Scottish Court of Session Decisions

Pursuer: Clark QC; Morton Fraser

Defender: Lake QC, O'Brien; Maclay Murray & Spens LLP

13 August 2013

[1] The pursuer alleges that the defender has infringed claims 1 and 15 of United Kingdom (EP) Patent No. 1 144 869 B1, and seeks declarator of the same, plus various remedies flowing therefrom. The patent relates to an invention concerning an apparatus and methods for handling drilling waste generated in offshore drilling operations. It involves a process for slurrying waste materials and drill cuttings in a tank and transferring them to other containers. At a debate, on behalf of the defender, Mr Lake, QC submitted that the pursuer does not relevantly aver any basis upon which the court could find certain integers of the claims to be present in the defender's equipment and processes. He invited the court to dismiss the action.

[2] Claim 1 of the Patent is in the following terms (with the alleged missing integers underlined):

"Apparatus for handling drill cuttings in a tank and transferring them therefrom, the apparatus comprising; pump means having a chamber, and inlet opening into said chamber, a rotatable impeller disposed in the chamber and being driven by a motor to draw drill cuttings contained in the tank into the chamber, a discharge outlet on one side of said chamber, and manipulating means operatively associated with the pump means for moving at least the inlet of the pump means vertically, horizontally, and/or laterally within the tank; wherein the manipulating means includes swivel means for orienting the pump means within the tank."

Note of argument for the defender

[3] In its note of argument, the defender describes its process as involving drilling waste being stored in a holding tank and a pump being situated beneath that tank, with the drilling waste passing into the pump by gravity and then being pumped away. The pump has two cylinders opening into a hopper. Each cylinder contains a piston. On each stroke, one piston pulls back (drawing drill cuttings from the hopper into its cylinder), and the other piston pushes forward (pushing cuttings out of its cylinder). A "swing tube" moves back and forth between the two cylinders, so that when cuttings are pushed out of a cylinder, they pass into the swing tube and are channelled away.

[4] Under reference to the pursuer's averments in article 5 of condescendence, the defender's note comments that the "inlet" in terms of claim 1 is said to be "the lower end of the swing tube" - that is to say, the end which moves back and forth between the two cylinders. The submission for the defender is that the inlet of the swing tube cannot fall within the term "inlet" as it is used in claim 1, since the "inlet" of claim 1 is an "inlet opening into said chamber" - that is, the chamber of the pump. In other words, the reference is to an inlet through which the drill cuttings pass from the tank into the pump chamber. The note states that if the pursuer's definitions of "tank" and "chamber" are accepted, then the "inlet", as the term is used in claim 1, must be the point where the hopper connects to the storage tank above. That would be the point where drill cuttings enter the chamber. However, as is plain from the pursuer's averments, the hopper is static relative to the tank, thus there are no "manipulating means ... for moving at least the inlet of the pump means ... within the tank". Accordingly the submission is that, on the pursuer's averments, it is clear that claim 1 is not infringed.

[5] The defender's note continues that, in any event, the CST unit would still lack the integer of "swivel means for orienting the pump means within the tank." The "pump means", as defined by the pursuer, is fixed in position relative to the storage tank. The pursuer relies entirely upon the motion of the swing tube. However, on the pursuer's own averments, the swing tube is merely an internal component of the pump. At best for the pursuer only the swing tube can be "swivelled and oriented" - not the pump means.

[6] Claim 15 is for:

"A method for moving drill cuttings from a holding tank to a vehicle, the method comprising the steps of locating a pump means in the tank, swivelling the pump means in the tank, and pumping the drill cuttings from an inlet in the pump means to a tank disposed on the vehicle" (alleged missing integer underlined).

The defender notes that the pursuer makes averments regarding certain processes, all of which are said to involve the CST unit. In article 6 the pursuer avers that these processes infringe claim 15 on the basis that the use of the CST unit involves the swivelling of the pump means in the tank. It can be inferred that the pursuer relies upon the same factors as those referred to as "swivel means" for the purposes of claim 1. For the same reasons the defender submits that the averments of infringement of claim 15 are irrelevant.

Note of argument for the pursuer

[7] In the note of argument for the pursuer it is maintained that the inlet of the swing tube in the defender's CST unit is to be regarded as the "inlet" referred to in claim 1. Reference is made to the averment in article 5(b) of condescendence which states that the CST unit features

"a swing tube with an inlet opening into the swing tube from either of the piston cylinders, the swing tube and cylinders forming part of the chamber of the pump means ... The CST unit thus features an inlet opening into the chamber of the pump means, within the meaning of claim 1 ..."

The note states that the defender's argument is predicated upon the assumption that the inlet referred to in claim 1 must be the means by which drill cuttings first enter any part of the chamber. That is said to be a possible, but by no means a necessary reading of the claim. The claim can be interpreted on the basis that it simply requires the inlet to admit drill cuttings to some part of the chamber - in the case of the CST unit, the swing tube. It is contended that the choice between the available readings of the claim should not be made in the absence of evidence.

[8] In relation to "manipulating means ... for moving at least the inlet of the pump means ... within the tank", the pursuer's note refers to the averment at article 5(e) of condescendence, namely that the CST unit features

"manipulating means in the form of a collar, shaft and piston which moves the inlet (the lower end of the swing tube) in an arc (ie both vertically and horizontally) within the tank. The CST unit thus features a manipulating means operatively associated with the pump means for moving at least the inlet of the pump means vertically, horizontally and/or laterally within the tank, within the meaning of claim 1 ..."

It is suggested that the defender's argument in this regard focuses on the contention that the inlet referred to in claim 1 can only be the point in the CST Unit where the hopper connects to the storage tank above it, which point admittedly does not move. The pursuer states that this issue is no more than another way of expressing the previous contention for the defender.

[9] With reference to "swivel means for orientating the pump means within the tank", reference is made to the following averred feature of the CST unit in article 5(f) of condescendence:

"Swivel means (in the form of collar and shaft, mounted so as to rotate within the hopper, which itself does not move) as part of the said manipulating means, which orient the swing tube of the pump means within the tank. The CST unit thus features manipulating means including swivel means for orienting the pump means within the tank, within the meaning of claim 1 ..."

It is not disputed that the pump means in the CST unit cannot be moved as a whole. However the note for the pursuer states that claim 1 merely requires

"manipulating means operatively associated with the pump means for moving at least the inlet of the pump means vertically, horizontally and/or laterally within the tank, wherein the manipulating means include swivel means for orienting the pump means within the tank" ( emphasis added).

[10] It is acknowledged that, after proof, the defender may succeed in satisfying the court that, on a proper construction of claim 1, the entire pump must be capable of being oriented within the tank by swivel manipulating means. However, on the pursuer's submission, a more natural reading is that the claim simply requires the inlet of the pump to be capable of such orientation.

[11] The pursuer's note of argument suggests that the issues arising under claim 15 are again no more than a restatement of the contentions put forward in respect of claim 1.

Counsel's submissions

[12] When inviting me to dismiss the action, Mr Lake took me through a number of drawings, all designed to show that it was clear that the defender's equipment and processes do not infringe the patent, and that, on the pursuer's pleadings, the action is bound to fail. In particular the pursuer has failed to aver that all of the integers of the relevant claims are present. As the discussion progressed it became apparent that, in essence, Mr Lake's proposition is that, to plead a relevant case the pursuer would need to be able to aver that the inlet to the pump in the unit moves or "swivels", so that the "pump means" can be moved around within the tank. The inlet to the pump in the defender's equipment is fixed, thus the pursuer cannot make the necessary averments. A similar submission was made in respect of claim 15. Putting the matter succinctly, Mr Lake said "Ours is fixed, the pursuer's can move about the tank." Counsel submitted that the inlet to the pump has to be an inlet to the chamber of the pump. However, in the defender's equipment, "the moving item is not the inlet to the chamber, but the inlet to the swing tube in the chamber."

[13] For the pursuer, Mr Clark, QC said that the pursuer offers to prove that the integers of the relevant claims are present in the defender's equipment and processes. An "inlet" refers to the admission of drill cuttings into any part of the chamber of the pump. An inlet is an opening which is in communication with the chamber. There is movement in the swing tube and associated change-over cylinder, all as shown on the drawings, for example production 7/12. If the patent is properly understood, this amounts to an infringement of both claims 1 and 15. Mr Clark submitted: "The inlet is simply an opening through which material can pass into part of the chamber."

[14] The pursuer intends to lead two witnesses for the purpose of allowing the court, when construing the patent, to "don the mantle of the person skilled in the art". According to Mr Clark, it would be wrong for the court to resolve the matter now, without evidence, simply on the strength of drawings produced by the defender and assertions made by counsel. Reference was made to the judgment of Aldous LJ in Monsanto & Co v Merck & Co Inc [2000] RPC 77 at pages 89/92. The court has to consider the meaning of the patent to a man skilled in the art with the knowledge of the art. An infringement can arise out of what such a person would recognise as an "obviously immaterial variant."

[15] In response, Mr Lake submitted that the pursuer must put forward sufficient pleading to justify a proof before answer on these issues. Reference was made to Lord Advocate v Johnston 1985 SLT 533 and Sutton & Co v Ciceri & Co (1890) 17 R (HL) 40, Lord Herschell at 40 and Lord Watson at 43. The pursuer does not aver any relevant common general knowledge, nor any relevant background factors in the industry. As they stand, the pursuer's pleadings are irrelevant. Reference was made to various cases, including Kirin-Amgen Inc v Hoechst Marion Roussel Ltd [2005] RPC 9 (HL); British Celanese Ltd v Courtalds Ltd (1935) 52 RPC 171 (HL); Verathon Medical (Canada) Ulc v Aircraft Medical Ltd [2011] CSOH 19; Unilever plc v Schöller Lebensmittel GmbH & Co KG [1988] FSR 596; and Conoco Speciality Products (Inc.) v Merpro Montassa Ltd 1992 SLT 444. According to Mr Lake, the words in the patent are clear. Their "obvious meaning" favours the defender.

Discussion and Decision

[16] While the interpretation of a patent is a question of law for the court to determine, as Lord Hoffman observed in Kirin-Amgen at paragraph 32, the search is for the meaning which" the notional addressee" would understand the author to have intended by the words used . His Lordship said that this is

"highly sensitive to the context of, and background to, the particular utterance. It depends not only upon the words the author has chosen, but also upon the identity of the audience he is taken to have been addressing and the knowledge and assumptions which one attributes to that audience."

It was explained that the notional addressee is the person skilled in the art, who comes to the specification with the common general knowledge of the art, reading the patent on the assumption that it is intended to describe and demarcate an invention - a practical idea. "It is this insight which lies at the heart of 'purposive construction'."

[17] This approach to the interpretation of patents necessarily means that the court should be cautious about accepting any contested invitation to reach conclusions without hearing evidence. In Verathon Medical at paragraph 31, Lord Hodge commented that the notional skilled addressee is "central" to the court's task of construing a patent. In Conoco Speciality Products, Lord Sutherland observed that, when construing a patent, the court must receive tuition from an expert skilled in the relevant art (page 448).

[18] It is well understood that any witness, expert or otherwise, should be aware of, and should not attempt to supplant the proper jurisdiction of the court. However, it is another thing to say that the court need not hear from such witnesses. In their absence, how can the court put itself into the position of the notional addressee? Construction of a patent is different from construction of a contract. In respect of the latter, usually the court needs no instruction from "a notional addressee".

[19] Mr Lake's main complaint is that there are insufficient averments to justify the proposed evidence. He notes that the only specific averment as to the knowledge of a skilled reader is in article of condescendence 5.2, and concerns unrelated topics. He submits that there is no basis on record for any departure "from the plain meaning of the words used."

[20] In the summons the pursuer has set out the case for infringement. I have quoted only a small part of those averments. The pursuer offers to prove that the notional addressee would understand the defender's swing tube mechanism to be a moveable inlet opening into the chamber of the pump as per claim 1, and involve swivelling of the pump in the tank as per claim 15. There may be cases where the ordinary meaning of the words used in a patent is so straightforward and clear that the precise basis for a contrary interpretation must be narrated in detail on record before an inquiry can be contemplated; but in my view, this is not such a case. The pursuer sets out its construction of the claims, and contends that before resolving the issues, the court should allow itself to be educated as to relevant technology and processes. Mr Clark submits that, thereafter, the proposition that the lower end of the swing tube is the "inlet" of the pump, and that it includes "manipulating" or "swivelling" characteristics within the meaning of the claims, will be easier to understand. I cannot gainsay that. And on any view, the requirements of Rule of Court 55.7 have been met.

[21] As to the provision of fair notice as to any specific aspects of technology or industry practice to be relied upon by the pursuer, I agree with Mr Clark's observation that an orderly and structured timetable for the lodging of documents, expert reports, and witness statements can avoid any potential for unfairness to the defender.

[22] Mr Lake referred to the decision of the Second Division in Lord Advocate v Johnston, but as Lord Justice Clerk Wheatley made clear towards the end of the opinion of the court, that decision turned upon its specific facts. Reference was also made to the speech of Lord Watson in Sutton & Co at page 43. Again his Lordship's comments were directed to the particular circumstances of the case, but, in so far as any generality can be taken from them, it seems to me that the pursuer has done enough to aver "the particular words to which the proof is to be directed", and, so far as might be applicable here, "the precise technical or trade meaning" to be attributed to them. Pleaders are often cautioned to avoid lengthy recitation of evidence. It would be artificial to ignore the exhibition of expert reports and witness statements (and supplementary reports and statements) in advance of the proof in commercial and intellectual property actions. This will usually ensure that no party is taken by surprise at the proof.

[23] The pursuer has averred sufficient to justify the fixing of a proof before answer (dates for which have already been reserved). I shall therefore refuse the motion for dismissal of the action, and put the case out by order for discussion of an appropriate timetable in the lead up to the proof.