Strand, London, WC2A 2LL
B e f o r e :
| EUROPEAN CENTRAL BANK
|- and -
|DOCUMENT SECURITY SYSTEMS INCORPORATED
(a company incorporated under the laws of the State of New York, USA)
Henry Carr QC and Piers Acland (instructed by McDermott Will & Emery) for the Defendant
Hearing dates: 23 – 26 January, 29 – 30 January 2007
Crown Copyright ©
Mr Justice Kitchin :
i) Added matter arising out of limitations added to claim 1 by the amendment proposed on 5 February 1999.
ii) Obviousness in the light of
a) the prior publication of GB 1,138,011 ("011");
b) the prior publication of DE 602,563 ("Kurowski"); and
c) the common general knowledge.
iii) Anticipation in the light of the prior circulation of two series of banknotes:
a) the UK 1987 Series D £10 note;
b) the Swiss Sixth series 20 Franc note.
iv) Insufficiency on the basis that there is no sufficient teaching of how to determine the width of the scanning lines of the copying devices.
i) Specialised substrate materials. Banknotes were generally made of good quality paper. Sometimes high quality 100% rag paper was used which is dull when seen under ultra violet light. Coloured fibres and threads were embedded to give the paper added individuality.
ii) Specialised inks such as magnetic and fluorescent inks which were difficult and expensive to obtain.
iii) Watermarks which were first introduced in Bologna, Italy in 1282 and have been commonly used in security printing ever since. Watermarks are made either by varying the thickness of the paper in a mould while it is being made, or by impressing a water coated metal stamp or 'dandy roll' onto the paper during manufacturing.
iv) Printed patterns made using sophisticated and expensive printing techniques such as intaglio printing, which I explain later in this section. These could print with an extremely accurate register and in fine detail.
v) Iridescent foils and structures such as holograms which display a colour or image change when viewed from different angles.
vi) Unique serial numbers which make counterfeiting more time consuming and counterfeit notes easier to identify and track.
vii) Banknotes printed with fine alignment between the printing on each side of the note. Accurate imitation was difficult without printing machinery and technology not readily available to the counterfeiter.
viii) Screen traps designed to create a moiré pattern when a note is reproduced, as I shall explain.
Line and halftone printing
The skilled addressee
Common general knowledge
i) The general principles of physics and optics underlying the technical matters set out in the technical background.
ii) The principles underlying the formation of moiré interference fringes.
iii) The printing methods available for large scale production.
iv) The fact that banknote production would involve more than one printing method and intaglio methods were almost universally used, together with other offset printing processes.
v) The fact that the formation of moiré fringes had been a problem arising from the use of copying processes using halftone screens.
vi) The fact that this problem arose from interference between the halftone screens or between the screens and a pattern in the original image.
vii) An appreciation that colour copiers were likely to become much more widespread, cheaper and of better quality as technology advanced and that there was an incentive to incorporate security features that would address the issues raised by these copiers.
viii) The general principles of electrophotography underlying colour photocopier technology.
ix) Familiarity with the design features of banknotes currently and previously in circulation in other major jurisdictions, including the fact that banknotes commonly comprised many closely spaced lines of different orientations and spacings, whether printed by intaglio or offset printing techniques.
Drawbacks of screen traps
Screening and scanning
Digital colour copiers
"Accordingly, and being long familiar with the phenomenon of moiré that often occurs in printing, he reasoned that what had always occurred as a problem could be turned to the advantage of society in the elimination of the counterfeiting of face – value documents. For the edification of the reader it will suffice to say that the moiré is a serious problem in color reproduction. It is the occurrence of an interference pattern caused by the over printing of the screens in colorplates (similar effects can be observed by superimposing two pieces of a fine grid network such as window screening). Indeed, the technique of rotating half tone screens, when making the negatives for a printing plate, has been developed in order to avoid the moiré interference. Often it appears as the geometrical design that results when a set of straight or curved lines is superposed onto another set. If a grating design, made of parallel black and white bars of equal width, is superposed on an identical grating, moiré fringes appear as the crossing angle is varied from about one second of arc to about 45 degrees. The pattern will consist of equi-spaced parallel fringes; but, if two gratings of slightly different spacing are superposed, fringes will appear (known as "beat" fringes) which shift positions much faster than does the displacement of one grating with respect to the other. "
"It became apparent to the instant inventor, therefore, that the moiré pattern, rather than as an indicator which is gradually removed from an image, may also be used as an indicator of some perhaps latent defect in a document. More appropriately, there had to be some way in which a pattern could be included in an image by printing it in a selected pattern. Then, when the image was viewed through a superposed grid, such as previously discussed, a moiré pattern would be observed according to the degree in which the patterns interfered with each other. Moreover, if one were to reduce the moiré apparatus to its simplest form, that is, such as viewing some background through the common parallel-stake snow fence (suggested by the previous description of parallel black grid lines spaced by parallel white or clear areas of equal width), and if the pattern over which it is superposed is formed of lines and dots that are equally spaced from each other (whether parallel or curvilinear), but a fraction off the pitch (or spacing) of the overlain grid, the observer would be deprived of a high percentage of the background field of vision. Thus, the background image, if formed of the line and dot printed grid, would be rendered nonreplicable to any apparatus being used to record the view. It is this particular aspect of moiré pattern creation that is used by the instant inventor to create this invention. Further, he also recognized that because the modern copy machine, whether it be a standard color tone copier or a laser printer, scanned the image to be copied with a fixed pitch scanning system, it was unnecessary to devise overlay grid means. In fact, the modern replicator contains such a grid in the fixed – pitch, parallel scan format that is used to view the image to be replicated."
"In particular, no one heretofore has found a way to provide an original banknote or important document which embodies the two often-sought features of a copy-proof instrument; for example, one which to the unaided eye is both indistinguishable from a prior (genuine) item and which is capable only of obviously bogus copier replication."
"The problem posed by copier replication has been solved by this invention, which is based upon the serendipitous discovery and novel concepts described below. Consequently, it is now possible, for the first time to produce legal tender paper currency, genuine travelers cheques, original postage stamps, government issued food stamps, important documents or certificates and the like, which to the naked eye are identical to prior items of the same kind but, in fact, have characteristics which reveal copier (especially color) replications to be obvious counterfeits."
" The instant inventor in the course of searching for a solution to this problem accidentally discovered that a color copier replication of an original traveler's cheque cannot itself be used to produce a closely matching copy. Actually, it was found, surprisingly, that no matter how the color copier was adjusted to eliminate blemishes or defects apparent to the casual observer, the copies made from the first copy always had such prominent tell-tales, in one form or another."
 On the basis of his knowledge and skill as an expert in the printing art and the science of optics, the instant inventor recognized that in this discovery he had the key to solving the copier replicating problem. Thus, he conceived the idea of using the bane of the printer to the advantage of the counterfeit preventor. He would use the moiré effect to reveal the bogus color copy of a genuine banknote, for example, by producing the note image lineations in mismatch to the scanner of a color copier. The mismatch would be slight and not noticeable to the naked eye and thereby both basic requirements, which no one else was ever able to meet, could be totally satisfied. Moreover, the cost of producing such counterfeit-proof certificates need not be substantial. "
"The basic method of counterfeit protection teaches the inclusion of lines, dots and/or swirls embodied and integrally formed into art, pictures and other forms of images. The grid lines are made so as to differentiate minutely in vertical and/or horizontal pitch from the linear grids employed by the scanning mechanisms of the machines used to replicate these black-white or colored documents. Generically, such scanning replicators are typically black and white optical reproduction systems, such as office copiers, color copiers, and opticons that are used in conjunction with video systems. Subclassed in this generic group are the new and increasingly common, laser color and black and white optical reproduction systems. After creation of the authentic document, that is, one including the grid lines of predetermined pitch, the primary method of counterfeit protection, as well as the product thereof, have been realized. Any attempt at imitation or replication by means of a scanning-type copier will result in the generation of interference patterns and tones which are readily discernable (by the untrained and naked eye) from the original (or authentic) document in that the aesthetics of the document are distorted, omitted or otherwise completely destroyed in the replication."
"From the foregoing, and in view of the detailed description set forth below, it will be understood that this invention relates to a method producing an article of manufacture or product. Further, in its method aspect this invention comprises the step of producing an electro-optically nonreplicable original-certificate by providing on a matte a lineate pattern of visible image-defining lines which are of predetermined moiré-producing pitch relative to an electro-optic copy machine scan protocol. Otherwise expressed, this method includes the preliminary step of determining the pitch of an electro-optic copy machine scanner."
"The solution of the problem to the counterfeiting of printed documents lay in a form of reverse engineering wherein the recognition of a grid form of scanning in all replicating devices, and a knowledge of the moiré effect, led the instant inventor to reason that a distorted image would result any time a grid-like scanning pattern failed to map any discrete part of an authentic document into its replica."
"…. if the Figure 1a print were arranged cleverly so as to ensure that the greater part of the image was not picked up by the scanning protocol, the resulting copy would be highly distorted, full of moiré interference patterns and significant omissions."
A A method of making a document that is not faithfully replicable by scanning-type copying devices, the document using a visible original image comprising art, pictures and/or image forms made of curvilinear lines, dots and/or swirls, the method comprising the steps of
B determining the scanning pitch distance (p) and width of the scanning lines of the copying devices;
C1 producing a grid pattern of parallel lines having a pitch distance (d) minutely more or less than the scanning pitch distance (p),
C2 the difference between the pitch distance (d) of the parallel lines and the scanning pitch distance (p) being within a range from about one-half the width of the scanning lines to about one-half the scanning pitch distance (p); and
D1 overlaying the grid pattern on the original image to produce on the document a printed image which comprises the original image having a superimposed transmitted or obstructed print pattern conforming to the grid pattern
D2 and in which the print pattern normally is not discernible by the naked eye, such that the original image and the printed image appear to the naked eye to be generally the same,
E the print pattern causing visibly discernable interference (e.g. moiré) patterns and/or false tones, colours or omissions to be produced in the printed image in copies of the document made by the copying devices.
A method in accordance with claim 1 characterised by the parallel lines being uniformly spaced.
Integer A: "Scanning-type copying device"
Integer A: "The document using a visible original image"
Integer B: "determining the scanning pitch distance (p) and width of the scanning lines of the copying devices"
"Further, he also recognized that because the modern copy machine, whether it be a standard color tone copier or a laser printer, scanned the image to be copied with a fixed pitch scanning system, it was unnecessary to devise overlay grid means. In fact, the modern replicator contains such a grid in the fixed – pitch, parallel scan format that is used to view the image to be replicated."
Integer C1: producing a grid pattern of parallel lines having a pitch distance (d) minutely more or less than the scanning pitch distance (p),
Integer C2: the difference between the pitch distance (d) of the parallel lines and the scanning pitch distance (p) being within a range from about one-half the width of the scanning lines to about one-half the scanning pitch distance (p); and
Integer D1: overlaying the grid pattern on the original image to produce on the document a printed image which comprises the original image having a superimposed transmitted or obstructed print pattern conforming to the grid pattern
Integer D2: and in which the print pattern normally is not discernible by the naked eye, such that the original image and the printed image appear to the naked eye to be generally the same
Integer E: creating interference patterns
Claim 2: Parallel lines are uniformly spaced
"The decision as to whether there was an 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:
(a) To ascertain through the eyes of the skilled addressee what is disclosed, both explicitly and implicitly in the application.
(b) To do the same in respect of the patent as granted.
(c) 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."
Comparison of the disclosures
"A method for making a nonreplicable image comprising placing on a suitable medium visible and distinct lineations formed into various patterns of lines, dots and swirls to create said image, said lineations having a predetermined lineation pitch which varies from a conventional copy machine scanning pitch by as little as the thickness of a scanning line of said machine and as much as 50% of the spacing between said machine's scanning lines, whereby when said image is copied by said machine, a moiré-skewed copy of the image results thus frustrating the photocopy replication of said nonreplicable image."
"The method of making an original certificate that is capable only of electro-optically inaccurate replication, said method comprising the step of placing on a substrate a lineate pattern of visible image-defining lines, said lineate pattern being of predetermined omission-creating, moiré producing, mismatched pitch relative to the scanning pitch and azimuth of an electro-optic copy device"
"An electro-optically nonreplicable document comprising an image defined by a plurality of lineations which comprise lines, dots and swirls, said lineations of predetermined omission-creating, moiré producing pitch […]. "
"When the Figure 1b pattern is overlain the Figure 1a printed pattern, a distortion 20 in the Figure 1a results as shown in Figure 1c. The instant inventor defines the Figure 1c pattern as a type of moire distortion pattern resulting from a mapping of the Figure 1a pattern by the function of the Figure 1b grid overlay. Those of ordinary skill will also recognize that, were the function to be reversed, that is, the grid lines 17', 19' of Figure 1b were to become the areas of image transmittal (rather than obstruction) and the areas denoted k to be areas of obstruction or opacity, the Figure 1c map would depict the compliment of the illustration 20 actually shown."
"If, for example, the horizontal lines 17 of Figure 1b were the nonscanned areas in a copy machine protocol, and the interstitial or "see through" areas corresponded to the actual scanning lines, the illustration of Figure 1c would in reality be the resultant replica or counterfeit." (emphasis added).
"The basic method of counterfeit protection teaches the inclusion of lines, dots and/or swirls embodied and integrally formed into art, pictures and other forms of images."
"After creation of the authentic document, that is, one including the grid lines of predetermined pitch, the primary method of counterfeit protection, as well as the product thereof, have been realized." (emphasis added)
"Further, in its method aspect this invention comprises the step of producing an electro-optically nonreplicable original certificate by providing on matte a lineate pattern of visible image-defining lines which are of predetermined moiré producing pitch relative to an electro-optic copy machine scan protocol. Otherwise expressed, this method includes the preliminary step of determining the pitch of an electro-optic copy machine scanner."
"In its article of manufacture or product aspect this invention then, likewise briefly stated, is an electro-optically nonreplicable original certificate which bears an image defined by a plurality of lines of predetermined moiré-producing pitch relative to the scan lines or pattern of an electro-optic copy machine." (emphasis added)
"….the matter relied upon as prior art must disclose the 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  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. The flag has been planted, even though the author or maker of the prior art was not aware that he was doing so."
i) Identify the inventive concept of the claim;
ii) Identify the common general knowledge of the skilled team;
iii) Identify the difference(s) between the prior art under consideration and the inventive concept of the claim;
iv) Ask whether the difference(s) would have been obvious or required invention.
Obviousness - the 011 patent
The disclosure of 011
"According to the present invention printing matter is provided with one or more patterns of configurations which prevent successful counterfeiting by half-tone screening reproduction processes by virtue of the intersection of the patterns on the printed matter with the rectangular screen grid pattern of the half-tone reproduction screen so as to make it substantially impossible to avoid creating a Moiré pattern on the reproduced document." (p.1, lines 33 - 43)
"It is the interaction of the screen with the pattern on the original that results in the creation of a Moiré pattern, as will be more fully explained below. For example, assuming that a counterfeiter uses a half-tone screen having a grid spacing of 100 lines per inch, a bank note bearing a configuration of parallel straight lines having a spacing approximately 100 lines per inch will, if the angle of intersection of the screen lines with the bank note lines is small enough, produce a Moiré pattern." (p.1, lines 58 – 74).
"It is apparent that not only line patterns but also patterns of dots may give rise to Moiré patterns when intersected by a rectangular or other grid. For example, the series of parallel lines shown in Figure 3 may be approximated by a dot pattern in which the dots lie on the locus defined by the parallel lines." (p.3, lines 92 – 99)
"Accordingly, an arrangement of dots in which there is some geometrical regularity may, when intersected by a rectangular grid, form a Moiré pattern. A special example of such an arrangement is a design picture, portrait, etc. in dot pattern form, obtained by the use of a half-tone screen." (p.3, lines 103-109)
Indeed, Claim 19 is specifically directed to this:
"Printed matter as claimed in claim 18, in which the pattern or configuration is a dot pattern obtained from a design by means of a half-tone screen."
"Patterns of portions of concentric circles are shown in the lower left and upper right corners of the bank note. The concentric circle pattern in the upper right corner is composed of lines of uniform width and spacing, and therefore would not be effective against all possible half-tone screen grids. However, if a plurality of concentric circle patterns of different spacings were included in the bank note, this deficiency could be overcome."
Inventive concept, addressee and common general knowledge
Differences between the inventive concept and 011
Do these differences represent obvious steps?
i) The skilled addressee would at once perceive from reading 011 that the problem of the phenomenon of moiré that often occurs in printing was being "turned to the advantage of society in the elimination of the counterfeiting of face-value documents" and that at this level the concept of the Patent is the same as that of 011. The skilled addressee would also immediately appreciate that the principle at work in 011 was the presence of a grid in the document to be copied interfering with the grid imposed by the reproduction system. Moreover, the skilled addressee, on the basis of his understanding of the physics of moiré generation, would understand that the grid imposed by the reproduction system was a regular sampling protocol that sampled the document to be copied in mismatch to the grid overlain on the document.
ii) Further the skilled addressee would understand that the frequency of the sampling protocol at the input scan of high-end scanners was too high for moiré to be produced – the corollary is that it was understood that moiré would be formed if the frequency of the rulings was high enough or the frequency of the scanning lower.
iii) By 1989 it was common general knowledge that moiré inducing rulings to combat the use of screens could be used; indeed it was common general knowledge that such moiré inducing rulings were used. It was also common general knowledge that a new generation of copying device called digital copiers were available (and would become more available) – of which the Canon CLC was a motivating example.
iv) Any skilled addressee wishing to address the possibility of combating counterfeiting using these machines would want to find out how they worked. The skilled addressee would either know or find out how a CCD array worked and that they impose a regular sampling protocol. Knowing that a halftone screening process is merely an alternative regular sampling protocol, the skilled addressee would immediately realise that techniques used to defeat copying by halftone screening would equally apply to colour copiers using CCD arrays to sample.
v) The skilled person would therefore immediately see that a "scan trap" was the same as a "screen trap" in its moiré producing properties. Accordingly there is no invention in applying the moiré creating disclosure of 011 to the new generation of copiers.
"The basic idea of using moiré effects for improving the security from counterfeiting of printed products has been specified in GB-PS 11 38 011. Examples are given therein for suitable optically active structures with one or a plurality of degrees of freedom (i.e. for complete characterisation of the type of periodicity of the structures it is necessary to specify one or a plurality of values of the spatial frequency) having spatial frequencies which are fixed or vary quasi-continuously as a function of the spatial coordinate. However, with the structures specified therein depending on the screen used for the reproduction, a moiré effect can only be observed for specific screen spatial frequencies or using the likewise specified structures with varying (continuously increasing or decreasing) frequency only at quite specific locations of the optically active structures which change its position and/or its appearance according to the spatial frequency of the reproduction screen and as a consequence is not easily recognisable. "
"Q. In your reports, you have mentioned the BPC as really, if I may paraphrase it in this way, the hub of knowledge, the most sophisticated western European banks discussing security measures. Correct?
Q. This is annexed or a part of the BPC general report in September 1988.
Q. It is specifically considering the very problem that you were concerned with at the time posed by the Canon colour copiers. Yes?
Q. It has photocopied many notes under those copiers. Yes?
A. A number of notes, yes.
Q. It considers many different solutions. We have looked at some of them.
A. We have looked at some.
Q. It does not mention moiré effect or screen traps as a solution at all, does it?
A. No, it does not.
Q. Screen traps were known about in half-tone screen printing. Indeed, you say, and I am sure you are right, that by this time it was common knowledge amongst those in the security industry. Yes?
A. I believe it was, yes.
Q. You say, I think, that it would be obvious to take that solution and use it to solve the problem of the Canon CLC. Yes?
A. Yes, but the screen traps that were in existence then were aimed at half-tone reproductions, not at colour copies.
Q. Exactly. When testing these notes with those screen traps on aimed at half-tone reproductions, it does not appear to have occurred to these experts that one could take that solution and adapt it for the colour scanners, does it?
A. On the face of it, I have to agree, yes.
Q. If it had been obvious, then of course the more elaborate solutions, such as iridescent inks, and so on, there would be no need to investigate them because that would be the solution.
A. That is quite possible, but I believe that the people here may not have seen screen traps as a solution or they may have done. I saw this report, for sure; but I was not in very close contact, apart from the BPC, with the Bank of Spain or the FNMT at that time. They were not part of my close associates. They were part of this larger group, and I am surprised that they did not."
"Q. Right, and how would you do that?
A. Clearly you have to study colour copies, but the view was that you would have to try to get your lines perhaps more dense, stronger, if you like, the lines that are making it, into areas which people would notice more than perhaps we had done so in the past. This was a developing situation which we have to try and see whether we can improve it.
Q. That is it, is it? You would make the lines denser in other areas?
A. No. You may have to do them in different formations or whatever. There was a lot of things that you could actually apply -- you have to use your intelligence to do it ---
Q. You have to use your imagination, would you not?
A. Yes, I suppose to some extent you would. You have to use some knowledge, but then you have to use knowledge to produce banknotes.
Q. I understand that you may have been brainstorming about how to adapt screen traps in the ways that you have just suggested, but the experts that we have looked at in their reports do not even seem to regard that as a way forward at all, do they, as far as one can tell?
A. No, but I am not sure that the experts that you are talking about represent the totality of the experts in the field.
Q. So some other expert might have thought about adapting screen traps.
A. Some others, yes.
Q. And they would have thought about perhaps making the lines more dense.
A. I suspect they would, yes.
Q. And putting them in other areas.
A. I believe so, yes."
Obviousness – Kurowski
Disclosure of Kurowski
"As a safety feature, periodic or quasi-periodic optically active structures composed of sub-structures in the manner of a pattern repeat and/or suitable combinations of such structures are applied to the banknote or a security paper which, when an attempt is made to produce a screen reproduction by means of a scanner or a reproduction camera, induces an interference effect as a result of the interaction between a material or electronically produced screen and the applied optically active structure, which is known under the name "moiré effect" or "moiré" for short." (p.4, lines 10-15).
"A moiré effect of the type described previously only occurs in screen reproduction but not in half-tone reproduction. Half-tone reproductions are reproductions produced, for example, using photocopiers or photographic materials."
"a) The moiré effect occurs for a quite specific spatial frequency range e.g. from 50 to 60 structural elements per centimetre in the screens used for the reproduction.
b) The moiré effect only occurs for certain angular positions of the master to be reproduced, which contains the moiré producing structure, relative to the reproduction screen so that the moiré effect can be largely suppressed during the reproduction by changing the position of the screen.
c) The moiré effect only occurs in certain sections or areas of the moiré producing structure." (p.6, lines 6-11)
"The object of the invention is to eliminate these disadvantages and provide security papers with moiré producing structures where the moiré effect occurs over a wide range of spatial frequency of the screen usually used for reproduction purposes, the moiré effect is formed over a wide range of optically active structures on the security paper to be protected in a defined and therefore clearly recognisable manner and the moiré effect virtually cannot be suppressed by twisting the screen." (p.6, lines 13-16)
Inventive concept, addressee and common general knowledge
Differences between the inventive concept and Kurowski
Do these differences represent obvious steps?