Ferag Ag v Muller Martini Ltd.

The target readership of a patent is that of people "likely to have a practical interest in the subject matter of the invention" with "practical knowledge and experience of the kind of work in which the invention was intended to be used" (Catnic v. Hill & Smith [1982] R.P.C. 183 at 242-3). So in order to interpret a patent, the court must equip itself with the practical knowledge and experience of the target readership. This body of knowledge is called "common general knowledge". This is not "general knowledge" in the sense in which most people understand it, but:

"what would in fact be known to an appropriately skilled addressee - the sort of man, good at his job, that could be found in real life."

General Tire & Rubber Co v. Firestone Tyre & Rubber Co Ltd [1972] R.P.C. 457 at 482.

It is, therefore, the technical background and mental equipment which it is necessary to have in order to be competent in the field of science or technology in question. It includes not merely what is in the skilled addressee's head, but also what is contained in frequently used text-books or trade literature. The text-books to which the experts referred were, naturally enough, in German; but the skilled addressee is not monoglot.

Since I must interpret the patent as it would be understood by the skilled addressee it is convenient to consider the attributes of the skilled addressee before coming to the patent itself. Professor Fritsch says the skilled addressee is a mechanical engineer with a degree in engineering with about 5 years of experience in designing print finishing machines or who works in production and considers the improvement of finishing machines. Alternatively he thinks it could be a more experienced engineer without formal qualification. Professor Lüthi thinks that in addition to a degree in mechanical engineering the skilled addressee would have a minimum of 3-5 years' industrial experience in the field of paper processing machinery. Experience in machine tool engineering would be an additional benefit. He thinks that a more experienced engineer with work experience in a corresponding field could work on the development of the machines as well. No one suggests that there is any relevant difference between the experts in this respect. The patent has a priority date of October 1988; with the consequence that the common general knowledge must be assessed as at that date.

Both experts broadly agree that there are three kinds of cut: a knife cut, a shear cut and a burst cut. However, a knife may cut in one of two ways: either by itself slicing through the printed product; or by being in cutting engagement with another knife which slices through the product.

A burst cut is most suitable for flexible materials. The material is held between two clamping points. It requires no cutting table or counterknife.

The forces exerted by a cutting knife will tend to move the printed product being cut. To resist this movement it is usual to clamp the product by clamping means located as close as possible to the cutting line of the knife.

In addition a cut may be an "open" cut or a "closed" cut. Punching (which is a closed cut) is a sub-group of the "single-knife cutting principle". An example of a practical use of this punching mechanism is the punch-cutting (punching) of playing cards in order to make the corners rounded. Other examples include the punch-cutting of labels or tabbed, indented books, including dictionaries or large reference books which have the successive letters of the alphabet indented into the pages on the front edge. With punch-cutting, the cut occurs basically at one time, with the blade parallel or near parallel to the product. The cut does not normally occur progressively, with the blade at a large angle to the product. The product and the blade are brought together in parallel and perpendicularly to each other. It is normal for the product to be punch-cut to be fully supported during the cutting process; and that includes both the part of the product that will remain after cutting and also that part of the product that is to be cut away. The familiar hole punch, curiously, operates by means of a shear-cut: the circular opening acting as a counterknife to the punch itself.

On trimming machinery there are two types of blade: plane knife blades and rotary knives. Rotary knives or rotary cutting disks can either have a continuous cutting line, a saw line or several milling cutters.

In his reports Professor Fritsch differentiated between a "knife" and a "clamp". This was of some importance when he came to examine the teaching of Stobb. I deal with this point later.

The experts largely agreed, with minor changes in emphasis, the background knowledge that the skilled addressee would have had. Their evidence was primarily directed to the period between 1985 and 1988; although it was not suggested that the background knowledge would have been different at earlier relevant dates. This background knowledge is relevant for a number of purposes. First, it would colour the way in which the skilled addressee would understand the patents cited as prior art. Second, it would inform the skilled addressee's appreciation of what obvious modifications might be made to the cited prior art. Third, it would colour the way in which the skilled addressee understood the patent in suit itself. The background knowledge included the following:

The experts disagreed on two aspects of the common general knowledge:

I deal with these points later.

The principles of interpretation have been authoritatively expounded by Lord Hoffmann in Kirin-Amgen v. Hoechst Marion Roussel [2005] RPC 9, approving (with slight modifications) the principles described by Jacob LJ in Technip France SA's Patent [2004] RPC 46. In Halliburton Energy Services Inc v. Smith International (North Sea) Ltd [2006] RPC 25, 55 Pumfrey J modified those principles in the light of what Lord Hoffmann had said. In Pumfrey J's revised form they are as follows:

"(a)

The first, overarching principle, is that contained in Art 69 itself. Sometimes I wonder whether people spend more time on the gloss to Art 69, the Protocol, than to the Article itself, even though it is the Article which is the main governing provision.

(b)

Art 69 says that the extent of protection is determined by the terms of the claims. It goes on to say that the description and drawings shall be used to interpret the claims. In short the claims are to be construed in context.

(c)

It follows that the claims are to be construed purposively – the inventor's purpose being ascertained from the description and drawings.

(d)

It further follows that the claims must not be construed as if they stood alone – the drawings and description only being used to resolve any ambiguity. The Protocol expressly eschews such a method of construction but to my mind that would be so without the Protocol. Purpose is vital to the construction of claims.

(e)

When ascertaining the inventor's purpose, it must be remembered that he may have several purposes depending on the level of generality of his invention. Typically, for instance, an inventor may have one, generally more than one, specific embodiment as well as a generalised concept. But there is no presumption that the patentee necessarily intended the widest possible meaning consistent with his purpose be given to the words that he used: purpose and meaning are different.

(f)

Thus purpose is not the be-all and end-all. One is still at the end of the day concerned with the meaning of the language used. Hence the other extreme of the Protocol – a mere guideline – is also ruled out by Art 69 itself. It is the terms of the claims which delineate the patentee's territory.

(g)

It follows that if the patentee has included what is obviously a deliberate limitation in his claims, it must have a meaning. One cannot disregard obviously intentional elements. Hoffmann LJ put it this way in STEP v Empson [1993] RPC at 522:

"The well known principle that patent claims are given a purposive construction does not mean that an integer can be treated as struck out if it does not appear to make any difference to the inventive concept. It may have some other purpose buried in the prior art and even if this is not discernible, the patentee may have had some reason of his own for introducing it."

(h)

It also follows that where a patentee has used a word or phrase which, acontextually, might have a particular meaning (narrow or wide) it does not necessarily have that meaning in context. A good example of this is the Catnic case itself – "vertical" in context did not mean "geometrically vertical", it meant "vertical enough to do the job" (of supporting the upper horizontal plate). The so-called "Protocol questions" (those formulated by Hoffmann J in Improver v Remington [1990] FSR 181 at p.189) are of particular value when considering the difference of meaning between a word or phrase out of context and that word or phrase in context. At that point the first two Protocol questions come into play. But once one focuses on the word in context, the Protocol question approach does not resolve the ultimate question – what does the word or phrase actually mean, when construed purposively? That can only be done on the language used, read in context.

(i)

It further follows that there is no general "doctrine of equivalents." Any student of patent law knows that various legal systems allow for such a concept, but that none of them can agree what it is or should be. Here is not the place to set forth the myriad versions of such a doctrine. For my part I do not think that Art. 69 itself allows for such a concept – it says the extent of protection shall be determined by the terms of the claims. And so far as I can understand, the French and German versions mean the same thing. Nor can I see how the Protocol can create any such doctrine.

(j)

On the other hand purposive construction can lead to the conclusion that a technically trivial or minor difference between an element of a claim and the corresponding element of the alleged infringement nonetheless falls within the meaning of the element when read purposively. This is not because there is a doctrine of equivalents: it is because that is the fair way to read the claim in context.

(k)

Finally purposive construction leads one to eschew what Lord Diplock in Catnic called (at p.243):

"the kind of meticulous verbal analysis which lawyers are too often tempted by their training to indulge."

Pedantry and patents are incompatible. In Catnic the rejected "meticulous verbal analysis" was the argument that because the word "horizontal" was qualified by "substantially" whereas "vertical" was not, the latter must mean "geometrically vertical."'

Ferag wish to make limiting amendments to claim 1. This is permitted, in principle, by section 75 (1) of the Patents Act 1977. MM object to these amendments. The types of objection that I need to deal with at this stage, simply to set the legal framework, are: lack of clarity and additional matter.

Section 14 (5) (b) of the Patents Act 1977 requires that the claim be "clear and concise". So it is a valid ground of objection that the amendment fails to comply with this requirement. The approach of the court to the question whether a claim fails for want of clarity was described by Sachs LJ in General Tire as follows:

"It is clear in our judgment that the question whether the patentee has sufficiently defined the scope of his claims is to be considered in relation to the facts of each case, that allowance is to be made for any difficulties to which the circumstances give rise, and that all that is required of the patentee is to give as clear a definition as the subject matter admits of. It is also clear in our judgment that, while the court is to have regard to all the relevant facts, the issue of definition is to be considered as a practical matter and little weight is to be given to puzzles set out at the edge of the claim which would not as a practical matter cause difficulty to a manufacturer wishing to satisfy himself that he is not infringing the patent. We accept also that definition of the scope of a claim is not necessarily insufficient because cases may arise in which it is difficult to decide whether there has been infringement or not provided the question can be formulated which the court has to answer in deciding the issue of infringement."

Although this case was decided under the Patents Act 1949 I believe that it is common ground that the approach under the 1977 Act is the same. It must, of course, also be borne in mind, when considering allegations of lack of clarity, that the patentee is describing something which, at least in his opinion, is new.

It is another valid ground of objection to an amendment that it would result in the specification disclosing "additional matter": Patents Act 1977 s. 76 (3). In Bonzel v. Intervention Ltd (No 3) [1991] RPC 553, 574 Aldous J said:

"The decision as to whether there was extension of disclosure must be made on a comparison of the two documents read through the eyes of a skilled addressee. The task of the court is threefold: <BR>(1) To ascertain through the eyes of the skilled addressee what is disclosed, both explicitly and implicitly in the application. <BR>(2) To do the same in respect of the patent as granted. <BR>(3) To compare the two disclosures and decide whether any subject matter relevant to the invention has been added whether by deletion or addition. The comparison is strict in the sense that subject matter will be added unless such matter is clearly and unambiguously disclosed in the application either explicitly or implicitly." (Emphasis added)

A patent may only be granted for an invention if it is "new": Patents Act 1977 s. 1 (1) (a). If an invention is not "new" it is said to have been anticipated. There are two requirements for anticipation: disclosure and enablement. Both concepts are explained by Lord Hoffmann in Synthon BV v. SmithKline Beecham plc [2005] UKHL 59. Lord Hoffmann emphasised the importance of keeping both requirements distinct; so I shall describe them (briefly) separately.

Lord Hoffmann summarised the requirement of disclosure as follows:

"[The] matter relied upon as prior art must disclose subject-matter which, if performed, would necessarily result in an infringement of the patent. That may be because the prior art discloses the same invention. In that case there will be no question that performance of the earlier invention would infringe and usually it will be apparent to someone who is aware of both the prior art and the patent that it will do so. But patent infringement does not require that one should be aware that one is infringing: "whether or not a person is working [an] ... invention is an objective fact independent of what he knows or thinks about what he is doing": Merrell Dow Pharmaceuticals Inc v H N Norton & Co Ltd [1996] RPC 76, 90. It follows that, whether or not it would be apparent to anyone at the time, whenever subject-matter described in the prior disclosure is capable of being performed and is such that, if performed, it must result in the patent being infringed, the disclosure condition is satisfied."

Lord Hoffmann went on to summarise the requirement of enablement as follows:

"Enablement means that the ordinary skilled person would have been able to perform the invention which satisfies the requirement of disclosure."

Lord Hoffmann pointed out that in considering whether the requirement of enablement had been satisfied:

"the person skilled in the art is assumed to be willing to make trial and error experiments to get it to work."

A patent may only be granted for an invention if it involves an inventive step: Patents Act 1977 s 1 (1) (b). An invention does not involve an inventive step if it is "obvious to a person skilled in the art": Patents Act 1977 s. 3. An attack on the ground of obviousness must be distinguished from one based on lack of novelty. The classic description of the difference between the two is again that of Sachs LJ in General Tire:

"If, on the other hand, the prior publication contains a direction which is capable of being carried out in a manner which would infringe the patentee's claim, but would be at least as likely to be carried out in a way which would not do so, the patentee's claim will not have been anticipated, although it may fail on the ground of obviousness. To anticipate the patentee's claim the prior publication must contain clear and unmistakeable directions to do what the patentee claims to have invented ... A signpost, however clear, upon the road to the patentee's invention will not suffice. The prior inventor must be clearly shown to have planted his flag at the precise destination before the patentee."

In Synthon Lord Hoffmann added:

"If performance of an invention disclosed by the prior art would not infringe the patent but the prior art would make it obvious to a skilled person how he might make adaptations which resulted in an infringing invention, then the patent may be invalid for lack of an inventive step but not for lack of novelty."

The question whether a step was obvious has been described as a jury question. In Windsurfing International Inc v. Tabor Marine (Great Britain) Ltd [1985] RPC 59, 73 Oliver LJ said:

"There are, we think, four steps which require to be taken in answering the jury question. The first is to identify the inventive concept embodied in the patent in suit. Thereafter, the court has to assume the mantle of the normally skilled but unimaginative addressee in the art at the priority date and to impute to him what was, at that date, common general knowledge in the art in question. The third step is to identify what, if any, differences exist between the matter cited as being "known or used" and the alleged invention. Finally, the court has to ask itself whether, viewed without any knowledge of the alleged invention, those differences constitute steps which would have been obvious to the skilled man or whether they require any degree of invention."

This is now the conventional approach. There are, to be sure, some oddities about the precise framing of these steps: not least that the first step begs the very question that must be answered: Is there an inventive concept at all? Nevertheless, I propose to follow this guidance.

Professor Fritsch described a variety of machines that were in use in the 1980s. Professor Lüthi did not disagree. They were:

Where products were cut in a continuous process, the type of cut used was a shear cut, as with the in-line rotary trimmers.

This patent describes a method for cutting paper products. The printed products enter the machinery in shingle flow. They are aligned; and then pass between two rotary cutters, which cut the head and foot respectively. Each cutter consists of a knife and a counterknife; one of which rotates clockwise and the other anti-clockwise. At the moment of cutting the peripheral speed of the counterknife corresponds to the speed of advance of the shingle flow. The other rotary knife moves much faster. The same process would work equally well with products laid end-to-end or spaced, as opposed to being in shingle flow. Having been cut at both the head and foot, the product moves onto a second conveyor, at right angles to the first, thus exposing the front edge for cutting. The front edge is cut at a second cutting station, again by a rotary knife and counterknife. Although all the pairs of knives and counterknives rotate, they are fixed in position. They move together, rather than independently of one another. This kind of machine requires a "bump turn" between the first and second cutting stations.

The typical layout of this kind of machine looks like this.

Rösner dates from the mid-1970s. It describes a process for trimming paper stacks, principally book blocks, by one or more straight knives while the product is moving. This is achieved by trimming the book blocks by means of a cutting knife as the book blocks are moving, and by then pivoting the book blocks about 90°, again as they are moving, before they are trimmed further by another similar cutting knife. The blocks are held on a trolley or carriage. Rösner describes the cutting knife as follows:

"One advantage is that the knife movement can be chosen at will, anything from a straight-line knife movement in a guide cam to a circular movement if the knife represents the coupling link between the cranks of a parallel crank drive fixed to the frame."

The embodiments show both single knife cutting and also two knife cutting. It is the latter that is relevant for present purposes. As Rösner states:

"The so-called bottom cutting tool which may be a bottom knife for shear-cutting or a cutter board for knife-edge cutting is more effective if fixed to the guiding arrangement although it can be in a fixed position in the machine's cutting station."

In the two-knife cutting, the cutting knife engages the cutting edge of the book block, and a shear cut is achieved against the edge of a counterknife, also associated with the cutting station. As Rösner states:

"It goes without saying that the movement of the knife is synchronised with the movement of the carriage in such a way that the cutting procedure always takes place when the carriage has run into the guiding arrangements and the guiding arrangement briefly moves at the speed of the carriage for the duration of the cutting procedure."

The upper, or cutting, knife moves, guided by a cam, so that it both follows the book block horizontally as it moves through the cutting station, and descends on the book block so as to cut it in cooperation with the lower knife. However, as Professor Lüthi demonstrated, when the cutting process takes place the book block (with the counter-knife attached) moves past the cutting knife, although not all the way past.

The principal debate about Rösner was whether the upper knife was "fixed". I will return to this when I have considered what the patent in suit means.

Stobb dates from the mid-1980s. In Stobb, a trimming station is integrated into a stacker (a "compensated stacker"). Stobb takes three fixed blades arranged in a "U-shape", and the signatures are moved past those blades by means of a rotary motion. Two of the blades are adjustable. One of the striking features of Stobb (which would have struck a skilled engineer in 1985) was that the printed products were conveyed to the cutting station in a rotary manner. This had not been done before, although the rotary conveyance of folded products away from a cutting station, once they had been cut, was known.

The operation of the Stobb process can be seen from Figure 1 of Stobb (partially reproduced).

A conveying means (12) and (13) drops a signature (10) into a clamp, formed by members 18 and 19, pointing vertically upwards, and then rotated anti-clockwise past two fixed side cutters (16) and a fixed front cutter (17) and cut. The figure shows four clamps in a cruciform arrangement. The blades on the side cutters (16) are shown as angled or sloping blades. Once cut, the clamped signature continues to rotate anti-clockwise until the clamp points vertically downwards. The clamp releases the signature, and it falls into the compensated stacker (not shown). The stacker sits on a rotating table, which is rotated periodically by 180^o so that the signatures stack evenly.The patent explains that although the embodiments show the signatures being rotated past the cutters, the cutters could be rotated past the signatures.

Figure 4 explains how the clamp and the side cutters can be adjusted.

"A cross bar 47 is connected at the extending ends of the bars 46, and that determines the spacing between the outer edges 48 of the bars 46 and that spacing is the width of the signature after it is trimmed. When it is desired to change the width of the trimmed signature, then the cross member 47 is changed and a member of a different length can be inserted between the bars 46 and connected thereto, and that will change the spacing between the edges 48 and thus change the width of the signatures to be trimmed, and of course it will be recognised that the side cutters 16 will also be adjusted to have their cutting edges 49 in the plane of the edges 48 for trimming the signature overhang designated 51 in FIG 5."

The final paragraph of the specification in Stobb says:

"It will be seen that the arrangement is such that the holder or clamp member 19 is fixed with the shaft 15 to rotate therewith in the direction of the arrow B, and that rotation is such that member 19 becomes a bed knife relative to the three cutting blades 16 and 17. Thus, the holder 18 is used for pressing the signature against the member 19 which then serves as the main member against which the cutting is accomplished".

Figure 5 shows the side cutters (16) in the plane of the leading and trailing edge of the clamp (46). The clamp is shown as symmetrical. The view is a head on view; and the front of the clamp (corresponding to member 19 in figure 1) is shown as being made of three pieces (46, 47, 46). It is this member that "becomes a bed knife". There was a debate about the meaning of the expression "bed knife". Professor Fritsch said that this reference to a "bed knife" was not a reference to a knife at all; but was really a reference to a cutter board. Member 19, he said, was no more than the side of a clamp and could not be regarded as a counterknife to the cutting blades. He pointed to many instances in the specification in which the relevant members were described as parts of a clamp; and contrasted this with the single mention of a bed knife. He produced what he said was an "example" of use of the phrase "bed knife" to mean a cutting strip. But the "example" turned out to be the only discovered use of the phrase in that sense; and even then, the drawing that accompanied the text cast doubt on whether the phrase was used in the sense that Professor Fritsch contended. Professor Fritsch was shown other usages of the phrase "bed knife" which did not conform to his interpretation. I did not find this part of his evidence convincing, and to be fair, Professor Fritsch did not adhere fully in his oral evidence to the view he had expressed in his report. There is no reason why a member cannot be both a clamp and a counterknife. The real debate was whether Stobb disclosed a counterknife. I will return to this question when I have considered the meaning of the patent in suit.

The description has a conventional structure, with the nature of the problem addressed by the patent being identified by reference to the prior art. The specification begins by explaining that existing methods of trimming multilayer printed products use a planar conveyor belt to move the scale flow against one or more rotating cutting knives, which cut the products. These methods are said to produce acceptable cutting results but to suffer from the disadvantages that:

The patent goes on to explain that the patentee has already proposed a solution which avoids scalar flow and in which the printed products are conveyed in a rotating cell or bucket wheel in which the individual cells are provided with movable knives operated by cams to carry out a shear cutting operation : CH 583 611 (Reist 1975). However, this is said to be complicated and costly to maintain. The specification continues on page 2 (lines 18-27) to say that high performance (i.e. high speed) processes do not achieve the same cutting quality as static or alternating processes in which entire paper stacks can be cut by a carefully guided swinging or dropping knife.

It is said at page 2 lines 29-30 that the aim of the Patent is to overcome "this problem" However, as Mr Floyd QC pointed out, at least four problems have in fact been discussed up to this point:

There is then a further statement of a problem set on the basis of CH 583611. This involves achieving "a reliable and accurate method and a simple, maintenance-friendly and inexpensive apparatus, with which a high-quality cutting of multilayer printed products in a continuous process and in particular in a high-performance production process". This is said to be solved by the characterising features of the independent claims (i.e. claims 1 and 9). The specification then goes on to describe conventional cutting processes as follows:

"In conventional cutting processes … either the printed products are supplied continuously or individually to a cutting mechanism, in which the knife and counterknife are fixed, or there are a plurality of cutting mechanisms at least temporarily moving with the printed product and also comprising a knife and counterknife. These known cutting mechanisms, no matter whether they are fixed or moved together, consequently always comprise substantially two parts, namely a knife and a counterknife, which are associated with one another pairwise and in a fixed manner".

The invention is said to take:

"a new route in that it breaks with the conventional knife-counterknife unit and the two knife parts are positioned and moved independently of one another, one knife part being fixed relative to the material being cut and is only temporarily brought into a clearly defined cutting engagement".

The advantages of the invention are described as:

The principle of the method is shown in Figures 1a and 1b. Figure 1a is a side view (i.e. in elevation form). Figure 1a shows the method in elevation; and figure 1b shows it in plan.

A scale flow of printed products (2) is broken up into individual products or groups of products (the figure shows groups of three). Each group is associated with a first knife part (3) which is "concomitantly moving with the printed products" (Phase II). The products are oriented along an edge (4) and engaged in Phase III. In Phase IV the printed products and associated knife part are moved past a second knife part (5), shown in the figures as a rotary knife. As Professor Fritsch explained, the product has to be orientated in Phase III in order for the cut to take place. In practice orientation is achieved by clamping. The cut takes place as the two knives pass each other in Phase IV.

The use of a rotary knife as the second knife is only an example. The specification says:

"It obviously falls within the scope of the invention to give a different shape and function to the second knife part. Thus the second knife part can e.g. be constructed as a stationary, non-rotating blade or as a movable, non-fixed knife part."

"obviouslyfurther cutting mechanisms (e.g. rotating wires) are possible with which the lateral edges of the moved past printed products can be cut in conventional manner".

The patent itself proposes three different kinds of knife for the second knife part: a cutting roller; rotating wires and other geometrical shapes e.g. conical and frustrum shaped rollers.

Figure 2 is the first preferred embodiment described. It describes apparatus for three-sided cutting or trimming.

The drum rotor (11) has cells (12) for receiving a scalar flow of printed products in the direction of arrow "A".

Cutting is achieved because the mechanisms (14) and (15) are designed to engage with the adjacent edges of cell walls (31) which are constructed as counterknives. This could be done either by constructing the whole cell as a counterknife or, more probably, by incorporating a knife in the appropriate place in the cell wall. A close-up of how the knife (14) engages with the product in the cell against the cell wall (31) "which simultaneously acts as a counterknife" as the drum rotates is shown in Figure 11 and described in the specification itself.

Having passed through cutting points (14) and (15) where the head and foot are cut, the printed product moves on to cutting point (16) where the front is cut. The printed product must now be realigned and re-orientated so that the front edge can be cut. This is done by opening the clamp and then closing it again. The figure shows the printed product moving towards the outer circumference of the cell as soon as it has been cut by cutter (15). In the figures in the patent, the head and foot cut take place before the front cut; but there is no technical reason why they should not take place in reverse order. It is, however, necessary for there to be sufficient distance between the head and foot cuts on the one hand, and the front cut on the other to allow time for the realignment of the printed product to take place.

The patent contains its own explanation of what is meant by "fixed". It says:

"The term "fixed" used hereinbefore in conjunction with cutting knives and rollers naturally does not exclude the possibility of the cutting mechanism being adjustable with respect to the drum rotor, as a function of the printed product and the desired cut. It in fact means that there is no change to the position of the cutting mechanisms during operation."

The patent claims both a process and a product. It is the process claims that are the relevant ones. Claim 1 is in the following terms:

"Method of cutting or trimming continuously conveyed, multilayer printed products (2) in a continuous process, in which at least one first knife part (3, 31) is jointly associated with each one or several printed products (2), in which at least one first knife part (3, 31) and the associated printed product (2) are moved at substantially the same velocity and are engaged with one another along at least one cutting edge (4), characterized in that the first knife part and the associated printing product are moved past a second, fixed knife part (5, 14, 15, 16, 18, 19) in order to be brought into cutting engagement therewith, so that the printed product is at least cut along an intended cutting edge."

However, Ferag have applied to amend the claim so that it will read (without the numbers):

"Method of cutting or trimming continuously conveyed, multilayer printed products in a continuous process, in which at least one first knife part is jointly associated with each one or several printed products, in which at least one first knife part and the associated printed product are moved at substantially the same velocity and are engaged with one another along at least one cutting edge, characterized in that a first knife part for each of the front edge and back edge cuts and the associated printed product are moved past a second, fixed knife part for each of the front edge and back edge cuts, and that a first knife part for the top edge cut and the associated printed product are moved past a second, fixed knife part for the top edge cut, which second, fixed knife part for the top edge cut is displaced [in the conveying direction] from the second, fixed knife parts for the front edge and back edge cuts, in order to be brought into cutting engagement therewith, so that the printed product is cut along each intended cutting edge."

As I have said, MM object to the amendment on a number of grounds, which I will come to in due course. For reasons that I will explain I have put the words "in the conveying direction" in square brackets.

Claim 2 claims:

"Method according to claim 1, characterised in that a plurality of first knife parts (31) is moved at regular intervals on a clearly defined path, whilst the second knife parts are left stationary."

Claim 3 claims:

"Method according to one of the preceding claims, characterised in that the printed products (2) by the at least one first knife part (3, 31) associated therewith are moved past at least one second knife part."

It is agreed that claim 3 has suffered somewhat in translation; and that it is better read as if it said:

"Method according to one of the preceding claims, characterised in that the printed products (2) are moved by the at least one first knife part (3, 31) associated therewith past at least one second knife part."

Claim 4 claims:

"Method according to one of the preceding claims, characterised in that at least one first and at least one second knife part are so brought into cutting engagement that the printed products are continuously cut from one end of the intended cutting edge to the other."

The experts agreed that a knife must be both hard and sharp. This applies to both a cutting knife and a counterknife. The patent teaches that the cell walls (31) are either provided with counterknives "or are themselves constructed as counterknives". Plainly, therefore, a counterknife may be dual (or multi) functional. In the embodiment the cell wall (of which the counterknife is part) also functions both as the means of propulsion of the printed product, and also as one side of the clamp that aligns the product, and holds it in position.

The disputed phrase is the requirement that the first knife part (i.e. the cell wall or part of the cell wall acting as a counterknife) must "be jointly associated with each one or several printed products." The grammar is not entirely easy to follow; but the sense of it is that each first knife part is associated with either one product or with several products. The embodiment in figure 1 shows groups of three products, each group being associated with the same cell wall. The real dispute is whether the association must be a physical association.

Mr Mellor submits that the requirement of association simply means that at the time of cutting there is a first knife part allocated to the one or several printed products in question. This integer is satisfied if each individual printed product or each group of printed products has allocated to it its own first knife part. In the course of his oral opening he explained that as long as you can predict which of the counterknives is going to cut which of the products, the requirement of association is satisfied. He confirmed in his closing address that this was the interpretation that he advocated.

I do not accept this interpretation. If it were correct, it would apply to every trimmer; since it is always predictable which knife part is going to cut which product. In in-line rotary trimming, for example, with two rotary knives, one each side of a scale-flow, it is predictable that one of the knives will cut all the heads and the other will cut all the feet. In Stobb it is predictable that the side cutters will cut all the sides and the front cutter will cut all the fronts. The requirement of association in the patent in suit must mean more than that.

The description of the process in the specification says that during Phase II the first knife part is "concomitantly moving" with the printed products. This is the phase in which the knife part "catches up" with the printed products. In Phase III (i.e. before cutting) the printed products and the first knife part "are … engaged". The use of the word "engaged" must mean (at least) that the first knife part and the nearest of the printed products are touching. Indeed the products must be clamped in the cell before being cut. In Phase IV both the printed product and the first knife part "are moved" past the second knife. The use of the passive voice both here and in claim 1 suggests that they move together, rather than independently. The basic idea behind the invention is that the two knife parts move independently of each other, and that the first knife part is "fixed relative to the material being cut"; and that the cutting engagement is temporary. This is in contrast to known machines, where the knife parts move temporarily with the printed product, but where they are fixed relative to each other. It is in my judgment clear that the word "associated" requires a physical association; and not merely predictability.

The second area of dispute was whether the association must last longer than the mere moment of cutting. In my judgment it must. One of the purposes of the cell is to hold the printed products in a clamp. The product must be aligned before cutting and then re-aligned (still in the cell wall) before the final cut. The patent teaches that the first knife part must be "fixed relative to the material being cut" which itself suggests that the association is more than merely momentary. It contrasts this with the cutting engagement, which is only temporary. In addition the claim requires that the first knife part and the printed product "are moved at substantially the same velocity and are engaged with one another along at least one cutting edge". This is clearly a reference to Phase III, since it precedes the movement past the second knife. The requirement that the velocity of the knife part and the printed products be the same means that they must be moving at the same speed and in the same direction. The claim goes on to require that the first knife part and the associated product are "moved past" a second knife. Thus the physical association (same speed and direction) lasts from at least Phase III until the product has gone past the second knife, which is necessarily after it has been cut.

The claim requires the first knife part and its associated printed product to be "moved past a second … knife in order to be brought into cutting engagement therewith". This integer, as it seems to me, requires both a movement ("past" the second knife) and a purpose of the movement ("in order to be brought into cutting engagement" with it). If the movement occurs for other reasons, then this integer is not satisfied. I consider also that since the cell wall trails the printed product, the movement of the printed product must be all the way past the second knife, in order for the cutting engagement to take place. This is shown clearly in the final stage of Phase IV.

This is the requirement that the first knife part and its associated printed products are moved past "a second, fixed knife part". The explanation in the specification of the use of the word "fixed" is that it means "that there is no change to the position of the cutting mechanisms during operation". Mr Mellor submits that the important point is that the position of the cutting mechanisms does not change during operation. This, he says, means that the cutting mechanisms must be fixed in the conveying path of the printed products rather than, for example, swinging into and out of the conveying path. In my judgment, it all depends on what you mean by "cutting mechanisms".

The blade itself could be a fixed blade, but this is not required by the patent. The embodiments themselves describe a rotary knife, in which the cutting edge rotates. Plainly the blade of the second knife part must be allowed to move, otherwise it would not effect a cut. The specification itself says that:

"… the second knife part can e.g. be constructed as a stationary, non-rotating blade or as a movable, non-fixed knife part."

The "cutting mechanisms" must, therefore, mean more than just the blades. How much more? In my judgment the phrase refers to the knife, taken as a whole. I do not consider that the phrase excludes an oscillating knife which oscillates between fixed points. Professor Lüthi produced a drawing of an oscillating knife, mounted on a parallelogram which, he said, would work as well as the rotary knife shown in the embodiments. Professor Fritsch thought that a knife of this kind would suffer excessive wear, but otherwise agreed that it would work. The essential point of departure that the patent claims is that one knife travels with the printed product, while the other stays where it is. Since the claim is a method claim, and the method claim works equally well (from a technical, cutting, point of view) with an oscillating knife, there is no reason for excluding such a knife from the meaning of "fixed", as that word is used in the context of the patent in suit. I cannot see that it makes any difference whether the blade goes round and round or from side to side. In either case the cutting mechanism as a whole will remain fixed. The fact that the method works just as well with an oscillating knife means, in my judgment, that Professor Fritsch is wrong to suggest that the reference in the specification to a "movable non-fixed knife part" is simply a draftsman's error. There is no irreconcilable internal inconsistency in the patent. The knife part (i.e. the blade) may be non-fixed. It is the cutting mechanism, taken as a whole, that must be fixed.

The dispute here is whether the requirement is that the printed product must be cut along the whole of its length, or whether a cut may stop short of the edge of the printed product.

Mr Floyd submits that the "intended cutting edge" is no more than the edge along which it is intended to cut. If it is intended to cut along the whole of the (uncut) edge of the product, then that is the intended cutting edge. But if it is intended to cut only half way along the (uncut) edge, then that is the intended cutting edge. Mr Floyd also drew attention to claim 18 (an apparatus claim) in which it is claimed that the apparatus is so constructed that "the edges of the printed products are cut from one end to the other". This, he says, shows that the patentee knew how to describe a cut along the whole length of the (uncut) printed product. He had not done so in claim 1.

Mr Mellor, on the other hand, points to the embodiments of the method. The figures consistently show that the printed product is cut along the whole of its (uncut) edge. Moreover, it is clear that the patent is concerned with two-knife cutting: its whole point is the separation of knife and counterknife. In any two-knife cut the line of engagement of the two knives must extend beyond either side of the product to be cut. This is a general principle of two-knife cutting. Consequently the skilled addressee, reading the patent in context would understand the expression "intended cutting edge" to mean the whole edge of the (uncut) product.

I do not consider that claim 4 sheds any light on this debate. It is true that it refers to cutting from "one end" to "the other". But from one end of what? From one end "of the intended cutting edge" to the other. So the precise meaning of the intended cutting edge is still at large. All that you can say about it is that it has two ends. So I put claim 4 on one side.

Although I see the linguistic force of Mr Floyd's submission, I consider that it places insufficient weight on the context of the patent; and the common general knowledge that the skilled addressee would bring to bear on his reading of it. The argument is the same sort of argument that the House of Lords rejected in Catnic ("vertical" contrasted with "substantially horizontal"). The skilled addressee would know that the trimming of products is typically performed by arranging trimming knives so that cutting occurs progressively from one edge of the paper to the other. This was common ground between the experts. So if the product was not to be cut from end to end the skilled addressee would, I think, have expected to be told that in terms. He would also notice from the description of the preferred embodiment that as the process unfolds "the observer-facing lateral edge of the printed product is trimmed"; and that the final cut is that of "the top edge of the printed product". He would also know that if the printed product was not cut along the whole of its (uncut) edge, there would be waste still partially attached to the partially trimmed product, with no clear means of disposing of it. Read in context, I conclude that the intended cutting edge means the whole length of the uncut product.

That part of the amendment to which MM objects is the part that introduces the requirement that the second fixed knife part for the front cut "is displaced in the conveying direction" from the second fixed knife part for each of the head and foot cuts.

The first ground of objection is that the amendment, read in conjunction with the specification, is unclear. This submission is based on the point that the phrase "displaced in the conveying direction" naturally means that the top edge cut takes place downstream of the head and foot cuts; yet the specification says in terms that the cuts can be performed in the order either front, followed by head/foot; or head/foot followed by front. There is, in my judgment, considerable force in this point. However, in the course of his closing address, Mr Mellor abandoned the phrase "in the conveying direction"; so that the amended claim simply requires the second fixed knife for the front cut to be "displaced" from the second fixed knife for the head and foot cuts. It is obvious from the context that the displacement must be in the line of flow of the continuously moving products, either upstream or downstream. In my judgment this amendment to the amendment removes this ground of objection.

The second ground of objection is that the notion of "displacement" is itself unclear. First, Mr Floyd submitted that it was not clear whether the displacement was in time or in space. In a case in which (as I have held) the cutting is required along the whole of the edge of the uncut product, I would have thought that displacement in space necessarily implied displacement in time; and vice versa. Otherwise there is a potential conflict between blades. Second, Mr Floyd pointed out that the second knife parts in the patent all cut progressively, from one end to the other. In such a case, if a cellular-type machine such as is disclosed in the patent is used, each second knife will start cutting at one point in the rotation and finish cutting at a different point: say from 12 o'clock anti-clockwise through to 10 o'clock. If the next second knife cuts from 11 o'clock to 9 o'clock, so there is an overlap in the cuts, is it "displaced" as required by claim 1? Mr Floyd submits that conflicting answers could be given to that question. The word "displaced" is nowhere used in the unamended patent, so that there is no previous context to which to appeal. Since the claim must be construed at the level of generality at which the invention is claimed, it is incorrect to restrict the meaning of "displaced" by reference to the specific embodiments. Mr Mellor submitted that in context, the word "displaced" meant "separate". The skilled addressee, as a practical person, would not read this as being satisfied by an infinitesimal separation but would see it as requiring a real separation. This precludes overlapping cutting stations. The ordinary meaning of "displace" is, at least to my understanding, to move something from a place. A "displaced person" is one who has been compelled by some external pressure to leave his home. That is clearly not what it means in the amendment. All it means in the patent is that the second fixed knife for the front cut is not in the same place as the second fixed knife for the head and foot cuts. I do not regard the meaning of "displaced" as necessarily conveying the meaning that the two cutting stations must have no overlap. In cross-examination Professor Fritsch accepted that some degree of overlap was technically possible. But I agree with Mr Mellor that the suggested difficulties are "puzzles at the edge of the claim". In my judgment this amendment does not fail for want of clarity.

The third ground of objection is that the amendment is what in the jargon of patent lawyers is called "an intermediate generalisation". Pumfrey J explained this concept in Re Palmaz's European Patents [1999] RPC 47, 70 as follows:

"If the specification discloses distinct sub-classes of the overall inventive concept, then it should be possible to amend down to one or other of those sub-classes, whether or not they are presented as inventively distinct in the specification before amendment. The difficulty comes when it is sought to take features which are only disclosed in a particular context and which are not disclosed as having any inventive significance and introduce them into the claim deprived of that context. This is a process sometimes called "intermediate generalisation"."

Mr Floyd submits that the feature of displacement is nowhere explained in the context of the general method claimed in claim 1. Figures 1a and 1b and the discussion of the method from page 5 line 1 to page 6 line 5 of the patent is the only description of the general method. There is no displacement of front from head and foot there. Displacement is only shown in relation to the preferred embodiment discussed from page 6 line 11. What the patentee is trying to do is to lift a feature only shown in relation to this embodiment and to teach it as having general significance shorn of its earlier context. Yet it has no general application. The only utility of the feature which has been identified is in relation to certain specific constructions where you are aligning between cuts. But the claim is not limited to such constructions. The general significance of displacement is not taught; and no technical significance is given to it. Mr Floyd accepts that it would be possible, without infringing the prohibition on intermediate generalisations, to amend the claim so as to include a method step of realigning the printed product, and giving time for that realignment to take place. But that is not what Ferag seeks to do.

Mr Mellor's first riposte to this objection was that it was not pleaded. I disagree. The first pleaded ground of objection was that the proposed amendment "generalises the use of a sequential cutting process by disclosing it without limitation to the context of the cellular construction." The point was, moreover, put in paragraphs 53 and 54 of MM's opening skeleton argument; and Professor Fritsch was cross-examined on the subject of permissible separation without objection. I do, however, accept that the point as Mr Floyd developed it in his closing address had changed its focus. But since this a question of interpretation of the patent, I do not see that this is fatal. Mr Mellor's second riposte was that since the patent required the cut to take place along the whole of the (uncut) edge of the printed product, some separation was necessarily implicit because of the risk of conflicting blades. There was, therefore, implicit disclosure of the different locations of the cutting mechanisms. Implicit disclosure is good enough. If (as I think) the word "displaced" is given the more limited meaning I have ascribed to it, I consider that Mr Mellor's second point is a good one.

I would not have refused to allow the amended amendments on the grounds argued before me.

The final ground of objection was based on discretion. This ground raised questions of fact; and both parties agreed that consideration of this ground should be deferred (if it still arises).

Mr Mellor submitted that there were four essential reasons why the clamp could not be regarded as a counterknife:

It is clear from the specification that the edges of the clamp (48) must be in the same plane as the cutting edges of the side cutters (16). This is why the specification says that the top part of the clamp (member 19) becomes a bed knife. The description of that member as the member "against which" the cutting is accomplished reinforces this. Mr Mellor submitted that the reason why member (19) became a bed-knife was because of its rotation, which in accordance with the principles of visco-elasticity, means that the combination of the speed of the rotation and the inertia of the paper product creates a stiffness in the paper product that allows the cutting to be effected by a single knife. However, I do not consider that a knowledge of the principles of visco-elasticity would have been part of the mental toolbox of the skilled addressee of the patent at the time. The principle had not previously been used in trimming machinery. A learned paper had been read about the subject at a conference in Switzerland, and one or two companies were investigating it. It is also doubtful whether the cruciform arrangement of the clamps could be fed and rotated fast enough to produce this effect. In my judgment Mr Mellor's construction of this part of the specification is over-sophisticated and should be rejected.

The edge of the clamp and the blade of the cutters are in cutting engagement, even though it is only the cutters that slice through the printed product. The edge of the clamp and the blade of the cutters pass by each other as the cut takes place. Professor Fritsch accepted that the bars would have a "very decisive and important part to play in the cutting process". The use of the shear cut was the normal type of cut used in continuous trimming (which Stobb was). The arrangement of the cutting blades also showed that the cuts were progressively made, which is one of the characteristics of a shear cut. The skilled addressee would also notice that the product to be cut was not fully supported; and this, too, would point away from a punch cut. Professor Lüthi said that the trailing edges of the clamp functioned as counter-knives in the cutting process. Accordingly, he said, they were counter-knives. Moreover, member 18 is described as "pressing" the signature against member 19 which is the way one would expect a pressing block and counterknife to work. The strongest point in favour of the conclusion that the edge of the clamp was not a knife is the fact that, as shown in the figures, the leading edge is made of three parts, screwed together. Both experts agreed that a knife (or at least a straight knife) must be made of a single part.

In my judgment Professor Lüthi had the answer to this point. He said that Stobb was not a blueprint for the manufacture of a working machine. It was a schematic presentation. A skilled addressee would construct member (19) as a counterknife and would realise that there needed to be marginal clearance between the leading edge and the trailing edge of the clamp. The kind of clearance required would be no more than a few microns. The details were not difficult to achieve. The edges of member (19) could be mitred corners, which any skilled person would adopt in constructing a working model of Stobb. To build in a measure of clearance was straightforward engineering. They do not fall outside the scope of trial and error experiments to make the machine work. I accept Professor Lüthi's view ("if it moves like a duck, and quacks like a duck …"). For practical purposes member 19 is a counterknife in a two-knife shear cut. In my judgment Stobb discloses a counterknife (or, in the language of the claim a "first knife part").

Stobb cuts all three edges of the printed product almost simultaneously, leaving a U-shaped waste. It does not cut along the whole of any of the edges of the uncut product. It does not, therefore, disclose this integer of the claim as I have interpreted it.

As I have said, Stobb cuts all three edges of the printed product almost simultaneously. "Almost" is important. In fact although the operation of Stobb is very fast, in Stobb the front is cut first and then the head and foot. The front knife is "displaced" from the side knives because all but an infinitesimal cutting of the sides happens after the front knife has finished cutting. Stobb discloses this integer of the claim as I have interpreted it.

However, Stobb does not disclose all the integers of the claim. Accordingly, in my judgment Stobb does not anticipate.

The answer to this question depends on the meaning of "fixed" in the patent in suit. It is common ground that the top knife shown in Rösner is a reciprocating knife. It is guided by a cam, so that it both follows the book block horizontally as it moves through the cutting station, and descends on the book block so as to cut it in cooperation with the lower knife. However, although the path of the blade is mobile, the top knife, taken as a whole, remains fixed (in the sense in which, in my judgment, the patent in suit uses that word). Rösner therefore discloses this integer.

As I have said, Professor Lüthi demonstrated that the book block and the lower knife moved part of the way past the upper knife. They did not move the whole of the way past. Rather the blade of the upper knife retracted, and then the book block moved on. In addition, the movement of the book block and the lower knife was the conveying process, rather than part of the cutting process itself. In other words the movement did not take place "in order" to bring the two knives into cutting engagement. In my judgment Rösner did not disclose this integer.

Rösner does not, therefore, disclose all the integers of the claim. Accordingly, in my judgment Rösner does not anticipate.

It is not suggested that the invention described in the patent in suit is obvious in the light of (or, as patent lawyers prefer, "over") Rösner. The attack is based on obviousness in the light of Stobb. In this section of my judgment I assume that Stobb does not disclose a counterknife.

MM submit that the inventive concept of claim 1 is arranging for a printed product to be continuously engaged, associated and conveyed with a first travelling knife past a second fixed knife so as to come into cutting engagement with and perform a shear cut on the printed product. Professor Lüthi said:

"The basic inventive concept underlying the Patent is the use of a counterknife that moves with the signature to be trimmed throughout the cutting process."

Rather more bluntly, Mr Floyd said that the inventive concept of claim 1 was "Stobb with knives".

Mr Mellor was surprisingly diffident about identifying the inventive concept embodied in the patent, beyond saying that it was all in the claim. In some cases it may be possible simply to say that it does what it says on the tin; but I would have been helped by Mr Mellor's description in ordinary English of what Ferag say they have invented. Professor Fritsch described the invention in his first report as follows:

"Because the first knife travels with the product, it is moving independently from the second fixed knife. This is different from the other known mechanisms – in each of them, where there are two knives per cutting station, those knives are associated with each other pairwise and in a fixed manner."

Professor Fritsch also drew attention to the features that:

The first of these features is present in Stobb. Moreover, Professor Lüthi said that the transport of signatures perpendicular to the printed surface had been common for many years. It was "a standard arrangement" and was within the common general knowledge of the skilled addressee. He produced a photograph of a machine made in 1969 which transported books in this fashion. Since the machine was illustrated in a standard text book called "The Bookbinder's Handbook" it was surprising that Professor Fritsch had never heard of it. I accept Professor Lüthi's evidence. Machines for converting scalar flow into a rotating paddle wheel arrangement were also known in the newspaper industry. I accept Professor Lüthi's evidence that the skilled addressee would have known this too. The second feature to which Professor Fritsch drew attention is also present in Stobb. The third is not; but it was commonplace in in-line rotary trimming for the head and foot cuts to take place at different points in the conveying process.

In my judgment the heart of the invention (and hence the inventive concept) is the separation of knife and counterknife: the one travelling with the printed product (but fixed relative to the printed product) and the other remaining fixed (in the sense I have described). This means that there can be many counterknives per knife (i.e. the knife and counterknife are not associated with each other "pairwise"). Of equal importance is the feature of the counterknife that it is (or is part of) the cell wall, and therefore also acts as a part of the clamp. The invention is limited to cutting products from end to end.

This is the same body of knowledge as is attributed to the skilled addressee for the purpose of interpreting the patent. I have already described this.

There are three potential differences between Stobb and the patent. The first is that (if I am wrong about my interpretation of Stobb) it does not disclose a counterknife. The second is that Stobb does not cut along the whole length of the (uncut) printed product. The third is whether (if I am wrong about my interpretation of the patent in suit) the cutting stations in Stobb are displaced from one another.

I have already described (and accepted) Professor Lüthi's evidence about the features that a skilled addressee would build into Stobb in carrying out the process of implementation. These included the mitring of the corners of the trailing member of the clamp (so as to make it a more conventional knife part made from a single piece) and the leaving of a few microns clearance so that the cutting knives did not foul the leading edge of the clamp. He considered (and I agree) that these were inherent in the disclosure itself. But if I am wrong about that, then it seems to me that these are obvious and uninventive modifications. The explicit reference in Stobb to the clamp becoming a bed knife is a clear signpost along the way. If these members are constructed as counterknives then there is a separation of knife and counterknife (the counterknife travelling with the signatures); and there can be many counterknives per knife (the cruciform arrangement shows four).

The second difference is that Stobb does not cut along the whole of the printed product, but leaves a U-shaped waste. If it were desired to cut the whole length of the printed product this would be possible using two Stobb machines in sequence; the first carrying out the head and foot cuts and the second carrying out the front cut (or vice versa). Professor Fritsch agreed that there was nothing new in using machines in sequence like this (the idea had been around for twenty years); but he thought that it would be uneconomic to do so. Mr Mellor relied heavily on the fact that Professor Lüthi did not list the use of two Stobb machines among the modifications that he would have made. But this omission is easily explained. Professor Lüthi was working on the basis that the patent in suit did not require cutting along the whole of the length of the (uncut) printed product. So on his interpretation of the patent (which I have disagreed with) there was no need to use machines in series. In my judgment Professor Fritsch's evidence in cross-examination is an adequate foundation for the conclusion that if it were desired to cut along the whole length of the (uncut) printed product, it would have been obvious to use two Stobb machines in series.

The use of two Stobb machines in series also means that the two cutting stations are displaced from one another. There is also another answer to the question of displacement. Both experts agreed that it would have been obvious to the skilled addressee to change the shape of the cutting blades. Their preferred change was to make the front cutting blade (17) in the shape of an inverted V (although Professor Lüthi considered other configurations as well). The blade would have to be a curved helical blade in order to follow the curve of the drum. But both experts agreed that helical blades were well known and that a skilled addressee would know about them. The effect of redesigning the blade in this way would be that the cut would start in the middle of the paper with front cut knife 17, with the cut progressing in two opposite directions towards the corners of the paper. Both head and foot knives 16 and 16 then cut simultaneously from the outside to the inside. The shape of the blades is reproduced below.

Professor Fritsch criticised the means of conveying signatures into the cruciform arrangement of clamps. His criticism was that it would not feed the clamps fast enough for the visco-elastic principle to work. But if (contrary to his view) Stobb operated by means of a shear-cut, then he accepted that the conveying means would work. In addition, Professor Lüthi also said that the use of a drum for conveying the signatures was "an attractive but obvious arrangement". I accept Professor Lüthi's evidence. A change of the conveying-in means would, in my judgment, have been an obvious modification.

In his cross-examination of Professor Lüthi, Mr Mellor took him through a series of changes that the Professor said would be made to Stobb. Some of the changes (for example the discarding of the rotatable stacker) are irrelevant to the inventive concept claimed by the patent in suit. Others (for example the strengthening of the clamp) are merely workshop variations. Some were simply different ways of putting the same point. Yet others (changing the design of the blades) were agreed by both experts to be obvious. Although Mr Mellor built up a list of changes that looked impressive at first sight, it must be remembered that the test of obviousness is qualitative rather than quantitative. Whether looked at singly or cumulatively, I do not consider that any of the changes required invention.

I conclude that the invention described in the patent in suit is obvious in the light of Stobb.

The following description is taken from the product and process description. A conveyor rotates around an axis in an anti-clockwise direction. The angular speed of the conveyor is steady. Each printed product is held between a pair of leading and trailing clamp pieces. The products move as the conveyor rotates. Each leading clamp piece is attached by a spring to a point inward and ahead of it on the conveyor. Accordingly, when the leading clamp piece follower rolls are free the printed products are clamped between each leading clamp piece and its corresponding trailing clamp piece. Each pair of leading and trailing clamp pieces is pivotally journalled on a pivoting bolt. The centres of these bolts are disposed at a constant radial distance from the centre of the conveyor and are equally spaced at intervals of 20°. Each trailing clamp piece has a follower roll at the end of a lever arm. The rolls are constrained by cam surfaces, which together comprise a guide track. This causes the leading and trailing clamp pieces (and the printed products held between them) to rotate into different angular positions with respect to their respective radial directions as the conveyor rotates.

The trimmer comprises six rotating knife parts which are disposed on a circumference at equal 60 ⁰ spacings. The rotating knife parts of the trimmer rotate clockwise about an axis. Each printed product makes contact with a rotating knife part at about 10 o'clock. The trimmer includes a single fixed knife part. The inner edge of the rotating knife part passes the fixed knife part at approximately 11 o'clock at which position the printed product is trimmed at its end by being cut between the two knife parts. The drawing in the PPD is partially reproduced below.

Thus if we follow the progress of a printed product, it is shown clamped in position 1. The clamp moves anti-clockwise through positions 5 and 9. Meanwhile the rotary counterknife is rotating clockwise. The fixed rotary knife is rotating anti-clockwise. The counterknife and the printed product come into contact just before position 13; and the cut takes place between positions 13 and 14. The speed of the rotating counterknives is constant. However, the speed of the printed product varies during this process. Between positions 1 and 10 it moves quickly. The purpose of this is to allow the printed products to fan out so that they can be placed more easily between the rotating knife parts. Then the printed products are slowed down suddenly, so that by the time of the cut itself they are moving at the same (or almost the same) speed as the rotating counterknives.

A pair of side trimmers are placed at a different position on the circumference of the conveyor, usually upstream. One trimmer is in front of the drawing, the other behind it. As each printed product passes the side trimmers it is caused to move to the positions 1 to 17 as shown on the drawing. The side trimmers have their axes parallel to the plane of the drawing and to a radius corresponding to position l3 of the printed product, and so perpendicular to the axis of the conveyor. The distance between the fixed knives on the two side cutters is equal to the width of the product after trimming.

The essential difference between NewsTrim and the patent in suit is that in NewsTrim the counterknife does not travel with the printed product. The printed product is conveyed by a separate clamp. Of course the counterknife makes contact with the printed product at the time of the cut; otherwise the cut could not take place.

The issue on infringement relates to the following words of claim 1:

"…at least one first knife part is jointly associated with each one or several printed products, in which at least one first knife part and the associated printed product are moved at substantially the same velocity".

In the light of the meaning that I have attributed to "jointly associated", the counterknife in NewsTrim is not jointly associated with the printed product.

It is common ground that at the exact moment of cutting the counterknife and the printed product are moving at substantially the same velocity (i.e. at the same speed and in the same direction). As Professor Lüthi puts it:

"Of course it is inevitable that if a cut is to be performed at all, at the very moment of cutting the first knife part and the part of the product being cut must move at the same velocity and be engaged."

However, up to that point they are not moving at substantially the same velocity. This can be seen most easily by comparing the position of the counterknife along the length of the printed product. Professor Lüthi carried out rather more sophisticated calculations which showed the same thing. The printed product is located between two counterknives at position 11. The trailing counterknife "catches up" with the printed product at position 12. From then on until the cut at position 13 they move at substantially the same speed. But between position 12 and position 13 the counterknife has moved further from the uncut edge of the printed product, so that they are not travelling in the same direction. Thus they are not travelling at the same velocity. At position 13 the printed product and the counterknife are moving at the same velocity for an instant of time, necessary to perform a cut. Immediately afterwards their directions of travel diverge. When dealing with the meaning of the word "displacement" in the patent in suit Mr Mellor argued forcefully that the skilled practical person would not be concerned with "infinitesimal" displacement. I think that the same approach is warranted when considering whether the counterknife and printed product in the NewsTrim machine are moving at the same velocity. The practical person would not be concerned only with the precise instant at which the cut takes place. If one lifts one's eyes from the exact moment of cutting, the counterknife and the printed product do not move at the same velocity.

In addition, I agree with MM that the two rotating knife parts of the NewsTrim machine are fixed (in the sense that they remain in the same overall location during the trimming process) and are associated with each other as a pair (in pairwise manner). Thus, in my judgment, they more closely fit the patent's description of conventional cutting machines than the new route that the patent claims.

I conclude that NewsTrim does not infringe.

I conclude that claim 1 of the patent (whether in its unamended or amended form) is invalid for obviousness; but, if valid, it is not infringed. I believe that my decision on the invalidity of claim 1 means that dependent claims 2, 3, 4 and independent claim 9 are also invalid. The precise permutations were not explored in detail at the trial. So I will consider with counsel (if they cannot agree) what order I should make to give effect to my decision.