 1994 of an engine in accordance with the patent.
59.	The engine is horizontal.  A special camshaft sump is provided in addition to a sump at the crankcase end.   The point of the camshaft sump is to provide lubrication via a dipper fixed to the camshaft.   The patentee is concerned about the camshaft sump losing oil when the mower is on a slope.  He envisages transport of the oil to the camshaft sump by the chain. 
60.	It is true that the Fichtel and Sachs patent (though not the actual device) mentions use of a belt as an alternative to a chain, but there is no disclosure of the simple idea that a belt or chain splashed near the big-end will lubricate the head without more.   Mr Neale's cross-examination went thus:
Q.  Could I suggest to you that there is nothing that would indicate to this man we have talked about a lot -- the notional skilled man -- nothing to suggest to him that he could dispense with that second sump? 
A.  No I agree. 
Q.  Therefore, you could not have a horizontal shaft engine using the Fichtel & Sachs idea? 
A.  No, you could not, but the Fichtel & Sachs idea does teach you that the moving chain provides a balance in oiliness between its two ends and that will apply whether it is horizontal or vertical. 
Q.  Yes.  But what you do not get out of Fichtel & Sachs is that you do not need a sump at the camshaft end? 
A.  Yes. 
Q.   And if you looked at the engine, you would see that they are clearly relying on the sump [sprocket, I think it must be, the transcript says "pointer2"] because it has the scoops? 
A.  (Witness nods) 
Q.  So there is nothing in Fichtel & Sachs to lead you to the design of the Honda GC engine? 
A.  No, it is a total different engine layout. 
Q.  I meant in terms of the lubrication? 
A.  In terms of lubrication.  No I do not think so, except that it does prove to me the ability of a chain or belt -- particularly a chain -- to distribute oil between its two ends. 
Q.  Yes. 
A.  Which is relevant to the Honda design. 
Q.  Yes, but -- and this is where the sort of lawyer approach comes in -- just looking at Fichtel & Sachs, it gets you some of the way but they did not see the final step, agreed? 
A.  Yes.
Obviousness - conclusion
61.	I conclude that the concept was non-obvious.   I am confirmed in that view by the fact that Mr Shimizu applied for a patent for the GC engine.  He said this:
"…in the case of an OHC engine the structure is one in which the camshaft is in a head part of the engine main body which is separate from the crankcase, and so there is the problem that the valve drive cams and least a portion of the timing valve drive system are located in positions which are distant from an oil reservoir and there is insufficient lubrication of the timing valve drive system."
62.	Mr Shimizu clearly thought he had solved a problem.  He was proud of his design.  He was right to be so.
Amendment   
63.	There is no objection to the proposed amendment to claim 1.  Nor is there any objection to proposed new claim 2 on the basis that the words at all times when the engine is in operation are omitted.  On that basis the new claim is no more than the previously dependent claim 7 written out as an independent claim.  It is allowable. It reads:

“2.	An internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting the crankshaft and camshaft via respective pulleys, wherein the timing belt is adapted entrain a sufficient quantity of oil from the sump to lift it to the cylinder head for lubricating purposes and comprising a toothed pulley, the teeth of which run over apart of the rotation within a restricted passage and a belt having mating teeth which also run for part of their movement within a restricted passage, these runs being guided to a meshing point at which oil is pressurised as a result of the meshing action”.
64.	I turn to proposed amended claim 3, to which objection is taken, but only if claim 1 were held invalid.     Mr Prescott devised a point which ran like this.    The proposed amended claim is wider than any of the existing sub-claims, although it falls within the scope of the original claim 1.  If claim 1 is invalid, it confers no protection and never did so.   Accordingly the proposed amended claim "extends the protection [of] the patent, contrary to s.76(3)(b) of the Act (corresponding to EPC Art 124(3)).
65.	If the argument is right one does not even have to consider whether the amendment results in the specification disclosing additional matter contrary to s.76(3)(a) (EPC Art.123(2), 138(1)(d)).   The practical consequences of the argument are significant.  It frequently happens (particularly during opposition) that amendments of this sort are proposed on the basis that the original, wider claim, is not defended. All the argument then centres on the proposed amended claim.  No-one bothers with the original claim.  But if Mr Prescott is right, they should.  For, if that is invalid, the scope of protection is being extended.   Moreover, if the amendment is allowed when the original claim 1 was invalid, then the whole patent is invalid on the grounds that the protection has wrongly been extended (s.72(1), EPC Art. 138(1)(d)).   So, Mr Prescott says the validity of all claims wider than the amended claim must be investigated to see whether the amended claim extends protection.
66.	I reject the argument.   Like patents themselves, the EPC and the Act must be read purposively.   The "protection conferred" can mean either the protection actually given, taking into account validity, or merely "the scope of the claim" as a matter of language, i.e. the scope assuming validity.  Art 69 says "the extent of protection conferred by a European patent shall be determined by the terms of the claims."   That points very strongly to the latter meaning in the context of the EPC and so in our Act.   Nor can I see any purpose in Mr Prescott's meaning.   Anyone doing an act falling within a wide claim of a patent must (and in practice does) consider what might happen if the claim is bad.  He must look at the subsidiary claims and he must consider what possible amendments might be made, amendments which, of course, do not add matter.   He is at liberty to attack the patent in its unamended form and thereby force the patentee to formulate amendments if the original claim is bad.
67.	I turn to Mr Prescott's second objection to amended claim 3 - that of added matter.  For this point it is necessary to set out the proposed amendment:

2.3	An internal combustion engine according to Claim 1, wherein an oil pulley is provided below the crankshaft pulley positioned to be immersed in oil within the oil sump for entraining oil therefrom or 2 having means for supplying oil to the timing belt comprising a rotatable member adjacent to the crankshaft which, in use, picks up oil from the sump associated with the crankshaft.
  His argument, as set out in his skeleton argument is as follows:  
“That is not a valid intermediate generalisation and adds subject matter.  As granted, the patent disclosed an "oil pulley" 7 (see Fig. 2) with an arrangement of ports 17.  In use, the oil is "forced" by a combination of inertia and a "squashing action" (page 47-14).  The point is that oil is driven under pressure, and not just lifted, and this is entirely consistent with the interpretation of claim 1 we have urged above.  But, according to the amendment, this concept is now expanded to a mere " rotatable member".  It covers and is intended to cover e.g. a bladed splasher, such as is used in the Honda engines in suit.  These are two different concepts: delivery under pressure vs. splashing, and there is no basis whatever for the latter in the patent as granted”. 
68.	I agree.  Mr Watson accepted that the amendment was a generalisation of what is specifically disclosed.  He said that this amendment was merely one which covers more than an earlier claim and not one which adds to the disclosure, relying on Texas Ironworks Inc'.s Patent [2000] RPC 207.   He says the new wording covers, inter alia, a rotating splasher driven from the crankshaft rather than the belt but does not actually disclose any such arrangement.  I disagree.    The claim sets forth for the first time a generalisation of oil pick up which is nowhere disclosed before amendment.   A rotatable member adjacent to the crankshaft clearly brings to mind a splasher driven by the crankshaft.   Such a splasher is no-where mentioned prior to amendment. So a wholly new idea is dropped from out of the blue into the claim.  That is adding matter to what was originally disclosed.  There is a new combination disclosed as well as claimed - a combination which the patentee had never contemplated.
Conclusion
69.	In the result I hold that:
(1)	The amendment to claim 1 is allowable;
(2)	The new claim 2 is allowable;
(3)	The amendment to claim 3 is not allowable;
(4)	The patent is not infringed.
(5)	The patent as proposed to be amended (save for new claim 3) is valid.