Aktiebolag & Anor v Irish Ferries Ltd.

Stena Rederi Aktiebolag and Stena Line Aktiebolag are respectively the registered proprietor of and exclusive licensee under European Patent (UK) no. 0648173 entitled “Superstructure for Multihull Vessels”. I will refer to them collectively as Stena.

Stena issued proceedings against Irish Ferries Limited (Irish Ferries) alleging infringement of the patent by use of its catamaran called the “Jonathan Swift” which sails between Dublin and Holyhead. Irish Ferries defended the proceedings. They alleged that the patent was invalid and in any case they did not infringe as the Jonathan Swift did not fall within the ambit of any claim of the patent and also because the alleged acts of infringement fell within the exception in section 60(5)(d) of the Patents Act 1977.

At the trial Stena did not seek to defend claims 1 and 2. The judge ([2002] EWHC 737 (CH); [2002] RPC 50) held that claim 3 as appendant to claims 1 and 2 was valid. He also held that the Jonathan Swift fell within those claims, but concluded that there was no infringement as section 60(5)(d) applied. The parties appeal every issue decided against them.

The Patent – The patent has a priority date of 9th July 1992. It relates to a multi-hull vessel of the catamaran type which has two or more hulls connected by means of one or more decks and an overlying superstructure.

The specification at the outset sets out the problem with which the invention is concerned. It explains that large high speed catamarans of say 100 metres in length, 12 metres high and 40 metres wide, travelling at around a speed of 40 knots, are subject to large bending and torsion stresses and also to deformation forces. Therefore the side walls of the superstructure are conventional, simple metal plates so as to form the stiffest possible side-beam structures. The specification then states that “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 those walls.” It is then explained that in conventional vessels, it is necessary to round the window openings so as to reduce the risk of stress concentrations. Even so, the elastic deformation of such window openings still remains highly troublesome and places high demands on the elastic attachment of the window panes.

Thus one object of the invention is to provide a superstructure construction which achieves a reduction in the deformation forces acting on the side walls of the passenger space, while providing the stiffened side-wall construction of the superstructure and a larger free surface for the window glass. That object is achieved by providing walls in the passenger space constructed from latticework beams. An example is described by reference to figures, two of which formed Annex I of the judge’s judgment. For convenience they are appended to this judgment as Annex I.

Figure 1 of Annex I shows a schematic cross-section of a catamaran with two hulls (2) joined by a cargo deck (3) upon which there is a superstructure (7) supported by walls (4). The superstructure is said to include passenger spaces, such as restaurants and cabins. The cargo deck (3) and the walls (4) define a cargo space for perhaps motor vehicles. As shown it is divided by bulkheads (44).

The construction of the superstructure is important. It is described in column 3 at lines 15 to 24 in this way:

“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.”

The latticework beam can be seen in Figure 2 of Annex 1, which is a sectional view of part of the superstructure. As illustrated each latticework beam (5) includes two profiled elements (51, 52) joined by struts. The beams are connected by transverse beams (55, 56).

The specification at column 2 lines 2 to 39 explains how the term shear-force absorbing latticework beams is to be understood.

“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.”

The only relevant claims are claims 1 to 4. They are in this form.

“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.

Claim 4: “A vessel according to claims 1 or 2, characterised in that a latticework beam (5) 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.”

Infringement – Section 60(5)(d) – Section 60 of the 1977 Act contains the definition of infringement. Subsection (5) provides:

“(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.”

The Jonathan Swift is a ferry registered in Eire which sails between Dublin and Holyhead 3 or 4 times a day. On each visit it is in United Kingdom territorial waters for about 3 hours.

Irish Ferries contended before the judge that section 60(5)(d) applied because the use alleged to infringe was exclusively for the needs of “a relevant ship … in a case where the ship has temporarily … entered the internal or territorial waters of the United Kingdom.”

Before the judge, Stena submitted that the routine and regular trips made by the Jonathan Swift were not such as to constitute temporarily entering territorial waters according to the appropriate construction of those words. They also submitted that in any case the subsection did not apply as the invention as claimed was the whole ship and therefore the use was not use of a product or process in the body or operation of the Jonathan Swift.

The judge rejected those submissions. When considering Stena’s first submission he drew attention to the fact that section 60(5)(d) was derived by way of the Community Patent Convention from Article 5^ter of the Paris Convention. It 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.”

Having referred to the travaux preparatoires for the Paris Convention and the judgment of the District Court of Hamburg in the Rolltraller case, reported in GRUR Int. 1973 at page 703, the judge concluded:

“73.

Consistent with the view of the Landgerichts, it seems to me that s 60(5)(d) and (e) and the Art 5^ter 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 [or] 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.

…

75.

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.

…

77.

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.

78.

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.”

He also rejected Stena’s second submission. He said:

“80.

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).

81.

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 5^ter (1) is essentially identical to our s 60(5)(d), save that in our provision an “or” has been inserted. However Article 5^ter (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 5^ter (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.

82.

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.”

I agree with the judge, but as we have had the benefit of further research and more refined argument, I will deal with the submissions of the parties.

Mr Arnold accepted that section 60(5)(d) was derived from the revision of the Paris Convention in 1925. He drew our attention to section 48 of the Patents and Designs Act 1907 and the way that that section had been amended by the Patents and Designs (Convention) Act 1928 which reproduced in substance the words of Article 5^ter. That was carried through into the 1949 Act and from there into section 60 of the 1977 Act. The amendment made by the 1928 Act, he rightly submitted, emphasised that the exception had been limited to use which was temporary or accidental only. He submitted that such a derogation from the right provided by a patent, should be construed narrowly according to the purpose envisaged by Article 5^ter.

Mr Arnold submitted that if the purpose of Article 5^ter had been to ensure that international transport was unfettered, there could have been no purpose permitting “home” country’s patents to be enforced. The purpose was, he submitted, a practical one, namely to alleviate owners of vessels from carrying out patent searches in countries where their vessels might penetrate territorial waters. It was not intended to apply to vessels which came within territorial waters on more than one occasion every day of the year like the Jonathan Swift. He submitted that the word “temporarily” should be interpreted in the same way that the Court of Criminal Appeal had interpreted that word in British Road Services v Wurzal [1971] 1 WLR 1508.

In the British Road Services case, the Court considered a case where a trailer used to transport goods between this country and the continent of Europe was found to be without a plate as required by regulation 3 of the Goods Vehicles (Plating and Testing) Regulations 1968. The defence was that the trailer was exempted by Schedule 2 of the regulations as it fell within the class of trailers “Temporarily in Great Britain a period of 12 months not having elapsed since the vehicle in question was last brought into Great Britain”.

The justices were of the opinion that the ordinary meaning of ‘temporarily’ was for a limited time. They heard nothing to the effect that the time during which the trailer had been or would be in this country was limited and therefore it followed that it ought to have been plated. They convicted the defendants.

The appeal was dismissed. Lord Widgery CJ said at page 1513:

“Mr. Slynn, for the respondent, submits that permanent is not the true or only antithesis to temporary in this context. He submits that when speaking of a vehicle being temporarily in Great Britain, one is not concerned only with the period of time for which it is expected to be there. He says that in considering whether its visit, if I may so describe it, is a temporary one, one must also consider whether such visits are paid ordinarily or regularly by the same vehicle.

It is the respondent's case that in order that the trailer may be described as being temporarily in Great Britain, one has to have regard to whether its presence was ordinary or unusual as well, the conception being that a visit constantly repeated and forming part of the regular life, as one might describe it, of the vehicle is not to be regarded as temporary merely because any individual visit is of relatively short duration.

For my part, I feel strongly that Mr. Slynn's approach is the right one. I cannot believe that in the context of these regulations the Minister intended that a vehicle should be excused from the very necessary safety precautions with which we are dealing unless it was here permanently for all time. I also think that there is implicit in the phrase 'temporarily in Great Britain' an element other than simply a time element, and I find that the language and the testing of this conception is most aptly expressed in a Scottish case on a wholly different subject but dealing with the same problem which we face today.
This is the case of Inland Revenue v. Cadwalader, (1904) 7 F. (Sess. Cas.) 146. The facts there were that an American citizen, with his ordinary residence and indeed practising the law in New York, took a three-year lease of a furnished shooting lodge in Scotland. He resided at the shooting lodge for a period of two months in each year during the shooting season, but the lodge was available to him for the rest of the year if he had wished to come. He kept his home in New York open throughout the year and returned there when he was not shooting in Scotland.

The question having arisen as to whether he was in Scotland for a temporary purpose only on those facts, Lord M'Laren says this:

“I do not think that Mr. Cadwalader is in a position to affirm, when he comes year after year during the currency of his lease to spend the shooting season in Scotland, that he is here for a temporary purpose only. I do not mean that you might not frame a definition which would bring this within the scope of temporary purposes, but, taking the ordinary meaning of the word, I should say that temporary purposes means casual purposes as distinguished from the case of a person who is here in the pursuance of his regular habits of life.”

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, and I am indebted to Lord M'Laren for that extract from his judgment because it exactly expresses what I think must really be the guiding factor in construing the words with which we are concerned.

If you have here, as you have, a trailer regularly travelling between England and the Continent so that its presence in England is intermittent but regular and repeated, I do not think that it can, on a fair use of language and in particular upon a true construction of this regulation, be said to be a trailer temporarily in Great Britain at any relevant time. I would, accordingly, dismiss the appeal.”

As the judges in that case made clear, they were interpreting the word ‘temporarily’ in the context of the particular road traffic regulations. The context of section 60(5)(d) of the Patents Act 1977, stemming as it does from the Paris Convention is very different. The Convention applies both to countries, such as the United Kingdom, which are surrounded by sea and those that are landlocked except for access by river. The purpose of Article 5^ter was to prevent national patents impinging upon foreign vessels coming into and out of territorial waters temporarily and also permanently if the cause was accidental. What States did to their own nationals was not relevant.

The judge was right in paragraph 75 of his judgment that the word ‘temporarily’ should be construed as ‘transient’ or ‘for a limited period of time’. That word cannot have been intended to be construed so that vessels which regularly went between this country and say New York or Sydney or Rotterdam would not come within the exception, but vessels who did that occasionally would do so. Whether a vessel visits temporarily, in the context of Article 5^ter, cannot depend on frequency. Support for that view comes from Anthony J. Cali v Japan Airlines Inc 380 F. Supp 1120 (1974) which was not cited to the judge. The judgment is that of District Judge Dooling. It was affirmed on appeal but that judgment has not been reported.

In the Cali case Mr Cali alleged that the defendants had infringed by the use of certain engines in flights to and from the United States. The defendants alleged that the use complained of could not be infringing because of the provisions of section 272 of the relevant statute, Article 5^ter of the Paris Convention which came into force in the US in 1962 and Article 27 of the Chicago Convention.

Section 272 so far as relevant was in these terms:

“The use of any invention in any … aircraft … of any country which affords similar privileges to … aircraft … of the United States, entering the United States temporarily or accidentally, shall not constitute infringement of any patent, if the invention is used exclusively for the needs of the … aircraft … and is not sold in or used for the manufacture of anything to be sold in or exported from the United States.”

It appears that counsel in that case may have found passages in the travaux preparatoires not provided to us as the judge said:

“Counsel have cited a passage from the record of the proceedings at the Hague Conference indicating that in a committee meeting in connection with the 1925 consideration of Article 5ter, subparagraph 2, the question of the significance of “temporarily” was brought up for discussion; the committee indicated that the words “temporarily” and “accidentally” were chosen to cover entries into port for more or less brief periods whether periodically or exceptionally and whether unintentionally or not.”

The judge continued:

“[6] The enactment of Section 272 and the adoption of Article 5ter would be incomprehensible if they were intended to cover only trivia. Their adoption implies that they were understood to create a useful immunity from infringement liability that was of enough importance to occupy the attention of the Congress and the negotiators of two treaties. Their language was chosen to deal with an internationally significant matter arising in a world in which scheduled freight and passenger services by established international carriers by air and sea were likely to require such an immunity to cover countless articles aboard aircraft or vessels that could turn out to be covered by patents in the United States that were without counterpart abroad. It is difficult to see any other purpose in Section 272 and Article 5ter than to meet the needs and realities of international trade and navigation. “Temporarily”, then, could not sensibly mean any less than entering for the purpose of completing a voyage, turning about, and continuing or commencing a new voyage. The distinction would be between a Caravelle, manufactured in France and powered with such an engine, delivered here for use by an airline in this country for domestic traffic, even though manufactured and sold in France, and a foreign aircraft arriving here on an international flight only to unload, turn about, reload and depart.”

Mr Arnold sought to distinguish the Cali case upon the ground that the defendant had relied upon Article 27 of the Chicago Convention and that the court had held that it provided a defence. That is true, but that was an additional reason for refusing to strike out the pleaded defence. If the judge had not construed the word ‘temporarily’ as he did he would have struck out the defence under Article 5^ter and that under section 272. I find the reasoning in the Cali case persuasive.

The judge in this case drew attention in paragraph 68 of his judgment to a passage in a diplomatic conference forming part of the travaux preparatoires of the Hague amendment to the Paris Convention. The Czechoslovakian Delegation is reported as bringing to the attention of the Sous-Commission the meaning of the word ‘temporarily’. The report records that the Delegation drew attention to the word ‘temporarily’ and 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”.”

The judge concluded:

“69.

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.”

We were taken to the French text which is the only official text. From that it appears that the word ‘pénétréront’ remained after the intervention of the Czechoslovakian Delegation. Thus it is not possible to come to any conclusion as to the effect of that intervention nor what was the attitude of the Sous-Commission.

The judge also relied upon the German Rolltraller decision to which I have referred. That case was decided under German Patent Law that had not been amended to give effect to Article 5^ter of the Paris Convention. That being so, it must be treated with caution. However the relevant section did exclude from the ambit of a patent equipment or vehicles entering the domestic territory only temporarily. The court said:

“72.

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.””

Support for the judge’s construction is also contained in the Guide to the application of the Paris Convention as revised in 1967 by Professor G.H.C. Bodenhausen who was the Director of the body now known as WIPO. As to Article 5^ter he said:

“There is freedom of use only if vessels enter the waters of a foreign country temporarily or accidentally. Temporary entry includes periodical entries. Accidental entry may be caused inadvertently or by shipwreck. In the latter case, the patent will not be infringed even if the presence of the vessel in the foreign water is not temporary.”

I also reject Mr Arnold’s second point for the reason given by the judge (see paragraph 18 above). The invention is that set out in the claim (see section 125). However the product of the invention is the features of the claim which are properly referred to as ‘in the body’ of the ship.

I conclude that the judge was right to decide that the defence provided by section 60(5)(d) applied and therefore there was no infringement. It is therefore not strictly necessary to decide whether the Jonathan Swift falls within claim 3 as appendant to claims 1 and 2, but in deference to the submissions of the parties I will shortly set out my reasons for concluding that the judge was right to hold that she did.

Mr Miller QC who appeared with Mr Campbell for Irish Ferries submitted first that the Jonathan Swift did not have “latticework beams” as required by claims 1 and 2. Second, he submitted that if there were latticework beams, they were not “connected to the roof structure and the floor structure of the superstructure” (see claim 2). Third, that if claim 3 required the windows to be glazed then the glazing in the Jonathan Swift was not “provided in the free spaces defined by longitudinal extending profile elements and struts” (see claim 3).

There is no dispute as to the way that the Jonathan Swift was constructed. The relevant details are shown in Annexes 9, 10 and 11 to the judge’s judgment. For convenience they are annexed to my judgment with the same numbers.

Annex 9 shows that the Jonathan Swift has a main deck, mezzanine deck, upper deck, bridge and mast deck. The claimed superstructure is the upper deck. It has triangular shaped windows formed, according to Stena, by latticework frame beams. The details of such beams are shown in Annex 10 and schematically in Annex 11.

It can be seen from Annex 10 that the triangular shape windows have rounded corners. The windows are made by cutting them out of steel plate. The alleged lattice is produced by welding channel members and struts as shown diagrammatically in Annex 11. The glazing is attached to the outside.

Irish Ferries submitted that the claim required there to be beams and that that requirement distinguished the claimed invention from a stiffened plate construction which they submitted was used in the Jonathan Swift. A beam was said to be a discrete element that resists loads. The judge was right to reject that submission. Of course there must be latticework beams, but they can be made by welding metal or cutting metal out of a sheet and welding on flanges and V-shaped channels.

The judge was also right to reject the submission that the latticework beams were not connected as required by claim 2. Admittedly, there is in the Jonathan Swift a narrow strip of steelwork above and below the windows. However that could not avoid patent infringement when the claim is construed according to the Protocol on Interpretation. There is nothing in the claim requiring direct connection.

As to the suggestion that the windows are not provided in the free spaces, the judge was right to conclude that a mere hole in a plate in the side of a ship is not a window. It is an aperture. In the context of the patent a window is a composite structure which includes glazing material. Whether the glazing is located in the middle of the aperture or attached to the outside is immaterial.

Validity – Before the judge Irish Ferries alleged that claim 3 as appendant to claim 1 of the patent was invalid as it lacked novelty and was obvious. He rejected those allegations. Before us Irish Ferries accepted that that claim was novel, but contended that it was obvious having regard to the disclosure in US Patent 522348 which I will refer to as Martini and common general knowledge.

The question of whether an invention was obvious has been called a kind of jury question. In Biogen Inc v Medeva Plc [1997] RPC 1 at 45, Lord Hoffman explained why an appellate court should be very cautious in differing from the judge’s evaluation. With that in mind Mr Miller submitted that the judge had gone wrong in principle when deciding who was the notional skilled person and also, perhaps as a result of that error, had failed to impute to him the correct common general knowledge. He also submitted that the judge’s conclusion on obviousness was plainly wrong.

As section 3 of the 1977 Act makes clear, an invention involves an inventive step if it is not obvious “to a person skilled in the art”. Such a person is, as Lord Diplock said in Catnic Components Limited v Hill and Smith Limited [1982] RPC 183 at 242, a person likely to have a practical interest in the subject matter of the invention. Mr Miller submitted that the relevant person was one that was interested in catamaran design at the priority date. From there Mr Miller submitted that such a person must have had experience in designing catamarans and therefore the judge was wrong to impute to such a person the conservatism of naval architects which had been encouraged and required by the desirability of following what are known as classification rules (see judgment paragraph 27).

Mr Arnold accepted that the specification of the patent was directed to a person who was interested in designing catamarans and in particular large catamarans where the problems referred to in the specification would be encountered. Such a person would be a naval architect not necessarily one which had previous experience of designing catamarans. As Mr Kanstrup explained Knud E. Hansen for which he worked had been approached by Stena to design a very large catamaran. If the job had been carried out he would have been in the team despite the fact that at the date he would not have designed a catamaran.

There is no evidence which suggests that naval architects generally would not have been interested in the design of catamarans and the judge was right, when considering what was the common general knowledge, to impute to the skilled person the attitude of such persons.

Mr Miller relying upon the evidence of Mr Marchant at Evidence 2 pages 215 and 216 submitted that the skilled person who was interested in catamaran design would not have the conservative attitude of naval architects. The reason being that there were no classification rules for high speed catamarans. However, he accepted that the typical naval architect, providing he had the proper training, was qualified to explore catamarans, mono-hulls and hovercraft. In these circumstances it was in my view open to the judge to hold:

“27.

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.”

Mr Miller also submitted that the judge had failed to have in mind that the use of latticework to prevent racking formed part of the common general knowledge possessed by the notional skilled person. True he did not refer to latticework beams in that context, but the criticism is misplaced as the judge held that latticework was well-known and the use to prevent racking was just one instance.

In my view there was no error of principle in the judge’s approach and therefore this Court should be slow to differ from the conclusion reached by the judge. Against that background I turn to consider the submission that his conclusion on obviousness was wrong starting first with the submissions that the invention of claim 3 was obvious having regard to the disclosure in Martini.

The disclosure in Martini is best understood from the figures in that patent which formed Annex 8 of the judgment and which is annexed to this judgment. What is shown and described is a “compoundable ship” consisting of at least two floating bodies which support a deck upon which are mounted longitudinal stiffening frames. The deck is made in sections. The construction is such that the float sections can be removed for transportation or storage of the ship. Also further sections can be inserted as shown in Figures 3 to 6. Figure 7 shows a roof but the specification does not disclose what it is made of nor how it is attached to the sides. Thus the features of claim 2 are not disclosed. Further there are no windows.

Mr Miller reminded us that the claims of the patent were not restricted to large high speed catamarans. He went on to submit that the Court had to decide whether the claimed invention was technically obvious having regard to the disclosure in Martini, not whether it was commercially obvious to make alterations.

In principle Mr Miller is right, but even so, I am convinced that the judge was right to reject the attack of obviousness based on Martini. The reasoning in paragraph 47 of the judgment is correct.

“47.

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.”

Mr Miller’s attack upon claim 3 as appendant to claims 1 and 2 starting from the common general knowledge available in 1992 had a superficial attraction. As he explained and the judge held, latticework beams were well-known before the priority date. There could not, he submitted, be anything inventive in using such beams to construct the sides of catamarans. If so, the spaces provided would naturally have been used as windows. The reason why that obvious solution had not been used before was that there had been no need until large high speed catamarans were designed at around the priority date of the patent.

Mr Miller also submitted that the evidence of both experts was only consistent with the conclusion that the invention was obvious. That submission was based upon a selective approach to the evidence. Mr Marchant accepted that naval architects could have thought the way forward was use of expansion joints, not lattice beams (Evidence 25 at page 251). He also said that once a designer goes down the route of a plated structure, he tended to stay there (Evidence 2 at page 90). That being so, it would seem that the skilled person would at least have tended to use a plated structure. Mr Kanstrup believed that the invention was clever and elegant.

It is easy once the invention is known to devise a route to the invention using steps that appear obvious. But it is important to bear in mind that the use of hindsight is unfair to inventors. The court must consider obviousness as of the priority date and without knowledge of the invention. I believe that Mr Miller’s approach has that fault. I prefer the reasoning of the judge. Mr Miller’s submissions starts from knowledge of the destination and from there he plots the course. He failed in my view to establish that the solution to the problems set out in the specification was obvious. The judge was entitled to come to the conclusion he did for the reasons he gave, in particular in paragraph 44 of his judgment.

Conclusion – For the reasons given I would dismiss the appeal and the cross-appeal.

I agree that Stena’s appeal must be dismissed for the reasons given by Lord Justice Aldous. The judge was right to conclude that section 60(5)(d) of the Patents Act 1977 provided a defence to infringement in this case.

I am less confident that the judge was right to reach the conclusion which he did in relation to validity. It seems to me that there is much force in the contention that the invention which is the subject of claim 3, as appendant to claim 1, was obvious having regard to common general knowledge in respect of the properties and use of latticework beams. But I am satisfied that the judge did not err in principle; and I am persuaded that his conclusion should be respected. I cannot say that he was plainly wrong. I, too, would dismiss the cross appeal.

I agree with my Lords that both the appeal and the cross-appeal must be dismissed and I agree entirely with the judgment and reasoning of Lord Justice Aldous. But I should like to add two observations in relation to section 60(5)(d).

The point which arises in the present case is in essence indistinguishable from that which arose in the Cali case. The only differences are that in this case the regular voyages were undertaken by sea, whereas in Cali they were undertaken by air, that the frequency of the vessel's visits in this case is somewhat greater than that of the aircraft in Cali, and that the relevant domestic legislation giving effect to the Paris Convention is in slightly different terms. That said, section 272 of the relevant federal statute incorporated in the same terms as section 60(5)(d) the crucial words taken from the Convention – "temporarily or accidentally".

The allegation in Cali was that the defendant international air carriers (Japan Airlines, KLM Royal Dutch Airlines and Scandinavian Airlines) had infringed the relevant patent "in their flights to and from the United States and their overflights of the United States in the course of the regular prosecution of their scheduled air services", which were described as being "regular, of very considerable extent, long continued and supported by ground service, marketing facilities, etc." The plaintiff's argument, in substance the same argument as that put before us by Mr Arnold, was that the words "temporarily or accidentally entering" in section 272 "cannot be taken to cover the maintenance of a regular and systematic international aircraft service to the United States".

That argument was rejected by Judge Dooling, sitting in the United States District Court in New York. I need not set out again the key passage in his judgment which has already been quoted by Lord Justice Aldous (see paragraph 30 above). I draw attention, however, to Judge Dooling's reference to the important point made in Brown v Duchesne 60 US 183 (1857) that "so to view the patent law would be to confer on the patentee the power to exact damages … where to do so would seriously embarrass the commerce of the country with foreign nations." That, as it seems to me, is a powerful argument in favour of the construction that commended itself both to Judge Dooling in Cali and – independently – to Mr Justice Laddie in the present case.

Like my Lord I find the reasoning in Cali highly persuasive. And I am glad to think that on a point arising in this area of the law, relating to international commerce, whether by sea or in the air, and founded moreover on an international Convention, the courts of this country should feel able to come to precisely the same essential conclusion as courts in Germany and the United States of America.

The other matter is this. As Lord Justice Aldous has said, whether a vessel visits temporarily cannot in this context depend on frequency. I agree. Such a test would in any event, as it seems to me, be quite unworkable in practice. On which side of the line would one put the Isle of Wight ferry, the Channel steamer crossing from Dover to Calais, the Cunarder on the North Atlantic run, the liner sailing regularly to and from the Plate or the Cape, the P&O liner on the Australia run or the supply ship making its annual voyage to St Helena or the Falkland Islands? I pose the question in terms that might have seemed appropriate to those who gathered at The Hague in 1925 to revise the Paris Convention but the same point can no doubt be formulated in more modern terms. Mr Arnold suggested that it was all a matter of fact and degree but I do him no injustice if I suggest that he had some difficulty in suggesting just where the line might be drawn. I am not at all surprised. There is no line to be drawn. The matter cannot depend on something as indefinite and imprecise as frequency.