Case No: HC 2000 No. 963
Neutral Citation Number: [2002] EWHC 737 (Ch)
IN THE HIGH COURT OF JUSTICE
CHANCERY DIVISION
PATENTS COURT
Royal Courts of Justice
Strand, London, WC2A 2LL

Date: 25 April 2002
B e f o r e :

THE HONOURABLE MR JUSTICE LADDIE
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	(1) stena rederi aktiebolag
(2) stena line aktiebolag		
Claimants
	
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	(2) irish ferries limited	Defendant	

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Mr Richard Arnold QC and Mr Hugo Cuddigan (instructed by Barlow Lyde & Gilbert for the Claimants)
Mr Richard Miller QC and Mr Douglas Campbell (instructed by Holman Fenwick & Willan for the Defendant)

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Hearing dates: 15, 18 – 19 February 2002

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Approved Judgment

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

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Mr Justice Laddie

  
Mr Justice Laddie: 
1.	In this patent infringement action, the claimants are Stena Rederi Aktiebolag and Stena Line Aktiebolag who are respectively the registered proprietor of and exclusive licensee under European Patent (UK) No 0 648 173 entitled “Superstructure for Multihull Vessels”. I shall refer to them together as “Stena”. The only remaining defendant is Irish Ferries Limited. It operates a ferry service running between Dublin and Holyhead. On that service it employs a high speed catamaran called the “Jonathan Swift”. 
2.	Although operation of that ship was originally said to infringe all five claims in the patent, the issues now before the court have become somewhat more narrow. Stena do not defend the validity of claims 1 and 2 of the patent but they do defend the validity of claim 3, which is dependent upon those two. Irish Ferries disputes validity of Claim 3, denies that the acts complained of fall within the scope of the claim and also runs a defence of non-infringement based on s 60(5)(d) of the Patents Act 1977.
The Patent in Suit
3.	The patent, which has a priority date of 9 July 1992, is, as its title suggests, concerned with improvement in multihull vessels such as catamarans. Its field of application is particularly suited to large high speed multihull vessels which are likely to be used in rough seas although the claims are not so limited. 
4.	Any vessel is subject to various forces which tend to distort its shape. This is particularly marked in multihull vessels such as catamarans. As the defendant’s expert, Mr Anthony Marchant, explains in his expert report, when in motion, such vessels are subjected to bending and torsion stresses and also to the associated shear stresses. Each hull may be individually subject to bending (either in the sense of ‘sagging’, where the middle is below the ends, or ‘hogging’ where the middle rises above the ends) and so may the vessel as a whole. Torsional stresses will arise where the two hulls of the catamaran twist with respect to each other. As a result of the bending and torsional forces on the hull, direct compression, tension and shear forces will arise. When the vessel is sagging, the ends of the top of the vessel will tend to move towards each other with the result that the top will be “squashed”, while the reverse will happen at the bottom which will be “stretched”. The result is that the top will be in compression and the bottom in tension. When the vessel hogs, it will be the bottom which is in compression and the top which is in tension. The sides and any continuous longitudinal vertical structure will carry the shear forces so created. Such shear forces act in the plane of the vertical members.
5.	 Many of the forces are local, but some are global and have an impact on the whole structure. Needless to say, the larger and faster a vessel is and the more adverse the sea conditions it encounters, the greater will be the forces to which it is subjected. A vessel must be designed in a way which enables it to deal with these forces. This means that the designer has to have regard both to the global and local forces to which the vessel will be subjected in its intended use – for example a high speed ocean-going vessel will be subject to much higher forces than the same vessel operated at low speed in a calm fjord. However for small vessels, although the global forces have to be kept in mind, normally catering for the local forces will be sufficient to ensure that the vessel has adequate seakeeping qualities.
6.	Thus local forces are those which act only on one part of the overall structure whereas global forces act on the whole structure. Local forces are readily addressed by considering the properties of the structure in the particular area of concern. For instance, one might address local forces associated with vehicle mass in a vehicle-carrying ferry by strengthening the floor of the vehicle deck. Global forces are instead addressed by considering the structure as a whole. Every part of the structure will try to work to resist the induced stresses when the vessel bends and twists under the actions of the waves on the vessel unless specifically isolated. 
7.	As Mr Marchant explains;
“In the vast majority of vessels (not limited to catamarans), both local and global strength is obtained by using stiffened plates. It is, and was before July 1992, normal practice to use a stiffened plate structure for the hull (and superstructure) because the vessel is required to be watertight and such a plated structure is a convenient method to achieve this whilst simultaneously contributing to the global strength. The stiffening is achieved by the combination of the external plating itself and the use of stringers, or other components which are connected to the external plating to increase its rigidity. The external plating and stringers are then connected to the frames, beams and girders which form the three-dimensional structure of the vessel.” 
8.	With that background, I can turn to the patent. It sets out the problem which it seeks to address in the following passage:
“Large, high-speed catamarans may have a length of 100 metres, a hull height of about 12 metres, a width of 40 metres and propulsion machinery which will propel the vessel at a speed of 35 knots, for instance. The free space above the cargo deck may be 5 metres, for instance. It will be seen from these factors that when in motion, the vessel will be subjected to large bending and torsion stresses and also to large deformation forces, and that the aforesaid side walls are therefore conventional, simple metal plate walls which are extended to the long sides of the superstructure, so as to form the stiffest possible side-beam structure together with respective hulls. Nevertheless, the stresses and deformation forces are still high in those regions which form the long side walls of the passenger space, which limits the possibility of providing window openings in these walls. In conventional seagoing vessels, it is necessary to round the window opening so as to reduce the risk of stress concentrations. In spite of this, however, the elastic deformation of these window openings still remains highly troublesome and places high demands on the elastic attachment of the window panes or window glass.” (patent Col. 1 lines 20 – 41)
9.	The patent then states:
“Accordingly, one object of the invention is to provide in multi-hull vessels of the aforesaid kind a superstructure construction which achieves a reduction in the deformation forces acting on the side walls of the passenger space, for instance, in operation, while providing the thus stiffened side-wall construction of the superstructure with larger free surfaces in which window glass, for instance, can be fitted. Alternatively, covering material can be fitted into the openings or on the frames.”  (Patent Column 1 lines 42 to 50)
10.	It will be appreciated that the patent is seeking to achieve a number of benefits at the same time. It wants to achieve a stiffened superstructure while still allowing for the provision of large windows in that superstructure. Thus the superstructure is incorporated into the main structure of the vessel and helps to deal with global forces but, at the same time, has holes along its length which allows for the provision of windows. The latter has to be done in a way which does not seriously undermine the former. This dual objective is achieved by incorporating the superstructure into the vessel’s global structure so that it contributes to the global strength of the vessel but, at the same time, providing essentially triangular shaped window openings in the side walls. These triangular apertures create a braced side wall. The patent illustrates this arrangement in a series of figures, two of which are attached to the end of this judgment in Annex 1. Figure 2 in that Annex has been slightly modified, as will be explained below.
11.	Figure 1 is a schematic cross-section of a catamaran according to the invention. The vessel has two parallel hulls (2). Above and connected to them is a cargo deck (3). There are outer walls (4) supporting a superstructure (7). A space for cargo and vehicles is shown with the walls (4) on each side and the cargo deck (3) below it. The specification describes the superstructure as follows:
“The superstructure 7 is comprised of a plurality of flat latticework beams 5 whose longitudinal axes coincide essentially with the longitudinal axis of the vessel and the planes of which are vertical. In particular, a latticework beam 5 is provided along each long side of the superstructure 7. In the illustrated case, the superstructure includes four beams 5 each being located above an associated bulkhead 44.” (Patent Column 3 lines 15 to 24)
1.	The arrangement of the latticework beams is illustrated more clearly in Figure 2. The latticework includes top and bottom longitudinal elements. To make the Figure, which is a perspective view, more easy to understand, the marking of these longitudinal elements has been altered. As shown in the Annex, the pair of top and bottom elements nearest to the viewer are identified as (51A) and (52A). The more distant pair are (51B) and (52B). The two top elements are connected to either end of lateral cross members (55). The two bottom elements are connected to either end of lateral cross members (56). Furthermore on each side wall, the top and bottom elements are connected together by two diagonal struts (53) and (54). The result is the creation of a structure which looks like a series of skeletal tents running across the superstructure side by side. It will be appreciated that this structure creates a side surface consisting of a number of adjoining triangles – (54, 53, 52A), (53, 54, 51A), (54, 53, 52A) and so on. These form the glazing apertures for the windows. As the specification explains (Column 3 lines 32 to 41), only very small changes will occur in the size and shape of these triangular apertures even when the vessel moves at high speed through a heavy sea. This enables the apertures to be glazed essentially to their full extent. In other words the bracing created by the diagonal struts and the top and bottom elements is sufficiently rigid to allow the apertures to function as window frames. 
2.	I think it is accepted by the defendant this is not the usual design of windows on the side of a vessel. They are normally of the shape illustrated in Annex 2, consisting of a series of vertical, substantially rectangular openings. The edges are rounded to minimise the chances of fractures which would occur at the corners if they came to a sharp point. 
3.	The cross-bracing created by the struts and longitudinal members creates a rigid structure which adds to the global strength of the vessel, but in a way which leaves large open spaces for windows. Furthermore the patent describes the latticework structure as being connected to the floor and ceiling of the superstructure.
 The Claims
4.	As indicated above, the only claim in issue is Claim 3. It is dependent upon claims 1 and 2. The three claims are as follows:
Claim 1: 	“(1) A multihull vessel of the catamaran type comprising two or more hulls (2) which extend in mutually parallel and horizontally spaced relationship and which are mutually joined by means of one or more decks (3) and further comprising an overlying space in a superstructure (7) supported by one or more wall structures (4) that extend from respective hulls (2) characterised in that walls in the superstructure are formed by latticework beams (5) whose longitudinal profiles (51, 52) extend horizontally and whose planes are oriented generally vertically and in that the latticework beams (5) are connected firmly to those walls which support the superstructure (7) from the underlying hull.”
Claim 2: 	“A vessel according to claim 1, characterised in that the longitudinal profiles (51, 52) of the latticework beams (5) are connected to the roof structure (58) and the floor structure (59) of the superstructure (7), said floor structure and said ceiling structure being constructed to contribute to the overall strength of the vessel and to strengthen the bending resistance of the longitudinal profiles of the latticework beam.”
Claim 3: 	“A vessel according to claim 1 or 2, characterised in that windows are provided in the free spaces defined by longitudinally extending profile elements and struts in the latticework beams that define the side walls of the superstructure.”
5.	Since a point of construction taken by Mr Miller QC on behalf of Irish Ferries turns on the wording of claim 4, that is set out below:
Claim 4:	“A vessel according to claims 1 or 2, characterised in that a latticework beam forms at least partially the body of a partition wall, wherein partition wall material is applied to the sides of the beam or in the free spaces defined in the beam by the longitudinally extending beam profile and struts, said wall material being essentially free of appreciable deformation forces.”
6.	 The expression “latticework beam” is not a term of art but what is meant by these words is indicated by the following passage in the patent:
“In principle, the term shear-force absorbing lattice-work beams as used in the present context is meant to define two essentially parallel profiled elements which are mutually joined by struts that extend generally obliquely between the profiled elements and that are inclined in alternate directions. The struts may be straight, so as to form generally triangular openings in the beam. Alternatively, the struts may have the form of circles or ellipses which lie tangential to both the longitudinal profiles and to each other. The actual latticework frame itself imparts the desired shear-force stiffness to the superstructure walls, thereby enabling the walls to be covered [by] wall material without needing to take into account deformation forces or mechanical strength in regard of the actual vessel construction.”
7.	Although a number of points on construction were argued, the allegedly inventive concept underpinning claims 1 to 3 taken together can be summarised as the use of the latticework of diagonal struts and longitudinal members to create, in conjunction with the roof and floor to which it is connected, a force absorbing part of the superstructure of the vessel while simultaneously creating window apertures in it. What is created may be likened to a box with rigid sides. It will resist not only hogging and sagging but also the torsional forces created by the hulls trying to twist with respect to each other.
Construction
8.	Most of the issues relating to construction will be dealt with below in the section of this judgment concerned with infringement. However there is one point which can be dealt with conveniently at this stage. The specification and claims refer to a “superstructure”. That is a term of art, at least among naval architects. There are a number of definitions of it used by different marine classification societies, at least in respect of certain types of ships. The claimant’s expert witness, Mr Kanstrup, sets them out in his report. They are essentially the same. For example, the definition to be found in Lloyds Register is;
“a decked structure on the freeboard deck, extending from side to side of the craft, or with the side plating being less than four percent of the breadth, B, inboard of the shell plating.”
9.	This definition, like all the others, applies to ships which have a freeboard deck, that is to say the uppermost complete deck exposed to weather and sea which has permanent means of closing all openings in the weather part. However Mr Miller argues that it does not read happily onto an integrated structure like the Jonathan Swift because that ship has nothing which can be identified as the freeboard deck. The accepted definitions were not designed to apply to this sort of ship. Therefore, if the patent is adopting the term of art known to naval architects, it is in this respect unclear. Mr Miller concedes that this makes no difference on the issue of infringement because, whatever “superstructure” means, it is accepted that the Jonathan Swift has one. However a correct understanding of this term may be of importance to one piece of prior art. On the other hand Mr Arnold QC, who appears for Stena, says that the reader of the patent would understand the term to have its accepted meaning from the art. He says that this is not a problem because a freeboard deck can be identified in the Jonathan Swift and the claimant’s expert, Mr Kanstrup does so in his report. 
10.	I am not persuaded that the Lloyds Register definition or the definition employed by any other marine classification society can be written into this patent. As both witnesses agree, the patent appears to have been drafted by someone who was not  familiar with the terminology used by naval architects. There is nothing to suggest that in using the word “superstructure”, the inventor was intending to adopt any such technical definition. Nor does it appear that the benefits claimed for the invention are dependent on the latticework arrangement being located in a part of the ship which falls within any such definition. 
11.	The meaning of the expression must be discerned from the patent itself. The specification describes a vessel in which there is at least one deck for taking cargo. Above it, or them, is the superstructure. This is carried through to the claims which refer to “one or more decks (3)” with an “overlying space in a superstructure” in which there will be the latticework arrangement and windows. Therefore the superstructure is the overlying window-containing part of a multi-deck vessel. Put another way, if the latticework arrangement is located in an upper part of the vessel and over one or more decks, then it is in the superstructure.
Validity
12.	The defendant attacks validity on the basis of lack of novelty having regard to US Patent 522,348 published July 3, 1894 (“Martini”), and obviousness having regard to each of (i) common general knowledge (ii) Martini and (iii) a ship built by Austal Ships (Pty) Ltd in Western Australia called the “Bali Hai”. A further pleaded prior publication, Japanese laid-open patent application No. S60-206, 797 (“Hitachi”), was abandoned during Mr Miller’s closing submissions. The novelty attack was dependent upon the expression “latticework beam” in claim 1 covering a rectangular lattice. However the definition in the patent emphasises the need for oblique struts. It does not cover a rectangular lattice, which would not achieve that strengthening which is the cornerstone of the invention. Therefore I can concentrate on the obviousness arguments. At the trial most of this centred on the issue of obviousness in the light of the common general knowledge. Before turning to that, it is necessary to identify the inventive concept which is central to the combination of claims 1, 2 and 3. 
The invention
13.	 The basic concept behind the patent has been considered at paragraph 18 above.  As Mr Miller puts it, the patent is an “idea” patent. It is not concerned with the minutiae of designing a superstructure. It is not suggested that once one has the idea of using a latticework both for strengthening and to provide window openings, there would be any  difficulty in understanding or applying it nor in making the box structure which incorporates the floor and ceiling of the superstructure.
Man Skilled in the Art 
14.	 In this action each party has relied on the evidence of an expert. As mentioned already, the experts called are respectively Mr Kanstrup for Stena and  Mr Marchant for Irish Ferries. Each has been criticised by the other party. In the case of Mr Marchant it is said that he is far too expert to give reliable evidence on obviousness. Although similar criticism could be levelled at Mr Kanstrup, the main attack on his evidence is on the basis that his expertise did not extend to building large catamarans. Before considering their evidence and the issue of obviousness, it may be worthwhile to repeat a passage in Lilly ICOS LLC v Pfizer Ltd [2001] IP & T 190:
“The question of obviousness has to be assessed through the eyes of the skilled but non-inventive man in the art. This is not a real person. He is a legal creation. He is supposed to offer an objective test of whether a particular development can be protected by a patent. He is deemed to have looked at and read publicly available documents and to know of public uses in the prior art. He understands all languages and dialects. He never misses the obvious nor stumbles on the inventive. He has no private idiosyncratic preferences or dislikes. He never thinks laterally. He differs from all real people in one or more of these characteristics.” (paragraph 62)
15.	This passage is of relevance here because it emphasises the difference between the notional addressee of the patent and the type of expert who has been called to give evidence in this trial. Both Mr Marchant and Mr Kanstrup struck me as immensely able and inventive. I think both of them accepted that they were much more likely to engage in lateral thinking than many other naval architects. This does not mean that their evidence is valueless, but it does mean that I have to guard against abdicating my task in deciding the issue of obviousness to the views, no matter how honestly held, of the experts. 
Common General Knowledge
16.	There appeared to be no real differences between the parties as to the state of the common general knowledge at the priority date. Naval architecture is conservative and that conservatism has been encouraged and reinforced by the desirability of following what are known as classification rules – that is to say accepted architectural criteria which are set by the Classification Societies and which play a big part in the ship design. These are conventional rules which make it easier for a ship to obtain classification as being seaworthy. However there were no such conventional rules designed expressly for high speed catamarans. The need to deal with local and global forces was well established. Furthermore the use of bracing using diagonal members to make a structure stiff was well known. Mr Marchant gave extensive evidence on this subject. He pointed out that such structures were extremely well known and had been for a very long time. He referred to the well known Warren girder which is to be found on the sides of many railway bridges. Indeed, one only needs to look at any building site to see cross-braced structures used in profusion in cranes. They make the cranes light but rigid. Mr Marchant said that this was just a standard engineering device that could be employed in any structure to increase its resistance to forces. He explained that by “standard” he meant that it is one which has been familiar to engineers for many years. He said that it was well known to use such structures in the aircraft industry where it is necessary to design light fast vehicles. He is in a particularly good position to talk about the latter industry – probably unlike most naval architects – since he had trained in it. 
17.	Mr Kanstrup also agreed that these types of structure were well known. He put it as follows in his expert report:
“I have no doubt that latticework is, and was in 1992, a generally well-known way to transfer shear forces in a structure. Passenger link spans are often constructed by joining two horizontal mutually spaced decks by vertical latticework bulkheads in each side. Such bridges would surely be within the knowledge of the skilled addressee.” (paragraph 122)
18.	Notwithstanding this, Mr Kanstrup said that he did not believe it was obvious to apply this type of arrangement in the superstructure of a ship in the way that Stena has. He described the Stena arrangement as clever and elegant. He told me that when he first saw the Stena idea he thought it “brilliant”. On the other hand Mr Marchant thought it was an obvious idea to employ. He thought he would have suggested it. I have no doubt that both witnesses were offering their honest views of the matter. 
19.	Notwithstanding the fact that braced beams are well known structural devices, the fact is that they have not been used at all extensively in ship superstructures. This can be gathered, indirectly, from a passage in Mr Marchant’s evidence: 
“Other beam structures are, and were in July 1992 well known at least in principle to the naval architect and structural engineer. Particularly I have in mind the structure referred to as a latticework beam in the patent. Although this could also be referred to as a frame, the same theoretical principles of a beam apply the forces within the beam are those of compression, tension and shear. 
Examples of this approach can be found in early hovercraft (see Appendix B, Items 1(a) and 1(b)). A similar concept can be found in the geodesic structure employed in my own Kristiansand presentation (see Exhibit “AM-1” to my witness statement in this matter), and in the super-outrigger vessel described by Nathan and Howard Daniel in their presentation to the High Speed Surface Craft Conference 1990 (Appendix B, Item 2). 
Other examples of beam structures used in vessels include the Martini patent design and the latticework structure shown in the patent in suit. I have also been shown an example of a beam structure in a pre-July 1992 riverboat design (Appendix B, Item 3), which did not come as a surprise to me.” (paragraphs 33 – 35)
20.	The reference to use in a hovercraft, is a reference to a use deep within the structure of the hovercraft. It is in no way similar in application to the Stena arrangement. The Daniel arrangement was a proposed experimental design for an outrigger for multihull boats. The bracing was not used in the superstructure. It is, again, quite unlike the Stena arrangement. The poor quality of the illustration in the court bundles makes it impossible to reproduce this experimental design in an annex for the purpose of this judgment. The Martini reference is to the Martini patent of 1894, which I consider below. The “pre-July 1992 riverboat” is a reference to a paddle steamer of the sort which would have been familiar to Mark Twain. It is dated 1927. An illustration of it is set out in Annex 3. It will be seen that there is no latticework structure in the passenger-carrying superstructure, but there is some diagonal bracing along each side of the ship where passengers may walk. It is an open structure and therefore plays no part in the sea keeping qualities of the ship. Mr Marchant’s geodesic structure is a most unconventional design which he was putting before a conference in 1988. It is clear from the rest of Mr Marchant’s paper in which this design was disclosed that it was thought by him to be quite unusual. Indeed, a large part of his paper is directed at encouraging the audience to adopt what Mr Marchant describes as a “more radical approach” to design. He says that, for progress to be made, designers and operators must have “courage … to explore the possibilities”. He advises them to turn to other industries, such as the aircraft and automotive industries for ideas. He says that they must adopt “freedom of thought”. It is clear from this document and from much of Mr Marchant’s evidence, particularly under cross-examination, that he viewed naval architects, at least when engaged in the design of displacement vessels, as being backward looking. In putting forward his geodesic design, he was trying to convince his audience to think more broadly than they were used to and to consult other industries to see whether they had solutions which could be applied to modern ship designs. 
21.	Mr Marchant’s expertise and breadth of vision was apparent throughout his oral evidence. He drew together examples of designs which had been employed in a variety of fields to show how he would have thought of using the patented arrangement. For example, beside relying on railway bridges and hovercraft designs he also relied on the use of a latticework beam under the outer skin of the Boeing “Clipper” flying boat. 
22.	The fact remains that, notwithstanding the isolated instances referred to in the last above quoted extract from Mr Marchant’s evidence, latticework beams were rarely used externally on ships and, on the basis of the material adduced in this court, never as part of the outer, weatherproof skin. Mr Marchant explains this as follows:
“Beam structures are, and were before July 1992, rarely used externally in vessels because one then has to add something to keep the water out, and the interaction between this covering and the beam structure may introduce complications of its own. Where only weather tightness is required, eg above the weather deck, then a beam or frame structure could conveniently be used.”
The word “could” in the last sentence of this passage is not to be confused with “were” or “would”. 
23.	Mr Miller argues that the fact that a latticework structure has not been used before in the manner set out in the patent, either in conventional displacement boats or in catamarans, is because there was no need to do so. Such a design could have been used before. This was a matter touched upon by Mr Marchant during his oral evidence.
“Judge: 	Mr. Arnold has just taken you through some of these handbooks which explain how trusses can be used to make strong light-weight structures, particularly in aircraft. If you had been involved -- do not worry about other naval architects -- would you have adopted the sort of things that we see in Bruhn for making smaller catamarans giving them the strength that you need to enable them to go fast, because you would still get the advantages of saving of weight, and so on? 
A.	Indeed. I did not do it, probably because we were taking care of global forces through the structure itself in other ways. 
Q. 	But could these have been applied? 
A.	I could have done it. 
Q. 	How long ---- 
A.	I designed my first catamaran in 1967, my Lord, so I could have well done it then.”
24.	I accept that Mr Marchant might well have thought of using this type of design in the mid 1960’s. The defendant says that the reason that it was not done earlier is that there was no pressing need for such an arrangement. It was only when very large, fast catamarans were being designed for use in rough seas that it was necessary to find a design which was both strong and light. It was only then that it became particularly attractive to use a latticework. 
25.	Mr Arnold’s first response to that is to show that the Stena design is neither necessary nor has it been used by others engaged in making large high speed catamarans in the mid-1990s. The assumption behind the Stena design is that the passenger-carrying section is incorporated into the structure of the ship in a way which involves it contributing to the solution to global forces. In other words, it is made to work as part of the strengthening of the ship. However that is not the only way of dealing with increased global forces. As both experts agree, the strengthening of the vessel can be achieved in other parts of its structure. If this is done, it is not necessary for the superstructure to participate in the global strength. If this course is adopted, the superstructure can be isolated from the rest of the vessel either by mounting it on resilient mountings or by connecting it to the rest of the vessel by means of expansion joints. If each case, the superstructure is isolated from the forces generated by hogging or sagging and plays no appreciable part in global strength. These are not merely theoretical possibilities. Resilient mounting of the superstructure was used in very large catamarans built by a company called “INCAT”. Mr Marchant gave evidence relating to this:
“The INCAT 74m “Wave Piercer” high-speed catamaran was the first large high-speed catamaran to be built. It was launched in about 1990 and was immediately the subject of much interest and comment among naval architects including myself. I cannot recall whether I read the particular report by Phil Hercus (Mr Bystedt’s exhibit SRB1) but I was by July 1992 certainly familiar with the vessel, its construction, and the problems discussed in the report via discussions I had with other naval architects and indeed with Mr Hercus. I consider that anyone designing a high speed catamaran in July 1992 would not only have known about the INCAT design but would have made it their business to learn as much about it as they could, from whatever sources. 
In the INCAT 74m design, the superstructure (ie the passenger area) is resiliently mounted on the remainder of the vessel, using rubber mountings. I understand that the main reason for doing so was to isolate the lightweight construction from the remainder of the vessel and therefore prevent the transfer of global forces. In addition, the resilient mountings would reduce the transfer of any machinery-induced vibrations. 
The main disadvantage of this technique is that the remainder of the vessel is more flexible, which in turn has to have the superstructure flexing with it. This would lead to local forces at the mountings possibly causing localised cracking. 
INCAT did find that cracking was experienced in the superstructure and that this was due to the use of resilient mountings. Accordingly they suggested (as can be seen on p. 7 of the report as exhibit SRB1) that future vessels should use a solid mounted superstructure rather than the resilient mountings. They appear to have believed that with the solid mounted superstructure, expansion joints were necessary. I do not personally believe this now, nor would I have believed it in 1992. In fact, the standard way to build high-speed catamarans before and after 1992 has been to have an integrated superstructure throughout without using any expansion joints in the superstructure or anywhere else.”
26.	Notwithstanding the fact that the cracking problem with the INCAT Wave Piercer 74 appears to have been quite severe, another, even larger, catamaran was built by INCAT using the same resilient mounting technique. It will be seen from the last quoted passage that INCAT also considered using expansion joints. In fact expansion joints were used in at least two 76 metre long catamarans made by DANYARD and called the Seajet 250. The way in which the expansion joints work was illustrated by Mr Kanstrup in his expert report. That illustration is reproduced in Annex 4. Illustrations of the Wave Piercer 74s and the Seajet 250 are to be found in Annex 5. It will be seen that both designs incorporate fairly standard runs of rectangular windows in the passenger compartment. 
27.	Mr Miller argues that the reason why INCAT used resilient mountings was that it wanted to use cheap engines which would vibrate a lot. Therefore resilient mountings would present an advantage in that they would tend to isolate the passenger compartment from vibration, as stated by Mr Marchant. Whether that was a major motive for use of this type of arrangement or not was the subject of dispute and is unclear on the evidence. In any event, I do not think it is critical to the issues I have to decide. There is no dispute that both resilient mountings and expansion joints were known ways of overcoming the global strength problem. However, the fact that there are other known and obvious ways of overcoming the problem does not mean that the design adopted by Stena is not obvious. This may be a problem to which there are a number of alternative obvious solutions. Furthermore I accept that the increase in size and speed of sea-going catamarans being built in the 1990’s means that naval architects would have had to consider ways of addressing increased global strength requirements in the vessels they were designing. To this extent I also accept Mr Miller’s argument that this is not a case of long felt want in the usual sense. There was not a pressing need to adopt the Stena-type solution, or the INCAT or DANYARD solutions at an earlier date although, as noted above, they could have been used earlier had anyone wanted to do so. 
28.	However, bracing of the type employed in Stena’s latticework beam could well have been usefully employed earlier. It is not in doubt that for very many years it was known that windows in the side of a ship could cause problems. First, there are stress concentrations at the corner of windows which can lead to fractures of the plating at this point. Furthermore, it was well known that added strength could be given to a ship by “blinding” some of the windows. The side of a ship is frequently made of a stiffened plate structure which both makes the ship seaworthy (ie it keeps water out) and makes it rigid. Placing window openings in the stiffened plate reduces that rigidity. Blinding has the effect of restoring some of the rigidity. The more windows that are blinded, the better able it is to absorb shear stresses and the more rigid the structure becomes. Blinding can transfer stresses to the adjacent windows so they have to be redesigned to distribute the forces more evenly. Illustrations of these techniques were given by Mr Kanstrup and are reproduced in Annex 6.
29.	The obvious disadvantage of blinding windows is that it renders the inside of the vessel darker. Nevertheless, as Mr Kanstrup said, use of blinded windows was very standard in ship design. It has been employed for a long time to increase the strength of sections of a ship while allowing the ship to retain the rows of vertical rectangular windows with which everyone is familiar. Instead of blinding windows it would have been possible for many years to replace them by triangular windows which would have displayed the rigidity achieved by the latticework structure. Thus, for a long time it would have been possible to achieve both increased rigidity and increased window space by using a diagonally braced structure, yet it has not been done. Mr Marchant touched on this issue in his expert report:
“I have been asked about triangular windows and whether these were known in vessels before July 1992. The precise shape of the window is normally a matter for the stylist. Any stylist would have known before July 1992 that windows could be triangular if that is the shape desired.” (para 43)
30.	This was put to him under cross-examination:
“Q. 	I was asking you about paragraph 43 in your report …Can I take it, therefore, that the direct answer to the question that you were asked is no, that triangular windows were not known before July 1992? 
A.	Known to who? 
Q. 	Known to naval architects. 
A.	I cannot believe a naval architect would not know about triangular windows. You mean the application in a boat? 
Q. 	Can you think of any examples of boats with triangular windows prior to that date? 
A.	You did not say “boats” before. I could not, no. 
Q. 	In fact, triangular windows in ships are highly unusual even now, are they not? 
A. 	I have seen them on motor yachts. 
Q. 	They are highly unusual even now, are they not? 
A.	In what context? 
Q. 	You do not see many of them. 
A.	You do not see many of them on conventional ships, no.”
31.	 Mr Marchant, or the defendant’s team, had turned their minds to the issue of whether triangular windows had been used before. Mr Marchant said that he had found one example. It was in the window section of a non-pressurised bi-plane of unknown antiquity. No one suggests that this would have been part of the common general knowledge of a naval architect or that it would have led anyone to the Stena design.
32.	The idea of using blinded windows is illustrated particularly well in another large catamaran delivered after the priority date of the patent. It is another vessel build by Austel, called the Auto Express 101. An illustration of it is to be found in Annex 7. It will be seen that large areas of the passenger compartment have been blinded. Further, as Mr Kanstrup explained under cross-examination, in that vessel the upper deck was taken down and connected to the rest of the structure so as to create very large shear areas in the nose of the catamaran, thereby helping with the solution of the stress problems. 
33.	The impression I have been left with is that at the priority date the average non-inventive naval architect designing modern ships would have acquired a mindset that windows will be rectangular. At any stage it would have been possible to use triangular windows to strengthen a part of the outer wall of a ship, but it had not been done. The fact that the strength advantages of diagonally braced structures has been known for such a long time makes it all the more notable that this is a construction technique which has not been employed in the window area of ships. The designs of the Wave Piercer 74, the Seajet 250 and the Auto Express 101 are all consistent with this standard approach to ship design. I have not been persuaded that the uninventive skilled man or team in the art at the priority date working from common general knowledge would have broken out of the conventional mindset and would have adopted the Stena solution. Mr Kanstrup was not being over generous when he described the Stena design as clever and elegant. 
Pleaded Prior Art
1.	I can now consider the other pleaded prior art. The first is the Martini patent of 1894. This is in respect of what it calls a “Compoundable ship or boat”. The main figures from the patent are reproduced in Annex 8. The top part of the ship is described as constructed “as a lattice work or as a kind of bridge truss”. This structure is designed to stiffen the ship. The ship is made in sections and can be made longer or shorter by adding or removing sections, which are bolted together. Each hull section may have two or more floatation tanks or devices, as shown, so the ship can be described as a multi-hull. When sections are to be joined together that is achieved by locking the beams together, not the floatation tanks. The ship is designed to be stored, presumably on dry ground, and to be transported from place to place. It will be seen that the bottom Figure appears to show a roof. There is no explanation in the specification of what is meant to be illustrated by this. Therefore, if it is a roof which is illustrated, there is no description of how it is attached to the sides, assuming it is not simply resting on them, nor is it disclosed whether it is meant to be solid or flexible, for example as a canvass awning would be.  
2.	Mr Miller accepts that this is a very old citation and that it would be of little interest to someone designing a high-speed aluminium vessel 80m or more in length at the priority date. However, the claims are not limited as to speed, construction material or length. He argues that, even if there is no commercial incentive to modify the Martini arrangement to make something falling within the scope of claim 3, it is technically obvious to do so. He says that anyone is entitled to take the Martini design and make something which is an obvious modification of it. 
3.	Although Mr Miller is right that one is entitled to take any piece of prior art and make obvious modifications of it, this does not mean that an alteration of a piece of prior art which is simple to achieve is obvious. In my view Martini would have been of no interest to any designer of a multihull at the priority date. It is far removed from the teaching of the Stena patent. There is no indication of the crucial box structure nor is there an arrangement in which a superstructure overlays one or more decks. It seems to me that, although it might be simple to design and build such a multi-deck arrangement, Martini offers no help in that direction. All that Martini offers is a multi-hull construction with braced girders. To turn this into something falling within the scope of claim 3 would involve more than an obvious step. It would involve a wholesale redesign, jettisoning all those features of simplicity which Martini was relying on to make his vessel easy to disassemble, move from place to place and store. Further, ignoring the need to turn this into a multi-deck vessel before it can fall within claim 3, Martini’s vessel is like a military pontoon bridge. Although it would have been possible to add windows to it, there appears to be no technical reason why that should be done. On the contrary, windows would also have added a degree of sophistication to the design which would have been inconsistent with its function. I accept Mr Arnold’s argument that adding windows would have made the apparatus heavier and less easy to disassemble and more fragile. Such a modification would have been less useful than the Martini apparatus as described. In my view this publication does not render the Stena patent obvious.
4.	The other piece of prior art relied on is the Bali Hai. This is an earlier Austal catamaran. It was of standard stiffened plate construction. As with all other vessels of the time, it had rectangular windows. It did not have the latticework structure of the Stena design. It adds nothing to the case of obviousness based on common general knowledge.
5.	For these reasons I have come to the conclusion that the invention covered by claim 3 of the patent is valid.
 Infringement
6.	A drawing of a partially sectioned side elevation of the Jonathan Swift is reproduced in Annex 9. It can be seen that the ship has triangular windows which extend from near the stern to well towards the prow. They have rounded corners and these are cut out of the stiffened plate which makes up the outer skin of the ship. A working drawing showing how the window openings are constructed is reproduced in Annex 10. Mr Arnold has provided a useful sketch which illustrates these window structures in a way which is simpler to understand. I have reproduced it at Annex 11.
7.	Mr Miller says that the row of triangular windows in the superstructure of the Jonathan Swift gives rise to a visual similarity to the design described and illustrated in the Patent. However he says that the similarity is superficial and there is no infringement. A number of arguments are advanced in relation to this. The first centres on the meaning of the words “latticework beams” in the claims. It will be recalled that claim 1 refers to; 
“latticework beams whose longitudinal profiles extend horizontally and whose planes are oriented generally vertically and in that the latticework beams are connected firmly to those walls which support the superstructure from the underlying hull”. 
Claim 2 adds; 
“the longitudinal profiles of the latticework beams are connected to the roof structure and the floor structure of the superstructure, said floor structure and said ceiling structure being constructed to contribute to the overall strength of the vessel and to strengthen the bending resistance of the longitudinal profiles of the latticework beam.”
Claim 3 incorporates all of these features. 
8.	Mr Miller says that the Jonathan Swift incorporates no latticework beams. He says that the outer wall on the superstructure is made from stiffened plate together with various channels welded to it. The only beams, properly so described, in the ship are a series of longitudinal girders located some metres inboard of the outer walls. Furthermore he says that even if a perforated and stiffened steel plate arrangement could be regarded as a beam, it is not appropriate to do so here because it does not run continuously - there are breaks in it – and it does not run the whole length of the ship. 
9.	These points can be taken in reverse order. There is nothing in the claims, nor any technical reason, which requires the beams to run the complete length of the vessel nor is there anything in the claims, nor any technical reason, which directly or indirectly prohibits them being interrupted by solid, non-perforated sections. These are not points which defeat the assertion of infringement. The more important argument is that relating to whether the structure in the Jonathan Swift can be called a beam at all. 
10.	As Mr Arnold points out, the specification indicates what it means by the words “latticework beam”. The relevant passage is set out at paragraph 17 above. It means “two essentially parallel profiled elements which are mutually joined by struts that extend generally obliquely between the profiled elements and that are inclined in alternate directions”. 
11.	There is no reason to doubt that the arrangement of reinforced openings in the side-walls of the Jonathan Swift enable its superstructure to contribute to its global strength. As the experts agree, what gives the latticework its strength is the geometry of the various parts including, in particular, the oblique struts. The way in which the structure is built is unimportant. If one considers either the detailed drawing contained in Annex 10 or Mr Arnold’s rather simpler perspective drawing in Annex 11, it can be seen that the Jonathan Swift has two essentially parallel profiled elements (i.e. the composite structures above and below the window openings) and it also has struts which extend generally obliquely between them (i.e. the window mullions). I do not accept Mr Miller’s argument that the visual similarity between the design of the superstructure in the Jonathan Swift and the patented arrangement is superficial. It is an essential part of the functional design of this part of the Jonathan Swift. In my view it falls within the meaning of “latticework beams” in the claim. 
12.	The next point taken relies on the requirement in claim 2 that “the longitudinal profiles of the latticework beams are connected to the roof structure and the floor structure of the superstructure”. Mr Miller says that this means that the latticework beam extends from ceiling to floor and is connected directly to each. He argues that this is not present in the alleged infringement because there is a fairly narrow strip of steelwork above and below the windows. In other words, instead of the windows being from floor to ceiling there is a sill below and a lintel above. In my view there is no justification for adding this restriction to the claim. With the sill and the lintel the latticework continues to add to the global strength of the ship. There is nothing in the specification which suggests that direct connection to the roof or floor is required. This point does not avoid infringement either. 
13.	The only other point of significance run by Mr Miller relates to the requirement in claim 3 that the “windows are provided in the free spaces defined by longitudinally extending profile elements and struts in the latticework beams”. His primary submission is that the claim is merely directed toward an appreciation that one can look through the free spaces which are already there in the latticework. In relation to this he notes that although the specification refers to “window glass” and the free spaces being “glazed”, there is no reference to glass or glazing in the claims. If this construction is right, this is not a point of distinction which avoids infringement but was argued to be of assistance to the argument of invalidity based on Martini. As an alternative, Mr Miller argues that if claim requires the presence of windows, then it is essential that they be located “in” the free spaces. If that is right, the Jonathan Swift does not infringe because its triangular window panes are glued to the outside of the opening in the plate structure. 
14.	In my view this is not a sensible or fair reading of claim 3. The claims and the specification are concerned with using the triangular spaces as windows. In this context a mere hole in a plate is not a window. It is an aperture. In the context of the patent, a window is a composite structure including glazing material, mullions, sills and lintels. In my view claim 3 means that the free spaces are incorporated into windows. Whether the glazing material is located in the middle of the free spaces or is attached to the outer surface makes no difference to the function of the spaces. It does no violence to the language of the claim to say that in the Jonathan Swift there are windows in the free space even though the glazing material part of the window is attached to its outer surface. 
15.	Mr Miller’s relies on claim 4 to suggest that claim 3 must be restricted to embodiments in which the glass is within the window rather than on the outer surface. I do not accept this argument. Claim 3 is not concerned with the precise position of the glazing material, whatever may have been the purpose of claim 4.
16.	For these reasons, the Jonathan Swift falls within the scope of claim 3. 
Section 60(5)(d)
1.	This brings me to consider the special provisions relating to ships contained in s 60 of the Act. The relevant subsections are set out below:
“(5) An act which, apart from this subsection, would constitute an infringement of a patent for an invention shall not do so if‑
(d) it consists of the use, exclusively for the needs of a relevant ship, of a product or process in the body of such a ship or in its machinery, tackle, apparatus or other accessories, in a case where the ship has temporarily or accidentally entered the internal or territorial waters of the United Kingdom;
(e) it consists of the use of a product or process in the body or operation of a relevant aircraft, hovercraft or vehicle which has temporarily or accidentally entered or is crossing the United Kingdom (including the air space above it and its territorial waters) or the use of accessories for such a relevant aircraft, hovercraft or vehicle;
(f) it consists of the use of an exempted aircraft which has lawfully entered or is lawfully crossing the United Kingdom as aforesaid or of the importation into the United Kingdom, or the use or storage there, of any part or accessory for such an aircraft.
(7) In this section‑
“relevant ship” and “relevant aircraft, hovercraft or vehicle” mean respectively a ship and an aircraft, hovercraft or vehicle registered in, or belonging to, any country, other than the United Kingdom, which is a party to the Convention for the Protection of Industrial Property signed at Paris on 20th March 1883; and
“exempted aircraft” means an aircraft to which section 53 of the Civil Aviation Act 1949 (aircraft exempted from seizure in respect of patent claims) applies.”
2.	In the following discussion, I will use the word “vehicle” to cover all the means of transport covered by s 60(5)(d), (e) and (f) save where it is necessary to distinguish between them. There is no dispute between the parties that making or selling a vehicle in this country does not fall within these provisions. If the vehicle or part of its equipment falls within the claims of a valid patent, it would infringe and full relief by way of damages and injunction would be available. The same would apply to a vehicle in or crossing this country, whether permanently, temporarily or accidentally if this was the country of its registration or to which it “belonged”. None of those circumstances apply here. The Jonathan Swift is a ferry. It executes between three and four return crossings between Ireland and Holyhead each day, weather permitting. Its home port is Dublin which means amongst other things that, where possible, it berths there overnight. During normal operations it will enter United Kingdom territorial waters and then remain here for about 3 hours before leaving to return to Dublin. The primary question to be answered is whether in all the circumstances, the Jonathan Swift has “temporarily … entered the … territorial waters of the United Kingdom” within the meaning of s. 60(5)(d). If it has, then it does not infringe. 
3.	Mr Arnold runs two distinct arguments against the application of the subsection. First, he says that the Jonathan Swift’s routine takes it outside the ambit of “temporarily” within the meaning of the subsection. Second, he says that the subsection does not apply to a case like this in which it is the whole ship, as opposed to a part of it, which is alleged to infringe. It is convenient to take the major issue first.
4.	Mr Arnold says that the juxtaposition of “temporarily” and “accidentally” within the subsection is of significance. He says that the former takes colour or meaning from the latter. Because of this, temporarily does not mean the reverse of permanently. It means on isolated occasions or casually. If that is so, it cannot apply to the Jonathan Swift which is regularly, frequently and persistently travelling between Dublin and Holyhead. As Mr Arnold puts it, the Jonathan Swift can be likened to a bridge with one foot at each end of its route, one in Dublin and one in Holyhead. In support of this submission he draws my attention to a number of cases in which the word “temporary” or “temporarily” has been construed in other legislation. For example in British Road Services Ltd v Wurzal [1971] 1 WLR 1508, the court was concerned with whether a trailer which was used to transport goods between the United Kingdom and the Continent on a regular basis was present here “temporarily”. This was relevant to the application of the Goods Vehicle (Plating and Testing) Regulations 1968. Lord Widgery CJ said:
“If you apply those words to the trailer in question, it is not here casually but regularly. It is here as part of its regular habits of life so far as a trailer can have such habits…
If you have here, as you have, a trailer regularly travelling between Great Britain and the Continent so that its presence in Great Britain is intermittent but regular and repeated, I do not think that it can, on a fair use of language and in particular on a true construction of this regulation, be said to be a trailer temporarily in Great Britain at any relevant time.”
5.	Mr Arnold says that, were a wider meaning, such as that advanced by Mr Miller, given to these provisions, then the Jonathan Swift would be held to be temporarily in both Irish and British waters and permanently in neither. Since Ireland has implemented equivalent provisions in s 42(d) and (e) of its Patents Act 1992, the result would be that the Jonathan Swift would be temporarily present in the territorial waters of both countries and would avoid infringement in both. Furthermore the provisions of s 60(7) mean that any well advised operator of such a ship would ensure that it was not registered in either Ireland or the United Kingdom, thereby ensuring that it would qualify as a “relevant ship” for the purpose of the legislation in both countries. The result would be that, for all practical purposes, the only place where the patentee could be sure he could enforce his rights would be in the country where the ship was being built, assuming that he has a patent there. Since, in most cases, infringement will only be discovered after the ship has been built, launched and delivered to its purchaser, there would be little chance of injunctive relief.
6.	Mr Miller says that Mr Arnold’s approach to construction is incorrect. Issues of frequency, persistence and regularity have nothing to do with whether a vehicle is “temporarily” within the jurisdiction. That word takes no colour from its juxtaposition to “accidentally”. These two words are intended to deal with unrelated activities, the former being concerned with deliberate short-term entries, the latter being concerned with unintentional entries, no matter how long they last. Further, he says that none of the authorities relied on by Mr Arnold determine the point at issue. What the word “temporarily” means must depend upon its legislative context and all of the cases relied on were concerned with very different legislation.
7.	It appears to me that Mr Miller is right in his submission that the correct starting point for an analysis of these provisions is a consideration of their legislative history. S 60(5)(d) and (e) are derived, by way of the Community Patent Convention, from the Paris Convention for the Protection of Industrial Property which, at Article 5ter provides:
“In any country of the Union the following shall not be considered as infringements of the rights of a patentee:
1.	The use on board vessels of other countries of the Union of devices forming the subject of his patent in the body of the vessel, in the machinery, tackle, gear and other accessories, when such vessels temporarily or accidentally enter the waters of the said country, provided that such devices are used there exclusively for the needs of the vessel.
2.	The use of devices forming the subject of the patent in the construction or operation of aircraft or land vehicles of other countries of the Union, or of accessories of such aircraft or land vehicles, when those aircraft or land vehicles temporarily or accidentally enter the said country.” 
8.	 Although Mr Miller has drawn my attention to a variety of documents contained within the travaux preparatoires, all except one of them throw little light on the issues I have to decide. The exception consists of a small passage in a diplomatic conference (Union Internationale pour la Protection de la Propriété Industrielle – Actes de la Conférence – Réunie a la Haye – 8 October – 6 November 1925) during which an earlier version of the proposed Article in the Convention was being considered. At that time the relevant provision referred to vessels of vehicles “penetrating” temporarily or accidentally. The Czechoslovakian delegation drew attention to the word “temporarily” and, according to the minutes, stated that it wished:
“… in particular to know whether this expression includes also regular entries – especially periodically – in which case it would prefer the use of the word “enter” rather than “penetrate”.”
9.	It appears, and Mr Arnold does not suggest otherwise, that the delegation wanted to ensure that regular and periodical entries into a country were covered by the Convention. Following this, the word “penetrate” was replaced by “enter”, as in the current version of the Convention. 
10.	In addition to this, Mr Miller has referred me to Rolltraller, a judgment of the District Court (Landgerichts) of Hamburg reported in GRUR Int. 1973 p 703. That case concerned the use of roll trailers, that is to say wheeled trailers which are connected by a coupling to a tractor unit to form a lorry. Such units can be decoupled at a port and loaded onto a container ship. That is what had happened in Rolltraller. The trailers had been loaded onto ships flying the German flag. The trailers were said to infringe a German patent. One of the issues before the court was whether the trailers themselves fell within the provisions in the German legislation equivalent to our s. 60(5)(d). The trailers were not accessories to the ships and there was no suggestion that the ships infringed any patents. The trailers were owned by a Finnish company and were used as containers for the import and export of goods from Germany. 
11.	The Landgerichts held that the non-infringement defence succeeded. In so doing it said:
“Both the wording of the law and the spirit and intention of the regulation [is] to promote the freedom of international traffic …”
12.	Further it held that the defendant’s activities fell within the statutory defence as follows:
“Any regularity and enduring repetition of the defendant’s roll trailers staying [in] the domestic territory in no way alters the fact that the roll trailers only temporarily enter the country, since after this stay they always leave domestic territory, as intended from the start, and this happened after a sufficiently short time. 
… Certainly, a stay on domestic territory can only be regarded as no longer temporary under these provisions if it lasts at least several months at one time. But this is evidently not the case in this instance – as follows from the function of roll trailers and from the speed of today’s sea transport. To this extent it is immaterial that there may constantly be roll trailers of the defendant located in domestic territory. Since the object of the patent infringement can only be the individual roll trailers, the only issue is whether the individual roll trailers are only temporarily in the domestic territory.”
13.	Consistent with the view of the Landgerichts, it seems to me that s 60(5)(d) and (e) and the Art 5ter of the Paris Convention are concerned to ensure that trade and the carriage of persons between countries is not hindered by patent rights applying to the means of transport. Whether one considers a ship, aeroplane or lorry, each is made up of large numbers of parts and accessories. Any one or more of them could be the subject of patent protection. The owner of a patent to the vehicle itself on any one of its numerous parts or accessories could immobilise the vehicle by infringement proceedings and thereby interfere with international trade or the international movement of people, at least unless and until an alternative means of transport could be put in place. Whether the means of transport takes the form of lorries, planes or ships, the underlying principle is that the normal operation of the vehicle is to be taken out of the scope of patent infringement. If the vehicle is used for an infringing purpose, then patent rights can be invoked, but not if the patent covers the fabric of the vehicle or a process which enables the vehicle to function. 
14.	Mr Miller gives a good example of the difference between these two. He says that where a ship is used for laying marine cable, that operation is not protected by s 60(5)(d) because it is not “exclusively for the needs of a relevant ship”. The cable laying is for the needs of the party which has asked for the cable to be laid. The vessel is being used for that purpose. On the other hand the propeller, bow thruster or radar equipment on a ship is used for the needs of the ship alone. They enable the vessel to perform properly and safely. 
15.	If that is correct, then s 60(5)(d) comes into play to protect the vehicle insofar as it is engaged in inter-state passage. The word “temporarily” should be construed in that context. Its primary purpose is to distinguish between vehicles which are engaged essentially in internal operations and those which travel between countries. For that reason, I accept Mr Miller’s argument, which is consistent with the decision of the Landgerichts, that questions of frequency, persistency and regularity have little to do with determining whether a vessel is temporarily within the territorial waters of the United Kingdom. Temporarily means ‘for a limited period of time’. I do not accept the attractive bridge analogy referred to above. A bridge is anchored at each end to land. It is a permanent solution to a communications or transport need. 
16.	On the other hand, I do not accept a possible extreme alternative suggestion that temporarily means the opposite of permanently. It seems to me that the section must be read to be consistent with the legislative purpose referred to above. It should be noticed that the legislation is concerned with ships and other vehicles which “enter temporarily” the territory of the State. This suggest that one has to have regard to the intention of the operator of the vehicle at the time of entry. If, at that time, it is the intention that the vehicle should move in and then move out, the entry would be temporary. Although an exact date of expected departure may not be necessary, the operator must intend that the vehicle should continue its journey by leaving the territory in reasonable time consistent with carrying out its role as a means of transport used in international carriage of goods and persons. An expectation that the vehicle may well leave the State at some time in the future, and in this sense has not entered the territory on a permanent basis, should not be enough.
17.	It is not necessary to decide what would be the position if the vehicle enters a country’s territory temporarily but, once there, the operator changes his mind although I think it unlikely that a court would construe the immunity from suit as extending to the vehicle in those circumstances. Furthermore it is not necessary to consider whether the word “enter” also connotes moving into “foreign” territory. It is possible that “enter” should be contrasted with “return”. A vehicle which returns to its operational home may not be treated the same way as one which temporarily visits foreign lands. If that is so, the Jonathan Swift would not be immune from suit in Dublin, its home port. Thus Mr Arnold’s reductio ad absurdum that the ship could not infringe anywhere (other than the place of construction) would not be true. However, since Holyhead is clearly not Jonathan Swift’s home port, this is not a point I need consider further. 
18.	Applying the above principles to the Jonathan Swift, it can only infringe when it is within our territorial waters. The issue of infringement therefore has to be looked each time it is here. Weather permitting, it does not stay in our waters for more than about three hours at a time. That is the intention of the operator, Stena. The fact that the same journey is repeated over and over again, does not alter the fact that each entry into our waters is designed to be short-lived. Indeed, the fact that it is repeated so frequently emphasises the temporary nature of its entry and the fact that it is a means of transport being used in the international carriage of goods and people. Its entry each time is temporary. 
19.	Mr Miller accepts that if this interpretation is right, it may mean that owners of patents relating to vehicles, vessels and their equipment may be forced to litigate where they are made or sold. He also accepts that, in the absence of local patent protection and a speedy application for relief, the patentee will be deprived of the opportunity to obtain injunctive relief. He says that that was the intention of the draftsmen of the Paris Convention and of our legislation. Once it is appreciated that the purpose of these provisions is to afford immunity from suit to vehicles engaged in international trade, it must follow that injunctive relief will not be available. It is injunctive relief which could prevent such trade. 
20.	This leads to Mr Arnold’s second point. He draws attention to the fact that the statutory exclusion only applies to a product (or process) “in the body” of a ship. This reads on to the exclusion of “machinery, tackle, apparatus or other accessories” on or in the ship. Taken together, these words suggest that the exclusion extends only to parts of the ship, not to the ship as a whole. Since the claims here are to a multi-hull vessel, it is the Jonathan Swift as a whole which is the infringing article. It falls outside the scope of the statutory exclusion. A similar construction would apply to s. 60(5)(e). 
21.	I do not accept this argument for four reasons. First, it is difficult to see what the logic would be in having an exclusion effective against parts but not the whole of a vessel. The point may best be illustrated by the other half of these provisions, namely the exclusion from infringement when a vessel or vehicle accidentally enters our territorial waters. If it is thought that such accidental incursions should be outwith the scope of a patent, and that such a principle should apply to parts of ships, machinery, tackle, apparatus and other accessories, it would be logical to apply the same principle to the ship as well. Mr Arnold offers no justification, other than wording, for the difference for which he contends. Second, if the purpose of this legislation is to prevent patents interfering with the means used to carry international trade, the construction suggested by Mr Arnold would undermine it. A purposive construction supports Mr Miller’s argument that these provisions apply as much to vessels and vehicles as to the parts used on them. Third, the terms of the Paris Convention are consistent with Mr Miller’s argument. The Convention, like our Act, deals with vessels, aircraft and land vehicles, but puts them into separate sub-articles. However this appears to be a matter of linguistic convenience rather than an indication of a difference in substance between the way these different modes of transport are to be treated. It will be seen that the wording of Article 5ter (1) is essentially identical to our s 60(5)(d), save that in our provision an “or” has been inserted. However Article 5ter (2) is expressed somewhat differently. In particular it excludes the “use of devices forming the subject of the patent in the construction … of aircraft”. This appears to be wide enough to cover patents relating to the way that the aircraft is constructed. By parity of reasoning, Article 5ter (1) should mean the equivalent in relation to vessels. It seems to me that our Act should be construed in a way which is consistent with the meaning of the Convention and which gives (e) and (f) similar scope.
22.	The fourth reason is somewhat narrower. If Mr Arnold is right, whether or not the exclusion is effective would be, in some cases, a matter of chance. The claims here are written in a form which covers the multi-hull vessel as a whole, but the invention is much more limited. It is not concerned with most of what goes into the vessel, such as the design of the propulsion, steering, hull, hydrodynamics, the accommodation and so forth. The inventive concept in claim 3 is the employment of the lattice work and box structure in the superstructure of the ship. The claims could have been limited to that feature. The point can be illustrated by reference to the well known patent example of the invention of a new steam whistle. Claim 1 of the patent is to the steam whistle. Claim 10 is to a container ship with a steam whistle attached to the funnel. It would make little sense if claim 1 was caught by the subsection but claim 10 was not. For this reason, even if Mr Arnold were otherwise right on this issue, I would hold that the question whether an act “consists of the use, exclusively for the needs of a relevant ship, of a product or process in the body of such a ship” should be answered purposively. In other words, is the invention the whole ship or is it for a part only. If the latter, s 60(5)(d) applies. In this case, the invention or inventive concept is not the totality of the ship but the use of the special strengthening design in part of it. 
23.	For the above reasons, I have come to the conclusion that the Jonathan Swift takes advantage of the defence available under s. 60(5)(d) and infringement proceedings cannot be used to interfere with the ferry service between Dublin and Holyhead.
24.	In the result, Stena succeed on the issue of validity but Irish Ferries succeed on the issue of infringement.