England and Wales High Court (Technology and Construction Court) Decisions

IN THE HIGH COURT OF JUSTICE
CHANCERY DIVISION

		28th April 1997

Mr. Justice Laddie:

The first plaintiff, Lars Erik Norling, is the proprietor of European Patent (UK) No. 0,358,671. The second plaintiff, Proman Technology AB, claims to be the exclusive licensee under it. The patent is concerned with a process and equipment which is designed to help speed up and facilitate the de-boning of animal carcasses in abattoirs. The patent is exploited by the plaintiffs by the manufacture and sale of de-boning apparatus under the name the Carni Liberator System. The first defendant, Eez-Away (UK) Limited, is the UK distributor of de-boning equipment manufactured by an associated company in Ireland. The proceedings against the second defendant have been discontinued. The third and fourth defendants operate Eez-Away de-boning equipment within the jurisdiction. They were not separately represented before me. In effect this action has been conducted as if it was between the plaintiffs and the first defendant. The plaintiffs assert that the process utilising the Eez-Way equipment infringes the patent and the present proceedings have been commenced accordingly. Initially the defendant attacked the validity of the patent and counterclaimed for revocation. Partly in response to that attack, the first plaintiff sought leave to amend the patent and a timetable was set to enable the infringement and validity issues to come on to be tried at the same time as the amendment issues. Subsequently all the defendants abandoned the attacks on validity. However the first plaintiff wished to continue to pursue his application to amend. On the application to withdraw their counterclaims the defendants argued that, once leave to discontinue had been given, the court retained no jurisdiction to entertain the application to amend. This matter was considered by Jacob J. He held^[1] that the court did retain jurisdiction. It follows that the issue of amendment is still live before this court.

The plaintiffs' patent

Whereas in the past, much of the preparation of cuts of meat was performed by skilled butchers in local shops, the structure of the meat trade has altered and much more de-boning and preparation now takes place in the abattoirs. Here very large carcasses need to be manipulated in a way which makes it easier for the abattoir butchers to work on them. Mr. Norling's patent is concerned in particular with a semi-automated process and equipment which facilitates the removal of bones without damaging the meat. The patent only describes one embodiment of the invention. Unfortunately that description is not extensive. Furthermore the United Kingdom patent has been translated from the original into a language which Mr. Norling accurately suggested lay somewhere between the King's Swedish and the Queen's English. Many of the amendments proposed are designed to correct errors in translation and to render the whole document significantly easier to read. Notwithstanding these shortcomings, the overall operation of the process and equipment is not difficult to understand and can be explained by reference to drawings which form part of the specification and which are reproduced below:



(A) and (C) are side elevation views of the equipment. (B) is a plan view. The carcass (2) is carried on a hook (3) which is referred to in the specification as the "meat hook". The meat hook is carried on a conveyor (1). The suspended carcass moves to the right to a work station. Here, another hook (4), referred to in the specification as the "second meat hook" or "second hook" is attached directly, or indirectly by way of a joint (13), to a part of the carcass which it is intended to separate from the rest. The second hook is carried either on the same or another conveyor, so both hooks and the carcass can move towards the right. As depicted in the drawings, the second hook is carried at the end of a support which, in turn, is carried on the conveyor. The specification then continues, as follows:

"In the next instant either a pushing arm 7 or a pulling arm 7 (below called the arm) is applied on the carcass or on the meat-hook. ... The arm is mounted on a driving means 8. The arm transports the carcass 2 onwards along the conveyor."

The force applied by the arm is sensed by means of a load cell (9). The force applied by the arm puts the carcass under stress between the meat hook and the second hook. This makes it easier for a butcher to cut away the part to be separated which ends up suspended on the second hook and carried by its conveyor.

The specification also contains passages relating to the adjustment of the force applied to and the speed of the second hook. These are matters of some importance and will be considered separately below.

The defendant's apparatus and process

Although a detailed process description was served in the action, the overall form and operation of the defendant's apparatus is most easily described by reference to the defendant's own patent specification and drawings which describe it. Where possible I shall adopt the same terminology for parts as is used in the patent in suit.

The Eez-Away system employs two de-boning stations. Their location is shown at 5 and 6 on the plan drawing below. The direction of movement of the carcass is depicted by the arrows.



What happens at the first boning station is illustrated in Figure 3 below:



A carcass approaches the station suspended from a conveyor (1) by a meat-hook (12). As the carcass moves to the right, a pneumatic ram (33) lowers a pivoted rod (30), at the end of which is a chain (36) carrying a second hook (35). This second hook is attached to a part of the carcass which is to be removed, e.g. a bone.. The pivoted end of the rod is connected to a stationary post. As shown in Figure 4 below, the meat-hook (12) is carried on a bogie with wheels (13).



As the bogie moves to the right (the carcass may be pushed by the operator), it passes under a hinged flap or finger (40). This is illustrated in Figure 5 below:



Once the bogie has passed under it, the finger falls back to the vertical. The finger, which cannot rotate further than that in a clockwise direction because of back-stop 43, is carried on a double-acting ram (45). This can be operated to push the finger (40) to the right. When it comes up against the rear surface of the bogie of the meat hook, it pushes it to the right. In other words the force of the ram (45) is transmitted via the finger (40) to the meat hook (12). This has the effect of tensioning the carcass between the meat-hook 12 and the second hook 35. In turn this helps the butcher when he cuts away the part to be discarded which is left hanging at the end of the chain (36). That part is lifted of the hook 35 by a butcher and carried to another part of the abattoir either for further manual processing or disposal. The bogie and hook (12) carrying the remainder of the carcass proceed on along the conveyor (1) to the second de-boning station. Here also a second hook arrangement is operated. However in this case the there is a transport rail (60) which co-operates with the second hook;

"allowing [it] to travel on the rail 60 to direct a carcass to cutting or trimming stations for further processing, if desired."

This loop rail is illustrated in Figure 1 above.

The patent claim.

The plaintiff now only alleges infringement of claim 1 of the patent. This is a process claim. It is said that the third and fourth defendant have operated the process in the jurisdiction and the first defendant has infringed in accordance with s. 60(2) of the Patents Act, 1977. Because its language is easier to understand, it is convenient to consider the claim in its proposed amended form.

"1. A method for continuous separation of skeleton parts from a carcass, whereby the carcass hangs on a meat-hook which is brought forwardly along an overhead conveyor (1), and where a second meat-hook or similar means is attached to a part of the carcass with a force opposite the running direction of the overhead conveyor (1), characterised in that an arm (7) is arranged so that it simultaneously, when said force effects the carcass, presses the carcass forwardly in the running direction of the overhead conveyor (1) so that the skeleton part is separated, and further characterized in that the second meat-hook is attached on the same or another overhead conveyor, whereby the part when separated runs along in a continuous course, that the driving force and the speed of the arm are regulated independendly (sic) of each other, and that the second meat-hook is held static at the overhead conveyor by way of a support when the skeleton part is being separated from the carcass"

The arguments advanced for and against infringement centred on three parts of this claim namely; (i) whether the arm presses the carcass forwardly, (ii) whether the second meat-hook is attached on the same or another conveyor and (iii) whether the driving force and speed of the arm are regulated independently of each other.

(i) "The arm presses the carcass forwardly"

The plaintiff's case is that in the Eez-Away apparatus, the arm is finger (40) which pushes or urges the bogie, and thereby the carcass, forwardly. This is within the natural scope and meaning of the words of the claim. In particular the defendant relies on an illustration, reproduced below, of the forces applied to the carcass as a result of the interaction of the two hooks and the arm and to the following part of the specification:

"The arm 7 which is positioned 30 to 60 cm down on the carcass, counted from the top side of the conveyor, forces the carcass to remain on the meat-hook, while this and part of the carcass to be released are exposed to the driving force of the arm. The arm functions as support by way of the force 12 shown in figure [6] for the force 11, see also figure [6], which would otherwise have pulled the carcass off the hook."

This quotation is in the form proposed by amendment. It is still not perfect.



Based on this passage and the drawing, the defendant advanced an elaborate argument that the arm has to exert force on the carcass directly, that is to say it must touch the carcass. This it is said is necessary to stop the carcass rotating and coming off the meat-hook (3). In support of this case the Defendant filed evidence by its expert, Mr. Sheridan. He examined a piece of prior art, referred to in the evidence and during the trial as "Korhonen", and noted what he thought were the differences between this and the plaintiff's patent. These he identified as (i) the use of an arm pressing on the carcass below the meat hook and (ii) the concept of independent regulation of speed and force. He said that both of these struck him as important concepts in the patent. He noted that in the Swedish patent office Mr. Norling had emphasised the importance to his invention of the use of the pushing arm and then went on to treat the invention as if the use of the pushing arm to prevent rotation of the carcass about the hook and removal from the hook was an essential feature.

As against this, the plaintiff points to the passage in the specification, quoted in this judgment just after Figure 1 above, which says expressly that the arm can press either on the hook or the carcass. This passage was referred to by Mr. Sheridan who dismissed it with the statement:

"If the arm were applied to the meat hook at any point above the place where the hook is attached to the quarter, then this would not work at all: The quarter would rotate (either about the point where the hook is suspended from the overhead rail, or about the point where the meat hook enters the hanging quarter) so as to make boning difficult or impossible; and the quarter would perhaps be lifted straight off the hook."

This evidence is irrelevant. The meaning of the claims is a matter for the court. Mr. Sheridan's views of what Mr. Norling said in his home patent office are of no value at all. Furthermore Mr. Sheridan's evidence on this point was unconvincing. There is in my view nothing in the specification which suggests that prevention of rotation of the carcass is an essential integer of the invention. Indeed, not only is that feature not referred to in the claim, it is not referred to anywhere in the specification either. The only explanation given for choosing to apply the arm directly to the carcass is to help the carcass remain on the hook. This is not put forward as a major benefit and it is apparent that it is trivial. The risk of the carcass coming off the hook in normal operation, which must be slight, can be overcome either by applying the arm to the carcass when the hook is applied in the direction shown in Figure 6, or by simply reversing the direction of the hook, as shown in Figure 1 or, by simply changing the depth of the design of the hook.

In my view the plaintiffs are right in relation to this issue. When the claim stipulates that the arm presses the carcass forward, there is no requirement that it touches the carcass. The passage in the specification describing the arm as pressing or pulling on the carcass or the hook is consistent with this meaning. The operation of finger (40) in the Eez-Away apparatus fulfils this requirement of the claim.

(ii) "The second meat-hook is attached on the same or another conveyor"

In relation to this feature, it is necessary to consider the first and second de-boning stations in the Eez-Away apparatus separately. The claim requires the second meat-hook to be "attached on the same or another overhead conveyor, whereby the part when separated runs along in a continuous course". At the first de-boning station, the second meat-hook (35) is not attached to a conveyor at all. Since this is so the separated part attached to this hook also does not run along a continuous course. On the contrary, as mentioned above, it is removed manually from the hook by a butcher. The defendant says that for these reasons operation of this part of the Eez-Away system cannot infringe.

The plaintiff agreed that if the words of the claim were given their natural meaning, then for the reasons advanced by the defendant there could be no infringement. However Mr. Miller QC, who appeared for the plaintiff, suggested that such a rigid approach was not appropriate. He said that what counted was whether the separated part runs along a continuous path. Since the only separated part which could be of any interest was the one which had the majority of meat attached to it and needed further processing and since in the Eez-Away process that was still mounted on a hook and conveyor and passed on to the next de-boning station, the substance of the invention had been taken. He argued, and put to Mr. Sheridan in cross-examination, that there was no good reason why anyone would want a conveyor to remove the detached bone at the first de-boning station. This argument is hopeless. The claim makes it clear that the first meat-hook is mounted on a conveyor. It then requires the second hook to be mounted on a conveyor as well. Whether or not that is the same conveyor as is used by the first meat-hook is immaterial. It is not construing a claim or the monopoly secured by a patent to ignore one of the characterising features of the invention. Since the second hook is not mounted on any conveyor, the operation of the first de-boning station does not fall within claim 1. Whether mounting the second hook on a conveyor is very useful has no relevance to construction.

At the second de-boning station there are two conveyors, one carrying the first meat-hook, the second, in the form of a short loop (shown as (60) in Figure 2 above), being used for onward movement of the separated meat hanging on the second hook. A video film of a demonstration of the Eez-Away process made for the purpose of these proceedings shows the butcher removing the meat from the second hook at the second station as soon as it has been separated from the rest of the carcass which remains on the first meat-hook. Based on this Mr. Platts-Mills QC, who appeared for the defendants, said that the separated part of the carcass did not run along on a continuous course as required by the claim. However, it became apparent during the course of the trial that this argument was based on a misconception. Although the meat was shown being removed from the second hook at the second station, this was because carcasses had been removed from chill storage for the purpose of the demonstration and then had to be returned to such storage as soon as the cutting was complete. In commercial operation, the meat is not removed from the hook but passes round the loop for further cutting and preparation. Notwithstanding that, Mr. Platts-Mills refused to accept that the second hook was supported by a conveyor or that it progressed further in a continuous course. The precise basis for this refusal was not made clear to me.

In my view, this feature of the claim is present and utilised at the second de-boning station of the Eez-Away apparatus.

(iii) "The driving force and the speed of the arm are regulated independently of each other."

This was the most important issue during the trial. Absent any material in the specification which points in another direction, these words in the claim appear to me to be tolerably clear. The claim is for a process. This part of the claim is concerned with what happens to the driving force of the arm and the speed of the arm during the process. The 'force of the arm' must be a reference to the force applied by the arm to the carcass. That force and the speed of the arm are regulated. That means they are adjusted. Furthermore each is adjusted independently of the other. Prima facie that means that the driving force can be adjusted without affecting the speed of the arm and vice versa.

If that is what this part of the claim means, then, as Mr. Miller accepted, there can be no infringement. To understand why this is so it is necessary to explain in a little more detail how the Eez-Away apparatus functions. As already mentioned, force is applied to the carcass carried on the first meat-hook by means of the finger (40) depicted in Figures 3, 4 and 5 above. It is the latter of these which shows the finger in its pushing position. The finger is driven by the ram (45) which is attached to a pneumatic cylinder. The way in which the latter works can be explained by reference to the following, highly schematic, drawing. This shows a standard pneumatic cylinder with a piston rod, rather than a rodless pneumatic cylinder as used in the Eez-Away apparatus. But the principle of operation is the same.



The finger (40) is moved as a result of the forces applied to the piston. The cylinder is in a circuit to which pressurised gas is supplied. There is a regulator which is adjusted from time to time to control the pressure of the gas which can be supplied from the circuit to the cylinder. In normal use, the pressure used to operate the cylinder is set by a mechanic at or about 6 bar. Atmospheric pressure is 1 bar. If pressurised gas is supplied to the left cylinder and the right cylinder is open to the atmosphere, there will be a 5 bar pressure difference between the two cylinders which will force the piston and its attachments (shown in the illustration as a piston rod) to the right. The greater the pressure difference between the two cylinders, the greater the force which the piston can apply to the piston rod. In the Eez-Away system, the pneumatic cylinder is operated to apply force to the finger. This has two effects. First, it causes the finger to move. Secondly it applies force to the hook holding the carcass. The greater the pressure of the gas supplied to the left hand side of the cylinder, the greater the force which can be applied to the hook and the greater the speed with which the hook will move. The pressure of the gas is adjusted so that the force applied to the hook can not reach a level at which it will tear the carcass between the two hooks. At the point at which the maximum permitted force applied to the finger matches the resistance of the carcass to further pulling apart, the forward motion of the finger and hook will stop, although the force applied to them will continue to be at the maximum permissible in the system.

Sometimes in operation the hook will move too fast for the butcher who is cutting the carcass. He has a toggle which he can use which stops the further motion of the finger/hook arrangement. This is achieved as follows. At the moment the toggle is pulled, the left fluid inlet/outlet is blocked. No further gas is allowed in and none is allowed out. The left cylinder is now a closed space, initially filled with gas at about 6 bar. If the right hand cylinder was still open to atmosphere, initially the piston would continue to move to the right. That would have the effect of reducing the pressure in the closed left cylinder. Eventually that rightwards movement of the piston would stop at the point at which the force applied to it on the left side by the trapped, but partially relieved, compressed gas was matched by the force applied to it on the other side by the combination of atmospheric pressure (1 bar) together with the tensile force built up in the stretched carcass. In fact operation of the toggle does not leave the right hand cylinder open to the atmosphere. Instead it is connected to the pressurised gas supply at about 6 bar. The result of this is that the forces tending to push the piston towards the left, namely the pressurised gas together with the tensile forces in the carcass, initially exceed the forces pushing in the other direction caused by the trapped pressurised gas in the left cylinder. The piston therefore starts to move back to the left. As it does so, the gas in the left cylinder is further compressed. Its pressure therefore rises. At the same time the tensile forces in the carcass are, to some extent, relaxed. The leftwards motion of the piston will continue until a position is found when the forces on either side of the piston are the same. This effect can be seen on a video of the Eez-Away apparatus being used. When the toggle is operated, the forward hook stops moving to the right and comes backwards a distance.

There is one other feature of the Eez-Away apparatus which was the subject of debate. On the first versions of the defendant's equipment, there was a needle valve fitted. This is a device which is capable of adjusting the size of the exhaust exit from the right hand cylinder. If closed down completely, it will stop any gas exiting the right cylinder. If it is opened completely it allows the gas in that cylinder to escape rapidly to atmosphere. The purpose of this was, apparently, to allow the speed at which the hook moved to the right to be adjusted. During operation, if gas is impeded in its exhaust from the right hand cylinder, a back pressure will be created in that cylinder because the gas in it will be compressed. The result will be that the difference between the pressures in the left and right cylinders will be less than in the situation where the right cylinder is at atmospheric pressure. This means that net force pushing the piston in the right hand direction will be reduced and, as a consequence, the speed of movement to the right will be reduced also. Of course if the force applied to the carcass gets towards the maximum permissible, the forward movement of the finger and hook will be reduced and eventually will stop. Gas will continue to leak past the needle valve until the contents of the right cylinder are at atmospheric pressure. At that time the rightward force applied to the finger and hook will be exactly the same as in a case where the needle valve is fully open. In other words the maximum force which the piston can apply to the finger and hook is the same.

This needle valve is located out of reach of the operator in a locked cabinet above his head. It is not adjusted in practice because, according to Mr. Sheridan, it was found to be ineffective to control the speed of the hook at the only point where Eez-Away wanted to control it, namely after the two pieces of carcass had been separated. It had never been designed to control the speed of the finger/hook during the de-boning operation. In any event, later versions of the equipment do not have the valve. It is not suggested that the second and third defendants have ever adjusted the needle valves which are present on their Eez-Away equipment. It is not suggested that the first defendant has ever taught any customer to adjust the needle valve. Nor has it been suggested that it is obvious to a reasonable person, for example a customer for the Eez-Away apparatus, that the needle valve is suitable for adjusting the speed of the finger/hook or is intended to achieve that effect.

On these facts it is impossible to say that the words in claim 1 "the driving force and the speed of the arm are regulated independently of each other", if given their normal meaning, are met by the Eez-Away apparatus and process. Although, as the defendant accepts, the pressure to the cylinder is capable of being adjusted and is in fact adjusted from time to time thereby affecting the force applied to the finger/hook, it is clear that adjusting the force will also adjust the speed of the finger/hook. The force is not adjusted or regulated independent of speed. Further, in practice there is no adjustment or regulation of the speed at all and, even if the needle valve was operated (which it is not), it would affect both speed and force simultaneously.

However Mr. Miller suggested that a different meaning ought to be given to the relevant words in claim 1. He said that 'regulate' is a broad word and it covers any sort of control, for example, control of the on/off type or of the infinitely adjustable type. He argued that claim 1 is not limited to regulation of the infinitely adjustable type. Furthermore he said that even if there was no adjustment possible at all, if the apparatus happened to have a particular fixed maximum it was to be regarded as "regulated". Therefore even on the Eez-Away apparatus without needle valves on the exhaust side of the piston, there was a maximum speed of exhausting the cylinder which would have the effect of imposing a maximum speed on the movement of the finger. It was therefore regulated. Furthermore he said, that what counts is the regulation of the maximum force to be applied to the finger. He said that in the Eez-Away apparatus, that could be adjusted. The apparatus could still exert the maximum force even if there was no forward movement of the finger/hook. As to the requirement that force and speed must be "independently" regulated, he said that this means "separately" regulated, i.e. a control for force and a control for speed. Since the force regulator in the defendant's apparatus is separate from the speed regulators (by which I assume he meant the needle valve), this feature of the claim was present. This view of construction was said to be consistent with the description in the specification.

The only passage in the specification dealing with this issue is as follows:

"The driving means 8 which is separated from the overhead conveyor 1 drives the pushing arm or the pulling arm back and forth along the overhead conveyor.

Start and stop of the driving means are regulated partly manually and partly by way of mechanical or inductive limit position indicators.

The driving means can be started and stopped by operations from the butcher. When the arm 7 has reached its outermost limit position it automatically returns.

The driving force and the speed of the arm can be regulated independently of each other by way of the load cell, so that they do not exceed the limit when tear damages occur on the meat in the carcass. The arm stops but continues to exert a maximum allowed drawing force on the carcass, when a force greater than the maximum allowed is required in order to continue the transport along the conveyor.

The speed with which the carcass is driven is adjustable and it is completely independent of the allowed maximum tensile force. As long as the force required falls below the maximum allowed the carcass is driven with the adjusted speed."

The meaning of all this is by no means clear. Although the specification discusses the regulation of force and speed, no example of how this can be achieved is included. One has to make the most of this passage without the benefit of additional assistance. However it appears to me that at least one thing is tolerably clear. This passage treats the stopping and starting of the equipment effected manually by the butcher as something quite different to the regulation of the speed and force. The question is then, what does 'the driving force and the speed of the arm can be regulated independently of each other" mean. This is substantially the same wording as appears in Claim 1. First it is apparent that the inventor has in mind that each is adjustable. This is no support for Mr. Miller's argument that a fixed and immutable maximum for speed means that the speed is "regulated".

Further this passage seems to contemplate that the adjustment is different for force and speed. The regulation of the force appears to be a reference to imposing a maximum on the drawing force on the carcass. This is to avoid tearing of the carcass. Therefore the equipment is set up in such a way that the maximum force which can be applied to the carcass can be regulated, that is to say it is adjustable. As far as the speed is concerned, this also is adjustable. The carcass can then be driven at the "adjusted" speed. The speed in issue is therefore the speed when the carcass is being moved. Consistent with what I have said above, it has nothing to do with the fact that the movement of the carcass can be stopped by the butcher at the de-boning station. The selection of a suitable speed is a matter for the butcher.

If it was permissible to construe the words of claim 1 so as to be more easily consistent with this passage in the specification, in my view it would still require the following features to be present:

1. An adjustable maximum force which could be applied to the arm

2. An ability to vary the speed with which the arm is moved

3. Adjustment of the maximum force would have to be independent of, i.e. have no effect on, speed and vice versa.

I am not persuaded that it is permissible in this case to lift words out of the specification for the purpose of changing the clear meaning of claim 1. But even if it was, the Eez-Away apparatus and process would not infringe because features (2) and (3) above are absent. It follows that on either construction the plaintiff's claim fails.

In these circumstances it is not necessary to consider Mr. Platts-Mills' arguments that the second plaintiff is not an exclusive licensee and that the plaintiffs' right to damages is restricted by virtue of late registration of the licence.

Amendment

The amendments sought fall into two categories. The majority consist of changes in wording which either more accurately accord with the original Swedish text of the specification or which are designed to make the text more clear. The second consists of the addition of two new subsidiary claims which were designed to provide the plaintiff with a fall-back position if the defendants had pursued their invalidity attack and had succeeded in knocking out claim 1.

The defendant's objection to the first category of amendments centred on an assertion that any amendment which truly clarifies or explains the specification must be adding matter to the specification and were therefore is not allowable. Furthermore Mr. Platts-Mills put forward a raft of reasons why the discretion to allow amendment should be exercised against the plaintiff. These included the following; (i) the defects, and in particular the trivial ones, are legion and would have been readily apparent to any careful reader, (ii) there is no evidence from those responsible for the defects, (iii) the plaintiff has delayed in making the application and (iv) the plaintiff has made reference to the patent and its effect to potential customers for the purpose of attempting to persuade them to purchase his equipment.

I can deal with all of these fairly briefly. The proposition that all amendments made to clarify text must be adding matter, in the s. 76 sense, is false. Where the meaning of the text is not altered by the amendment, then it adds nothing. That is the position here. The effect of the amendments is to remove some of the pigeon English and replace it with text which reads more easily but means the same thing. Objection (i) is without substance. It would be very strange if a court was to refuse amendments to put the specification into English simply because there were a lot of them. That stance would not affect the validity or scope of the patent. I can see no reason why the discretion should be exercised so as to ensure that future readers are subjected to the discomfort of reading a poorly worded text. In view of this, objection (ii) has no weight either. Objections (iii) and (iv) fail on the facts. I will allow those amendments

The second category consists of the application to add the following two new subsidiary claims:

"2. Method according to claim 1 further characterised in that the arm stops but continues to exert a maximum allowed drawing force on the carcass when a force greater than the maximum allowed is required in order to continue the transport along the conveyor.

3. Method according to claims 1 or 2 further characterised in that the speed with which the carcass is driven is adjustable and as long as the force required in order to continue the transport along the conveyor falls below the maximum allowed, the carcass is driven with the adjusted speed."

In the plaintiff's statement of reasons, it was said that the addition of these new claims "clarify and better define the invention" and "the proposed new claims could have independent validity over claim 1 and thus their inclusion will strengthen the patent". No objections, other than those set out above, were taken by the defendant to these amendments. However at one point it seemed to me that it would be difficult to decide whether they would achieve their objective of strengthening the patent if I had been presented with no arguments that the patent was weak. Since the onus is on the patentee to justify amendment, it could be argued that failure to make out the grounds put forward in the statement of reasons should weigh against leave being given. On the other hand this would produce a very strange result. Either the plaintiff would have to put in evidence suggesting that the current claim 1 is weak or the amendment could be refused and the plaintiff would be left to seek the same amendment again, perhaps years from now, when some other potential infringer attacks validity. As Mr. Miller pointed out, if the latter course was followed an opponent could argue that there had been unreasonable delay in seeking amendment. Furthermore, if there is any risk that claim 1 is invalid and the amendment is not allowed now, this might affect the plaintiff's right to damages in the future.

Although the court can exercise its power to refuse to permit amendments which are pointless, I am not persuaded that this is such a case. Both the proposed subsidiary claims are of narrower scope than claim 1 and, even if the pressing need for them has passed now that the defendant has jettisoned its validity attack, I have come to the conclusion that they are proper amendments for the plaintiff to make. There is no matter which has been drawn to my attention which persuades me that I should exercise my discretion to refuse leave.

It follows that I shall allow all the amendments which have been proposed.

Note 1   Norling v. Eez-Away (UK) Ltd. [1997] RPC 160.    [Back]