Patents: construction and infringement 2003 developments

The Courts continue to seek a balance between a literal and functional interpretation of claims in accordance with the Protocol. Whilst purposive construction continues to be applied, the Courts will seek to limit claims to that which a skilled reader would be “reasonably confident” was intended by the patentee.

Scope of claim not based upon inventive contribution made – skilled reader must be “reasonably confident” variant falls within its scope.

The case of Merck v Generics (UK) provides a comprehensive review of the rules of construction and the Protocol Questions and Improver Questions - see also the case of reported in our UK Patents Reviews 2001 and 2002. Commenting upon the extensive experiments carried out for the purposes of determining the sole issue of construction, Laddie J expressed alarm both at the conduct of the litigation (see below) and the approach to determining construction adopted by the Courts - “one can stand back and think how Courts construe other documents, such as contracts, deeds and wills. It is doubtful that in any of them would it be appropriate to have expert evidence of the breadth and complexity of the evidence served here. A patent is a document written by the patentee for publication to the world at large and is designed not only to set out clearly what the invention is but to describe the monopoly sought in unambiguous terms. It is supposed to be comprehensible to members of the relevant trade simply on reading. If our law has reached the stage where experiments and extensive expert evidence is admissible to aid in construing patents, then it suggests that something has gone wrong”.

The case concerned Merck’s patented process for the production of alendronate for the treatment of osteoporosis. The Defendant also employed a process for the production of alendronate that differed in many respects from the patented process. The Claimant argued that the differences were immaterial variants that clearly were intended to be covered by the patent and thus infringed.

The Judge re-visited the fundamental principles of the drafting of patent specifications and claims - “the drafting of a specification and claim has to be considered against the background that no-one is forced to apply for a patent or to seek as wide protection as possible. The patentee can be taken to be aware of the fact that there is always a balance to be achieved between width of protection and validity. It is up to the patentee to choose the level of risk he wishes to run”. A patentee can choose language as wide or as narrow as he likes and this was stated to be particularly easy when scientific language is employed. For the patent system to work fairly, the reader of the patent must be able to understand clearly the limits of the prohibited field. He should not need to carry out experiments to determine the width of the monopoly and Laddie J directed that in future actions the Court’s informed consent to such experiments be obtained in advance (see below).

The Protocol on Interpretation of Article 69 of the Convention requires that a balance be struck combining “fair protection for the patentee” and “a reasonable degree of certainty for third parties”. The Claimant submitted that the requirement for fairness meant that the Court should give as much protection as it felt was justified having regard to the inventive contribution made by the patentee. This submission was rejected - “the Courts are not a branch of social services whose job it is to help the infirm or the unwise and the Protocol does not require them to be so. There is no cannon of construction which would justify the Courts in granting a patentee more protection than that which, objectively assessed, he indicated he wanted. Indeed, to do so would not be “fair” to the patentee. It could expose them to a greater risk of invalidity than he was prepared to shoulder”. Laddie J stated that the monopoly of a patent should only cover those embodiments, which the skilled reader would conclude, with “reasonable confidence”, the inventor wanted to cover.

Laddie J considered that the approach of “reasonable confidence” was consistent with the Improver Questions and proceeded to analyse the same. The First Improver Question, whether the variant had a material effect on the way the invention worked, was generally not in dispute. The Second Improver Question required a different test to the test of obviousness to invalidate a patent over published prior art. To invalidate a patent one merely needed to demonstrate that the skilled reader of the prior art found the prospects of achieving the desired results sufficiently encouraging to warrant trying it out. When one was attempting to broaden the patent monopoly to cover variants which were not within the contextual meaning of the claims, however, a higher degree of confidence of success must be involved - “the reader must have little or no doubt that the variant will, not may, work in the same way to produce the same results”. The Third Improver Question would be answered using the approach of “reasonable confidence” mentioned above.

On the facts, the Defendant’s process was found not to infringe whether following the direct route of the Protocol Questions or the structured approach of the Improver Questions.

Defence under section 60(5)(d) of the Patents Act 1977 that ship temporarily in jurisdiction not dependent on frequency of visits

Section 60(5)(d) of the Patents Act 1977 provides that a patent is not infringed by the use of otherwise infringing products on ships that have “temporarily” or accidentally entered the internal or territorial waters, of the United Kingdom. The Court of Appeal has upheld the first instance decision in , confirming that a defence to patent infringement based upon section 60(5)(d) of the Patents Act 1977 does not depend upon the frequency of the visits. The Defendant operated a ferry, (the “Jonathan Swift”) which sailed between Dublin and Holyhead. The Defendant’s vessel was found to comprise a super structure falling within the scope of Stena’s claims. Irish Ferries asserted that they did not infringe the patent by virtue of section 60(5)(d) of the Patents Act 1977. Stena argued that this defence was not available to Irish Ferries by virtue of the regularity and frequency of the visits of the to the United Kingdom. The Court of Appeal held that the word “temporarily” should be construed as “transient” or “for a limited period of time” and whether a vessel visited the United Kingdom temporarily could not depend on frequency. Accordingly, there was no infringement.

A device “for” a process is a device “suitable for” that process and capable of working as such for a significant part of its operation

The case of was noteworthy for a number of reasons. In the first place, Laddie J reversed an earlier finding of validity of the patent-in-suit given by himself in the case of (- see our UK Patents Review 2001 and below). In addition, a number of interesting points on construction arose.

The case concerned alleged infringement by Rockwater of Coflexip’s patent for the laying of flexible pipes and conduits on the seabed. The patent required “a tensioning means comprising the last means for guiding the flexible conduit” on board the ship. Laddie J proceeded to construe a number of these terms in order to assess the issue of infringement.

The word “comprising” was mandatory and did not equate to “capable of comprising”. The word “means”, one of the most frequently used in patent specifications, was not limited, but was used to encompass anything capable of carrying out a specified function. It thus covered any structure for guiding a flexible pipe. The term “guiding” required an element of lateral force. Laddie J cited an example discussed during the trial “if a man and woman walked down a straight road while holding hands, neither is guiding the other. If the man gently pushes the woman in a different direction, he is guiding her. He is applying a lateral force to ensure that she takes another direction. As Mr. Miller argues, if a pipe is hanging vertically in water and it passes through a hole in a plate, it is not, in that condition, being guided by the edge of the plate. Furthermore, if the pipe just touches the edge of the plate but there is no lateral force applied by the one to the other, again, , the pipe is not being guided. On the other hand, if the edge of the plate applies force to the side of the pipe so as to alter its direction, it is guiding”.

Perhaps of the most interest, however, was the Judge’s construction of the term “for”. Whilst at first instance in the case of , Laddie J had held that a “device for operating a process” meant “a device which was operating the process”. The Court of Appeal in that case disagreed with Laddie J’s interpretation and the Judge had the opportunity to follow the Court of Appeal’s construction in the present case. A means “for” guiding was thus interpreted as being a means “suitable for” guiding, and which was capable of working for a “significant” part of its operation. This is consistent with the case of (see our UK Patents Review 2001) where it was held that an apparatus “suitable” for a purpose, must be capable of being effective for that purpose.

Thus there appears to be a distinction between “product by process” claims and “product for process” claims. In the former, the process features are limiting - thus a product produced by a different process would not be infringing (see in our UK Patents Review 2003). On the other hand, with “product for process” claims, the process features are not limiting, subject to the conditions stated above. This is also consistent with the decisions in 2003 of and . In the latter case, Pumfrey J commented “that part of the claim introduced by the word “for” is merely a statement of the effect of operating the claimed process (i.e. that the process is suitable for attaining the specified result) and is descriptive rather than limiting. Such phrases rarely, if ever, operate as limitations upon the claim, and cannot normally add novelty except in the case of “Swiss-form” claims”.

Purposive construction continues to be applied

Purposive construction in accordance with the Protocol continues to be applied in the English Courts. For example, in the case of , the Court of Appeal upheld the Judge at the first instance’s construction of the term “closed”. The patent-in-suit, directed to deep-fat fryers, required the air filled space between the vessel and the skirt to be closed to prevent the escape of hot air. The Court of Appeal could not find fault with the Judge’s approach to the question of construction of the term, which needed to be construed in its context and having regard to the function which it is intended to perform - “the word “closed” is used in the claim to distinguish the prior art and to prevent the risk of burning. Both sides accept that it does not connote that there should be hermetic sealing. We are of the opinion that the Judge was right in para 27 of the Judgment to answer the question “how closed?” with the answer “closed enough practically to prevent connection between the skirt and the vessel and the consequence escape of hot air, with the associated risk of burning”. We believe that as a practical matter third parties are left in no uncertainty”.