Salts Healthcare Limited v Pelican Healthcare Limited

Lord Justice Arnold: Introduction

1. This is an appeal by the Claimant (“Salts”) against an order made by Ian Karet OBE sitting as a Deputy High Court Judge on 1 April 2025 dismissing Salts’ claim against the Defendant (“Pelican”) for infringement of UK Patent No. 2569212 entitled “An ostomy appliance” (“the Patent”), and declaring that claim 8 of the Patent was invalid as granted, for the reasons given by the judge in his judgment dated 5 March 2025 [2025] EWHC 497 (Pat) . Permission to appeal was granted on some grounds by the judge and on other grounds by myself.

2. The inventions described and claimed in the Patent concern ostomy bags, which are used to collect and store human waste emanating from a stoma, a surgically-created opening from the digestive system. The priority date of the Patent is 22 September 2017.

3. Salts contends that Pelican has infringed claims 5, 8 and 20 of the Patent by marketing its ModaVi range of ostomy bags. Pelican denies infringement and counterclaimed for revocation of the Patent. The judge held that Pelican had not infringed the Patent. Save for finding that claim 8 as granted lacked novelty over European Patent Application No. 2 229 924 (“Grum-Schwensen”), he rejected Pelican’s attacks on the validity of the Patent and he granted Salts permission to make a validating amendment to claim 8. On the appeal Salts challenges the judge’s conclusions as to infringement and lack of novelty of claim 8 as granted. Pelican has served a respondent’s notice contending that the judge’s decision on infringement should be affirmed on additional or alternative grounds, but has not cross-appealed on validity.

4. Salts commenced the claim in the Intellectual Property Enterprise Court (“IPEC”), but it was subsequently transferred to the Patents Court. In addition to the substantive issues there is an issue between the parties concerning the pre-transfer costs. The skilled person

5. It is common ground that the Patent is addressed to an engineer who develops ostomy products. The expert witnesses

6. Salts’ expert witness was Thomas Brie, whose first language is German. The judge accepted that Mr Brie had done his best to assist the court, but approached his written evidence with a degree of caution due to a concern as to his proficiency in English and therefore doubt as to whether his expert report was all his own work. Pelican’s expert witness was Birthe Andersen, whose first language is Danish. The judge found Ms Andersen a helpful witness who was trying to assist the court. Both experts had significant experience and were well qualified to give evidence on the issues. Common general knowledge

7. The parties agreed a statement of what was common general knowledge at the priority date. This included the following.

8. Ostomy appliances are made of a bag for receiving the waste and an adhesive baseplate to fix the bag to the body. The baseplate contains a central hole to accommodate the stoma. Waste enters the bag from the stoma and collects in the bottom of the bag. The top of the bag extends above the stoma creating a “headspace”.

9. The bag is typically connected to the baseplate using welding or a mechanical or adhesive coupling. Ostomy bags typically comprise two or more layers, including an internal polymer film layer which contains the waste, and an external layer of fabric to improve user comfort and reduce the noise produced by the film layer.

10. Ostomy bags may be “closed”, i.e. typically one-use products, which are thrown away once filled and replaced by the user, or “drainable”, which allows emptying and re-use. Drainable bags are often referred to as “open”.

11. Ostomy bags vary in size and volume between manufacturers, depending on the bag design and user requirements. There are three types of ostomy bags (colostomy, ileostomy and urostomy), which generally correspond to the three types of ostomy surgery. They have a variety of shapes including those shown below.

12. The diagram above shows a stoma cap (which is not a bag) at 1 and eight bag shapes at 2-9. Shape 9 is a “figure of eight” shape. Various commercial products were of this shape, such as the Convatec Esteem and the Stomocur Select.

13. Output from colostomy and ileostomy stomas varies in consistency. Colostomy waste is generally more solid than ileostomy waste. Urostomy waste is liquid. In Europe, typically a colostomate would use a closed bag and an ileostomate would use a drainable bag. A urostomate would typically use a drainable bag that also had a non-return valve to prevent urine moving back toward the stoma so as to reduce the risk of infection. Users of all three types are concerned that the bag does not fill too much to risk reflux, i.e. return through the stoma.

14. When looking to design a new type of ostomy bag, the skilled person would have looked to include features from other types of ostomy bag that were appropriate for the task, for example, the materials for the wafer. An ostomy bag manufacturer would not have liked to change the design or specification of a bag once it had been put onto the market. A user would not have liked to change the product that they were using once they had become used to fitting and using that particular design of bag.

15. The b ag shown at 9 in the diagram above has a waist, and that has an effect on how the bag will fill. The relative proportions of such a bag could be varied.

16. The parties agreed that the words “bulging” and “sagging” were not terms of art and agreed working definitions of these terms for the purposes of these proceedings as follows. “Bulging” means to swell outwards. This may be in any direction and is not limited to the direction perpendicular to the plane of the ostomy bag itself. “Sagging” means to bulge in a generally downward direction. The Patent

17. After stating at page 1 lines 9-10 that the invention relates “[i]n particular, but not exclusively” to “closed ostomy appliances”, the specification states at page 1 lines 12-19: “Ostomy appliances are well known. When an ostomy appliance becomes fuller it tends to start to bulge outwardly. Such outward bulging is unsightly, which may cause a user embarrassment. Also, the collection of waste in the bottom of the appliance can cause a user discomfort as it tends to ‘pull’ at the top of a wafer which connects the appliance to a user. This can lead to the wafer detaching, which is clearly undesirable. The present invention seeks to address these problems.”

18. After a long series of consistory clauses corresponding to the claims, the specification describes embodiments “by way of example only” by reference to seven drawings at page 11 line 21 onwards. All of the drawings depict the same embodiment.

19. Figure 1 shows a front view of an ostomy appliance of the invention. Figure 2 is a cross-sectional view of the ostomy appliance of figure 1.

20. The appliance 10 has a top 11 and a bottom 13. The specification states at page 12 lines 19-24: “The ostomy appliance 10 has first and second walls 12, 14 connected to each other at or near their peripheries 15. In the present example the first and second walls 12, 14 are welded to each other. However, they could, alternatively, be adhered to each other or connected using any other suitable means known in the art.”

21. The appliance shown is a closed ostomy appliance, but the specification explains that it could be a drainable ostomy appliance with an outlet 50 as shown by the dotted lines in figure 1. The first wall 12 includes a stoma-receiving opening 16. A connection member or flange 17 is connected to the first wall 12 for attaching the appliance to the user. A waste collecting cavity 18 is defined between the first and second walls 12, 14. The appliance may have a filter 9 over a gas vent 8 in either wall.

22. The specification states at page 13 line 18 – page 14 line 10: “Advantageously, the appliance 10 includes additional weld portions (to the peripheral weld which connects the first and second walls 12, 14 to each other). In the present embodiment, the appliance includes four such additional weld portions - two on each side of the appliance. There are weld portions 20, 28 on the left side of the appliance 10 and weld portions 22, 30 on the right side of the appliance (as viewed in figure 1). The weld portions 20 and 22 are positioned directly opposite each other, and the weld portions 28, 30 are positioned directly opposite each other. The weld portion 20 is positioned above the weld portion 28, whilst the weld portion 22 is positioned above the weld portion 30. Each weld portion 20, 22, 28, 30 extends away from the periphery 15 of the appliance 10 and downwardly towards the bottom of the appliance 10. The weld portions 20 and 22 are positioned at least partly below the stoma-receiving opening 16.”

23. It goes on at page 15 lines 4-24: “The weld portions 20, 22 , 28 , 30 are highly advantageous in preventing bulging of the appliance 10 during use when it contains waste. The weld portions 20, 22, 28, 30 ensure that the force acting on the appliance as a result of the waste is distributed relatively evenly along the length of the appliance. This helps to prevent the appliance 10 from ‘ pulling’ on the top of the connection member 17 . Each weld portion 20, 22, 28, 30 connects the first and second walls 12, 14 to each other and in this embodiment, each weld portion is a continuation of the peripheral weld which connects the first and second walls to each other. Thus, the weld portions 20, 22, 28, 30 are each connected to the peripheral weld 15 and act as an extension or continuation of the peripheral weld 15. This is advantageous because the weld portions 20, 22, 28, 30 may then be formed in the same process which forms the peripheral weld 15 between the first and second walls 12, 14. In alternative embodiments, the weld portions 20, 22, 28, 30 may not be connected to the peripheral connection 15 between the first and second walls 12, 14 e.g. there may be a space between where the first and second walls 12, 14 are not connected to each other. The weld portions 20, 22, 28, 30 are each elongate with upper edges which are generally arcuate. The weld portions 20, 22, 28, 30 could be curvilinear.”

24. Figures 3 and 4 show the weld portions 22, 30 in more detail.

25. The weld portions 22, 30 each have a top edge 22b, 30b, a bottom edge 22c, 30c and a free end 22a, 30a. The specification explains that weld portions 20, 28 are mirror images of weld portions 22, 30.

26. The specification states at page 19 lines 2-22: “As can be seen from figures 3 and 4, the weld portions 20 and 22 are a different shape from the weld portions 28 and 30. It will also be seen from those figures that the weld portions 20 and 22 are small in area (i.e. surface area of the weld) than the area of the weld portions 28 and 30. Their shapes and area size have been configured to provide improved resistance to sagging of the appliance 10 during use. As shown in figure 3, the weld portion 22 is elongate and has an axis which extends lengthways thereof substantially therethrough. The axis B is inclined at an angle (which is preferably less than 90) to an axis C which extends along the peripheral weld 15. … As shown in figure 4, the weld portion 30 is also elongate, but it will also be seen that the weld portions 30 tapers, i.e. narrows in width, as it extends away from the peripheral weld 14 downwardly towards the bottom of the appliance 10. The weld portions 30 has an axis D which extends lengthways thereof substantially therethrough. The axis D is inclined at an angle (which is preferably less than 90) to an axis E which extends along the peripheral weld 15. …”

27. The specification goes on to explain that, in some embodiments, the appliance 10 may only have one weld portion at each side. Although the specification contains further details about the specific embodiments, it does not explain what forces are acting on the appliance, or how the weld portions achieve the improvements claimed, beyond what is said at page 15 lines 4-9 (paragraph 23 above). Nor does it contain any experimental results or other evidence demonstrating the extent of the improvement achieved by the weld portions. The claims

28. Very unusually, the Patent contains no less than 10 independent claims. As noted above, Salts alleges infringement of claims 5, 8 and 20. Claim 20 is a dependent claim and can be ignored for present purposes.

29. Claim 5 may be broken down as follows: “[a] A colostomy or ileostomy appliance for receiving waste including: [b] first and second walls connected to each other at or near their peripheries, the first wall having a stoma-receiving opening; [c] a waste collecting cavity defined between the first and second walls; [d] a first weld portion positioned to one side of the appliance and which connects the first and second walls together, which first weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance; [e] a second weld portion positioned on an opposite side of the appliance to the first weld portion and which connects the first and second walls together, which second weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance; [f] a third weld portion positioned to one side of the appliance above the first weld portion and which connects the first and second walls together, which third weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance; and [g] a fourth weld portion positioned on an opposite side of the appliance to the third weld portion and which connects the first and second walls together, which fourth weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance.”

30. Claim 8 as granted may be broken down as follows: “[a] A colostomy appliance for receiving waste including: [b] first and second walls connected to each other at or near their peripheries, the first wall being provided with a stoma-receiving opening; [c] a flange or connection member positioned around the stoma-receiving opening; [d] a waste collecting cavity defined between the first and second walls; [e] a first weld portion positioned to one side of the appliance below the stoma receiving opening and which connects the first and second walls together, which first weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance; and [f] a second weld portion positioned on an opposite side of the appliance to the first weld portion below the stoma-receiving opening and which connects the first and second walls together, which second weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance.”

31. It can be seen that the principal difference between claim 5 and claim 8 is that claim 5 requires four weld portions, whereas claim 8 only requires two weld portions. In that sense claim 8 is the broader claim.

32. Claim 8 appears to be narrower in that it is limited to colostomy appliances, whereas claim 5 extends to ileostomy appliances, but neither side suggested that this difference was material. More importantly, neither claim extends to urostomy appliances. It follows that these claims are concerned with solid or semi-solid waste, and not purely liquid waste.

33. As granted, claim 8 covers both closed and drainable ostomy appliances. The judge granted Salts permission to amend claim 8 to restrict it to closed ostomy appliances in view of his finding that claim 8 as granted lacked novelty over Grum-Schwensen.

34. Although there is no allegation of infringement of any of the other independent claims, it is important to note that all of the independent claims require weld portions which extend away from a periphery of the appliance, but only some of them (claims 1, 4, 5, 8 and 11) require weld portions which extend downwardly towards a bottom of the appliance. Salts’ grounds of appeal

35. Grounds 1 and 2 are that the judge wrongly interpreted claims 5 and 8. Grounds 3 and 4 are that the judge should have held that claims 5 and 8 were infringed upon a normal interpretation of the claims. Grounds 5 and 7 concern infringement by virtue of the doctrine of equivalents. (Ground 8 was only relevant to permission to appeal, and ground 6 was not pursued.) Ground 9 is that the judge was wrong to hold that claim 8 as granted lacks novelty over Grum-Schwensen. Ground 10 concerns the pre-transfer costs. Pelican’s respondent’s notice grounds

36. Grounds 1 and 2 are that the judge interpreted the inventive concept of claims 5 and 8 too broadly. Ground 3 is that the judge was wrong to answer the first Actavis question (as to which, see below) in favour of Salts in respect of some ModaVi bags. Grounds 4 and 5 fell away when Salts’ ground 6 was not pursued. Grounds 6 and 7 provide additional reasons for the judge’s interpretation of claims 5 and 8. Appeal grounds 1 and 2 and respondent’s notice grounds 6 and 7: interpretation of the claims

37. Claims 5 and 8 both require weld portions which “extend[] away from a periphery of the appliance and downwardly towards a bottom of the appliance”.

38. The judge construed these features of the claims as follows: “59. … The requirement that the weld ‘extends away from a periphery of the appliance’ means that it is either part of or additional to the peripheral connection between the front and back of the bag. It may form part of the peripheral connection as shown in Figure 1 of the Patent or be separate.

60. The phrase ‘extends downwardly towards a bottom of the appliance’ means that the weld points down towards the bottom of the bag. The weld portions shown in the figures of the Patent all point downwards in that way.

61. Salts submit that all the Patent requires is that the welds must slope downwards in a direction that is between the horizontal and the vertical. For example, it does not matter if the periphery of the bag itself simply changes direction to achieve that effect if the result is that the waste is still directed downwards. I disagree. The description requires the weld portion - which is different from the periphery - to have a downward direction, examples of which are shown in the figures. There is also an aspect of the invention in which the welds are not required to extend downwards but are placed substantially midway down the cavity.”

39. Salts agrees with the judge’s conclusion in [59], but contends that the judge applied a different and incorrect interpretation of “extends away from a periphery of the appliance” when he came to determine infringement. Salts challenges the judge’s conclusion in [60]. The law

40. The principles of claim construction were summarised by Jacob LJ in Virgin Atlantic Airways v Premium Aircraft Interiors [2009] EWCA Civ 1062 , [2010] RPC 8 at [5] as follows (omitting two sub-paragraphs concerning the doctrine of equivalents in the light of the subsequent decision of the Supreme Court in Actavis UK Ltd v Eli Lilly & Co [2017] UKSC 48 , [2017] RPC 21 ): “(i) The first overarching principle is that contained in Art.69 of the European Patent Convention. (ii) Art.69 says that the extent of protection is determined by the claims. It goes on to say that the description and drawings shall be used to interpret the claims. In short the claims are to be construed in context. (iii) It follows that the claims are to be construed purposively—the inventor’s purpose being ascertained from the description and drawings. (iv) It further follows that the claims must not be construed as if they stood alone—the drawings and description only being used to resolve any ambiguity. Purpose is vital to the construction of claims. (v) When ascertaining the inventor’s purpose, it must be remembered that he may have several purposes depending on the level of generality of his invention. Typically, for instance, an inventor may have one, generally more than one, specific embodiment as well as a generalised concept. But there is no presumption that the patentee necessarily intended the widest possible meaning consistent with his purpose be given to the words that he used: purpose and meaning are different. (vi) Thus purpose is not the be-all and end-all. One is still at the end of the day concerned with the meaning of the language used. Hence the other extreme of the Protocol—a mere guideline—is also ruled out by Art.69 itself. It is the terms of the claims which delineate the patentee’s territory. (vii) It follows that if the patentee has included what is obviously a deliberate limitation in his claims, it must have a meaning. One cannot disregard obviously intentional elements. (viii) It also follows that where a patentee has used a word or phrase which, acontextually, might have a particular meaning (narrow or wide) it does not necessarily have that meaning in context. … (xi) Finally purposive construction leads one to eschew the kind of meticulous verbal analysis which lawyers are too often tempted by their training to indulge.”

41. As Floyd LJ explained in Adaptive Spectrum and Signal Alignment Inc v British Telecommunications plc [2014] EWCA Civ 1462 at [45]: “… It must be remembered … that the specification and claims of the patent serve different purposes. The specification describes and illustrates the invention, the claims set out the limits of the monopoly which the patentee claims. … it is conceivable that a certain, limited, meaning may be implicit in the language of a claim, if that is the meaning that it would convey to a skilled person, even if that meaning is not spelled out expressly in the language. However it is not appropriate to read limitations into the claim solely on the ground that examples in the body of the specification have this or that feature. The reason is that the patentee may have deliberately chosen to claim more broadly than the specific examples, as he is fully entitled to do.” Analysis

42. As counsel for Salts submitted, in considering the meaning of the disputed features of the claims, the starting point is to consider the purpose of the weld portions. The judge did not address this in the context of claim interpretation, although he did consider it elsewhere in his judgment (particularly at [116], quoted in paragraph 47 below).

43. The Patent states at page 15 lines 4-9 (paragraph 23 above) that the weld portions “are highly advantageous in preventing bulging of the appliance 10 during use when it contains waste”, that they “ensure that the force acting on the appliance as a result of the waste is distributed relatively evenly along the length of the appliance” and that this “helps to prevent the appliance 10 from ‘pulling’ on the top of the connection member 17”. As the judge noted, the specification does not explain precisely how the weld portions achieve this.

44. The judge summarised the evidence of the experts on this point at [50]-[51]. There was little difference between them. For the purposes of the appeal, Salts accepts the explanation given by Ms Andersen in paragraph 151 of her first report: “Output is forced up rather than out (i.e. waste is distributed more evenly along the length of the appliance, reducing irregular bulging and achieving a flatter/more uniform profile). Forcing output up limits the amount of output which can accumulate at the bottom of the bag, keeping the centre of gravity of the output closer to the user’s body, which reduces the moment of the output and the downwards force on the front of the bag, thus reducing the deformation of the top of bag (sagging). Because sagging is reduced, this in turn reduces pulling on the top of the wafer.”

45. Ms Andersen illustrated this with the following diagram showing how the weld portions reduce the usable volume of the bag and keep the waste closer to the centre line:

46. As the judge noted at [52], it is common ground that the performance of an ostomy appliance of the invention is relative. As he noted at [49] and [109], the specification provides no criterion by which to judge the extent of the improvement achieved by the invention.

47. Turning to the meaning of “extends away from a periphery of the appliance”, as noted above Salts agrees with the judge’s interpretation at [59]. Salts takes issue with what the judge said in the context of infringement at [116]: “… Each of claims 5 and 8 requires a weld portion that extends away from the periphery of the appliance. That is the actual periphery of the bag and not a hypothetical one. The purpose of the welds is to create a space within the periphery of the bag that channels the waste and also makes the bag narrower than it would be without the welds. …”

48. Salts points out that the claims are not restricted to the specific embodiments described in the Patent and should not be interpreted as if they were. Salts argues that, if the weld portion is part of the peripheral connection, and has a top edge but not a bottom edge, there is no reason why it should not be a weld portion within the meaning of the claims. Such a weld portion would still serve the purpose of redirecting the waste inside the bag given the key presence of the top edge which would narrow the bag and restrict its volume. Salts illustrates this argument with the diagram on the right below, adapted from figure 3 of the Patent, showing what Salts characterises as a top edge-only weld portion in bold which extends away from a periphery.

49. In support of this argument, Salts points out that claims 5 and 8 do not require the weld portions to have a “top edge” and a “bottom edge”, whereas claims 1, 4 and 7 do.

50. Salts is correct that this feature of the claims must be interpreted having regard to its purpose. As explained by Ms Andersen, the purpose of the weld portions extending away from the periphery is to force the waste up rather than out, and hence to keep it close to the centreline of the bag. Nevertheless, as Jacob LJ explained, purpose is not conclusive. As Lord Hoffmann said in Kirin-Amgen Inc v Hoechst Marion Roussel Ltd [2004] UKHL 46 , [2005] RPC 9 at [34], “[t]he question is always what the person skilled in the art would have understood the patentee to be using the language of the claim to mean”.

51. The distinction which Salts draws between the top edge and the bottom edge of the weld portions does not assist it. I accept that the purpose of the weld portions extending away from the periphery would appear to be served by weld portions which had a “top edge”, but not a “bottom edge” because the edge of the weld portion ran vertically downwards from the end (22a in figure 3) to rejoin the periphery (see figure 1). But the weld portion in Salts’ diagram does have a bottom edge.

52. The real question is whether, purposively construed, the language of the claims covers a weld portion constituted by a section of the peripheral weld which changes direction in the manner shown in Salts’ diagram. I agree with the judge that it does not, because it requires a “weld portion [which] extends away from a periphery of the appliance”, that is to say, an actual periphery, and not a hypothetical one (i.e. the line the peripheral weld would have followed if its direction had not changed). Salts’ interpretation amounts to re-writing the words “extends away from a periphery”.

53. As for “extends … downwardly towards a bottom of the appliance”, Salts contends that all this feature of the claims requires is that the internal upper surface of the weld portion, i.e. the top edge, slopes downwards. In support of this contention Salts relies upon common ground between the experts that the skilled reader would understand that the reason why the weld portions extend downwardly towards the bottom of the bag is in order to avoid trapping waste above the weld portions. Salts argues that the purpose of avoiding waste being trapped would be served by weld portions whose top edge slopes downwards and that the judge was wrong to interpret the claims as requiring the weld portions to point downwards.

54. Again, Salts is correct that this feature of the claims must be interpreted having regard to its purpose. Again, I accept that the purpose of the weld portions extending downwardly towards the bottom would appear to be served by weld portions with a top edge which sloped downwardly, but not a bottom edge because the edge of the weld portion ran vertically downwards from the end to rejoin the periphery. Once again, however, purpose is not conclusive. The issue here is whether, purposively construed, the language of the claims covers such a weld portion. I agree with the judge that it does not, because it requires a “weld portion [which] extends … downwardly”. Thus the weld portion as a whole must extend downwardly towards the bottom of the bag, and not merely its upper surface. Salts’ interpretation again amounts to re-writing this requirement. Pelican’s products

55. The ModaVi range includes both closed and open bags. Examples are shown below. Both versions have a peripheral weld. The red lines depict the weld portions that Salts rely upon. The closed bag (left) has both “waist” portions (marked A and B) and “lobes” (marked C and D). The open bag (right) has only a waist (A and B).

56. Further details of the products are contained in Pelican’s Product Description, the material parts of which the judge set out at [64]-[68].

57. Salts alleges infringement of both claim 5 and claim 8 by the closed bag and infringement of claim 8 by the open bag. In the case of the closed bag, Salts needs to establish that both the waist and the lobes satisfy the requirements of claim 5, but Salts can rely upon either the waist or the lobes for the purposes of claim 8. Appeal grounds 3 and 4: infringement upon a normal interpretation of the claims

58. Grounds 3 and 4 depend on grounds 1 and 2.

59. The judge held that the lobes of the closed ModaVi bag satisfied the requirements of claims 5 and 8 for weld portions that extend away from the periphery, but not the waist. Salts contends that, correctly interpreted, this feature of the claims is satisfied by the waist. Salts does not dispute the judge’s conclusion on infringement if he was right as to interpretation of this feature of the claims. This means that the open ModaVi bag does not infringe.

60. The judge held that neither the lobes nor the waist of the ModaVi products satisfied the requirement of claims 5 and 8 for weld portions that extend downwardly towards the bottom of the appliance because they extend upwardly as shown in the following diagram in Ms Andersen’s first report.

61. Again, Salts contends that, correctly interpreted, this feature of the claims is satisfied by both the lobes and the waist. Salts does not dispute the judge’s conclusion on infringement if he was right as to interpretation. Appeal grounds 5 and 7 and respondent’s notice grounds 1-3: infringement by equivalence

62. Salts does not pursue a contention that the waist “extends away from a periphery of the appliance and downwardly towards a bottom of the appliance” by virtue of equivalence. Accordingly, the only issue is whether the lobes of the closed ModaVi bag do so. As discussed below, this issue depends on the answers to three questions set out by the Supreme Court in Actavis v Lilly . The judge answered the first two questions in Salts’ favour, but the third question in Pelican’s favour. Salts contends that he reached the wrong conclusion because he wrongly identified the inventive concept of the claims (appeal ground 5) and he gave the wrong answer to the third question (appeal ground 7). Pelican contends that the judge reached the right conclusion, but that the better route to that conclusion is through the correct identification of the inventive concept (respondent’s notice grounds 1 and 2). Pelican also challenges the judge’s answer to the first Actavis question with respect to the lobes (respondent’s notice ground 3). The law

63. The Supreme Court held in Actavis v Lilly that a patent may be infringed by virtue of the doctrine of equivalents even if the product or process does not fall within the relevant claim(s) as a matter of interpretation. In order to determine this issue, Lord Neuberger said at [66] that the court should generally ask itself the following three questions: “(i) Notwithstanding that it is not within the literal meaning of the relevant claim(s) of the patent, does the variant achieve substantially the same result in substantially the same way as the invention, i.e. the inventive concept revealed by the patent? (ii) Would it be obvious to the person skilled in the art, reading the patent at the priority date, but knowing that the variant achieves substantially the same result as the invention, that it does so in substantially the same way as the invention? (iii) Would such a reader of the patent have concluded that the patentee nonetheless intended that strict compliance with the literal meaning of the relevant claim(s) of the patent was an essential requirement of the invention? In order to establish infringement in a case where there is no literal infringement, a patentee would have to establish that the answer to the first two questions was ‘yes’ and that the answer to the third question was ‘no’.”

64. The purpose of this approach is to ensure that the United Kingdom complies with the Protocol on the Interpretation of Article 69 of the European Patent Convention as amended in 2000. Article 69(1) provides: “The extent of the protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims.”

65. The Protocol states: “ Article 1 General principles Article 69 should not be interpreted as meaning that the extent of the protection conferred by a European patent is to be understood as that defined by the strict, literal meaning of the wording used in the claims, the description and drawings being employed only for the purpose of resolving an ambiguity found in the claims. Nor should it be taken to mean that the claims serve only as a guideline and that the actual protection conferred may extend to what, from a consideration of the description and drawings by a person skilled in the art, the patent proprietor has contemplated. On the contrary, it is to be interpreted as defining a position between these extremes which combines a fair protection for the patent proprietor with a reasonable degree of legal certainty for third parties. Article 2 Equivalents For the purpose of determining the extent of protection conferred by a European patent, due account shall be taken of any element which is equivalent to an element specified in the claims.”

66. Although the Actavis questions are framed by reference to the “literal” meaning of the relevant claim(s), it has since been clarified by this Court that that means the “normal” or purposive meaning: Icescape v Ice-World International [2018] EWCA Civ 2219 , [2019] FSR 5 at [60] (Lord Kitchin).

67. Question 1 is partly a question of interpretation of the specification (what is the inventive concept revealed by the patent?) and partly a question of fact (does the variant achieve substantially the same result in substantially the same way?). In so far as it is a question of fact, it is clear that the burden of proof lies on the patentee.

68. In answering question 3, it is important to note four points which Lord Neuberger made at [65]: “First, although ‘the language of the claim’ is important, consideration of the third question certainly does not exclude the specification of the patent and all the knowledge and expertise which the notional addressee is assumed to have. Secondly, the fact that the language of the claim does not on any sensible reading cover the variant is certainly not enough to justify holding that the patentee does not satisfy the third question. … Thirdly, when considering the third question, it is appropriate to ask whether the component at issue is an ‘essential’ part of the invention, but that is not the same thing as asking if it is an ‘essential’ part of the overall product or process of which the inventive concept is part. … Fourthly, when one is considering a variant which would have been obvious at the date of infringement rather than at the priority date, it is … necessary to imbue the notional addressee with rather more information than he might have had at the priority date.” Inventive concept

69. As counsel agreed, correctly answering the Actavis questions depends on the correct identification of the inventive concept. Lord Neuberger’s judgment gives little guidance as to how the inventive concept should be identified for this purpose. It seems clear, however, that the approach to identification of the inventive concept for the purposes of determining whether a claimed invention is obvious (see Pozzoli SpA v BDMO SA [2007] EWCA Civ 588 , [2007] FSR 37 at [14]-[23] (Jacob LJ)) is not necessarily appropriate for this purpose, although it may provide a starting point. Thus in Icescape Lord Kitchin focussed at [72] on the provision of the joint member as being the inventive concept of the patent since it was that feature which made the patented system different from conventional systems that formed part of the common general knowledge. By contrast, two other features of the claim were simply common general knowledge ways of implementing the inventive concept.

70. Meade J expressed the view in Formycon AG v Regeneron Pharmaceuticals Inc [2025] EWHC 2527 (Pat) at [444] that the inventive concept should be assessed at the level of generality of the claims. Neither side dissented from this, and I agree with it.

71. Meade J went on to say at [450]: “This focus on the claims and the specification in the course of answering Actavis Q1 is consistent with a number of judgments which have said that the same answer can be obtained in a given case by application of either Actavis Q1 or Actavis Q3 …. It will depend on the facts of the case but speaking for myself I think it will usually be preferable actually to answer Actavis Q1 first and in its own terms and then to bear in mind possible relevant effects of the analysis later, on Actavis Q3. Textual or drafting points which are not relevant to Actavis Q1 may come in only, or more naturally, at Actavis Q3 (for example, disclosed-but-not-claimed, not reading onto acknowledged prior art).”

72. I should explain that it is clear from the context that Meade J’s reference to “answering Actavis Q1” means identifying the inventive concept for the purpose of answering Actavis question 1. I agree with the approach articulated by Meade J. Counsel for Pelican submitted that, in the present case, considerations which the judge took into account when answering Actavis question 3 were more appropriately taken into account when identifying the inventive concept. As I will explain, I disagree with this.

73. Counsel for Pelican proposed five principles to be applied when identifying the inventive concept: (1) the starting point is the relevant claim; (2) recourse may be made to the description, but care is needed; (3) identification must be carried out with the common general knowledge in mind; (4) the inventive concept should be (relatively) easily ascertainable; and (5) the court must look at all the independent claims, not just those alleged to be infringed.

74. Counsel for Salts accepted principles (1)-(3), but took issue with principles (4) and (5). I consider that he was correct to do so. So far as principle (4) is concerned, it is of course the case that the inventive concept must be apparent from the specification. In some cases, however, it may take some working out to identify the inventive concept. As for principle (5), counsel for Pelican admitted that this was in tension with principle (1). It is the inventive concept of the claim(s) alleged to be infringed that matters, although the entire specification may throw light on what that concept is. As I will explain, the relevance of other independent claims, at least in this case, is to Actavis question 3.

75. In the present case we are concerned with the inventive concept of claim 8 since Salts only alleges infringement by equivalence in respect of the lobes. Neither side suggested that there was any material difference between claim 5 and claim 8 for this purpose, however.

76. Salts contends that the inventive concept is: “… the use of weld portions forming part of the peripheral weld in an ostomy appliance (of the type specified in each of the claims asserted), such as an ostomy pouch, in preventing bulging and/or sagging of the appliance during use when it contains waste and/or ensuring that the force acting on the appliance as a result of the waste is distributed relatively evenly along the length of the appliance.”

77. Pelican contends that the inventive concept: “… includes (at least) the following, both individually and in combination: (i) that the weld portions extend away from the periphery…; (ii) that the weld portions extend downwardly…; (iii) that the weld portion extensions achieving achieve anti-bulge functionality…; (iv) insofar as it is any different from anti-bulge functionality, that the weld portion extensions achieve anti-sag functionality; and (v) insofar as it is any different from anti-bulge functionality, that the weld portion extensions ensure that the force acting on the appliance as a result of the waste is distributed relatively evenly along the length of the appliance.…”

78. The judge concluded at [110]: “In my view the inventive concept is an ostomy appliance that has weld portions additional to the periphery of the appliance which are placed so as to minimise bulging outwards or downwards or pulling at the wafer as the bag fills in use. The welds are additional to the periphery. The inventive concept is not simply a bag of a different shape.”

79. Both parties criticise this conclusion. One of Salts’ criticisms is that the judge twice referred to the weld portions being “additional to” the periphery, when he himself had construed the claims at [59] as covering weld portions which are “either part of or additional to the peripheral connection”. As Pelican submits, this is a purely semantic point. It can be seen that, in context, what the judge meant at [59] was that the weld portions may be either connected to or separate from the peripheral connection (as explained in the specification at page 15 lines 11-21, quoted in paragraph 23 above). What he meant at [110] was that, either way, the weld portions are additional to the peripheral connection and not merely a section of it.

80. Salts’ principal argument is that the judge’s formulation fails to reflect what Salts characterises as the broader teaching of the specification at page 15 lines 4-9. Pelican ripostes that that passage is not a broad teaching, but a limited teaching about the specific weld portions 20, 22, 28, 30 disclosed in the embodiment depicted in the figures.

81. Pelican’s principal argument is that the judge’s formulation ignores the structural features of the weld portions, namely that they extend away from the periphery and downwardly. Pelican says that the invention is defined in structural terms, not functional terms, and this should be reflected in the inventive concept. Salts ripostes that Pelican’s formulation is tantamount to limiting the inventive concept to the wording of the claims.

82. In considering these arguments it is convenient to begin with two points that are common ground. The first is that the inventive concept concerns the provision of the weld portions, and has nothing to with the remaining features of an ostomy appliance. The second is that the inventive concept should reflect the function of the weld portions as it would be understood by the skilled reader of the specification, and specifically the function of the weld portions in the context of claim 8.

83. As discussed above, it is common ground that the skilled reader would understand that the function of the weld portions is to force waste up rather than out, so that the waste is distributed more evenly along the length of the bag, thereby reducing bulging and sagging. It is also common ground the skilled reader would also understand that the weld portions should be shaped so as to avoid trapping waste above them.

84. There are two problems with Salts’ formulation of the inventive concept. The first is that it extends to “weld portions forming part of the peripheral weld”. As the judge evidently recognised, even though he did not articulate the point, this is too broad. There is nothing in the specification to suggest that the weld portions may be constituted by a section of the peripheral weld. All the teaching is of weld portions which are additional to the peripheral connection. Furthermore, this formulation appears to cover the common general knowledge “figure of 8” bags. (Counsel for Salts submitted that this point was not open to Pelican because Pelican had not pleaded that claim 8 was invalid over common general knowledge, but I disagree: the issue here is one of formulation of the inventive concept for the purposes of determining the scope of protection of claim 8.) The second problem is that the formulation fails to reflect the second purpose mentioned in paragraph 83 above.

85. Turning to Pelican’s formulation of the inventive concept, I agree with Salts that it is too tied to the language of the claims. It is correct that claim 8 is expressed in structural, not functional, terms, but in a case such as this the issue which the Actavis questions are intended to enable the court to decide is whether the scope of protection of the claim is limited to the precise description of the structures in the claim. Accordingly, the answer to the enquiry should not be pre-empted by the formulation of the inventive concept if that can be avoided. In some cases, such as cases involving chemical formulae, it may be unavoidable.

86. Accordingly, I would characterise the inventive concept of claim 8 as follows. It is the provision in an ostomy appliance of weld portions additional to the peripheral connection (in the sense explained in paragraph 79 above) which are positioned and shaped (i) so as to force waste up rather than out, so that the waste is distributed more evenly along the length of the bag, thereby reducing bulging and sagging, and (ii) so as to avoid trapping waste above them. Question 1

87. The judge answered question 1 in the affirmative for reasons he expressed as follows: “125. The question with respect to the lobes of the ModaVi bag is not easy to determine from the experiments. The lobes do appear to have some impact on the way the bag expands and holds its shape, although the effect on bulging appears small - there does appear to be some more regularity in Pelican’s experimental Mod B bag with lobes as compared with the bags without, and it appears clear that the lobes do have the effect of making the peripheral weld point away from the body. That is in line with the description in Eakin.

126. … The lobes extend inward of the periphery of the ModaVi bag and away from a periphery of the appliance. While they do not extend downwards, the experiments and Eakin show that they do affect the shape of the bag so as to minimise bulging outwards or downwards or pulling at the wafer as the bag fills in use. The answer is for the lobes is ‘yes’.”

88. The experiments referred to in this passage are experiments conducted by the parties for the purposes of the litigation, some of which the judge considered at [72]-[89]. As one would expect, the expert witnesses gave evidence about what conclusions could be drawn from these experiments which the judge assessed. “Eakin” is International Patent Application No. WO 2021/165703 filed by Pelican to protect the design of its ModaVi bags, which the judge considered at [91]-[96]. Salts also relied upon a presentation used by Pelican to launch the ModaVi range, which the judge considered at [97]-[99].

89. Pelican contends that the judge’s conclusion in [126] is wrong. On the face of it, this is a challenge to a finding of fact and therefore Pelican must demonstrate that it is rationally insupportable ( Volpi v Volpi [2022] EWCA Civ 464 , [2022] 4 WLR 48 at [2](v) (Lewison LJ)). Given that it was based in large part upon on the judge’s assessment of the experimental and expert evidence, Pelican has a formidable hurdle to overcome. Counsel for Pelican sought to avoid this difficulty by arguing that Pelican did not challenge the judge’s assessment of the evidence, but only his findings as to how the bags worked. I do not consider that this is tenable distinction. The judge found as a fact how the ModaVi bags worked, based upon his assessment of the evidence. In reality, this is an attack on the judge’s assessment of the evidence. Counsel for Pelican did not go so far as to submit that the judge’s finding was rationally insupportable, and counsel’s submissions were a classic exercise in “island-hopping” through the evidence. Not having been taken through all of the relevant evidence which the judge was immersed in, I do not consider that this Court is in a position to question his finding.

90. It can be seen that the judge’s finding does not address the question of whether the lobes are shaped so as to avoid trapping waste above them. Pelican contends that they are not, and that this Court is not in a position to make a finding on this question. In my judgment it is plain that the lobes are shaped so as to avoid trapping waste above them. Question 2

91. It is not in dispute that, if question 1 is to be answered “yes”, then so is question 2. Question 3

92. The judge answered this question “yes” for reasons he expressed at [129] as follows: “… The invention can be achieved in a number of ways, for example, as Salts [ sic – this should be Pelican] put it in closing, by making a narrower bag. In this case the patentee has chosen a particular way in which to achieve the intended effect and has limited the claims to the specific structures claimed. The Patent describes a set of appliances that have particular features. It would, for example, have been straightforward for the patentee to formulate a claim by result or to a ‘narrower’ bag or to omit the word ‘downwardly’, but none of the asserted claims does that. The claims are limited to appliances with the particular structures claimed and strict compliance is intended.”

93. Salts contends that this reasoning is flawed and that the judge reached the wrong conclusion. Pelican supports the judge’s conclusion and offers additional reasons for it.

94. For the reasons explained above, the variant under consideration at this stage is the lobes. The judge held that the lobes extend away from the periphery of the closed bag, but not downwardly towards the bottom of the bag. Rather, they extend upwardly. Thus the critical question is whether the skilled reader would understand that strict compliance with that feature of claim 8 was required.

95. There was some discussion during the course of argument as to how this question should be approached. Although there were some references to burden of proof, this is not a factual issue on which either party has a burden of proof. It is a question of interpretation of the specification. It is clear from Lord Neuberger’s formulation of the question, and in particular his use of the word “nonetheless”, that there must be a good reason why the skilled reader would conclude that strict compliance was required even though the answers to the first two questions are “yes”.

96. As counsel for Salts submitted, it is clear from Actavis that the wording of the claims can rarely, if ever, provide a good reason in itself. The fact that the variant does not fall within the normal meaning of the claims is the starting point for the enquiry, not the end of it.

97. In my judgment the judge gave the correct answer to question 3 for four cumulative reasons.

98. First, I agree with Pelican and the judge that the skilled reader would consider it significant that claim 8 is formulated in structural and not functional terms. Furthermore, the structural requirements are prescribed with considerable specificity.

99. Secondly, I agree with Pelican that the skilled reader would consider it significant that the functional improvements claimed in the specification at page 15 lines 4-9 (paragraph 23 above) and page 19 lines 5-7 (paragraph 26 above) are only claimed for the specific weld portions 20, 22, 28, 30. The specification does not disclose any general principle. This appears to explain why the claims are closely modelled on the specific embodiments.

100. Thirdly, I agree with Pelican that the skilled reader would consider it significant that there are a large number of independent claims. This suggests that the patentee has carefully considered the extent to which the scope of the claims should extend beyond the specific embodiments and has attempted to cast the claims as broadly as possible.

101. Fourthly, I agree with Pelican that the skilled reader would consider it significant that claim 8 is limited to weld portions which extend downwardly towards a bottom of the appliance, whereas this is not a feature of other independent claims. This is a strong case of the principle that what is disclosed in the specification, but not claimed, is disclaimed (see Akebia Therapeutics Inc v Fibrogen, Inc [2020] EWHC 866 (Pat) , [2020] RPC 15 at [453]-[454]).

102. Accordingly, I consider that extending the scope of protection of claim 8 in the manner contended for by Salts would go beyond fair protection for the patentee and would not afford a reasonable degree of legal certainty for third parties.

103. I therefore conclude that the judge was correct to hold that the closed ModaVi bag does not infringe claim 8. Grum-Schwensen

104. Grum-Schwensen discloses a drainable ostomy pouch with a comfort layer and a releasable, sealable fold-up closure system. The specification explains at [0010] that the fold-up outlet portion is hidden behind the comfort layer, making the pouch more ergonomic to wear. The drainable pouch also has what [0016] describes as “inwardly extending welding portions” on each side of the pouch “above the outlet portion”.

105. Figures 1 and 2 depict a first embodiment described at [0019]-[0024].

106. The pouch has side walls 1 and 2 joined by peripheral weld 7. Comfort layer 3 on the distal (external) side of the pouch (hatched with crosses) covers the main portion of the pouch. An extension 9 to the comfort layer (hatched with dots and crosses) covers the top of the outlet portion 4 of the bag. A comfort layer 3a may also be provided on the proximal (body) side of the pouch. The proximal side of side wall 1 is provided with a first fastener strip 5. The inside surface of extension 9 is provided with a second fastener strip 6. Welding portions 8 are said at [0023] to “define the passage between the cavity of the pouch and the outlet section of the pouch”. Also visible are “bias members” 10 and 11.

107. Figure 2 shows a solid block above second fastener strip 6 which is not identified in the description. It can be seen approximately to correlate with the position of welding portions 8, except that it is depicted on the distal face of wall 2 rather than between walls 1 and 2.

108. Figures 3 and 4 depict a second embodiment described at [0025]-[0027].

109. In this embodiment extension 9 is provided as a separate part (hatched with dots) which may be attached to the pouch by the welding portions 8. In addition, a separate welding 12 may be provided for attaching extension 9 to side wall 2. Curiously, welding portions 8 are not shown in Figure 4.

110. The way in which the outlet portion folds up is shown in Figures 5-8.

111. Figure 5 shows the outlet section unfolded. Figure 6 shows a first fold, Figure 7 a second fold and Figure 8 a third fold. In Figures 7 and 8 the folded-up outlet section is tucked first partially and then fully under the extension 9 of the comfort layer 3. In Figure 8 the fastening strips 5 and 6 are adhered to each other.

112. It can be seen from Figure 5 that welding portions 8 are indicated by the solid block. As in Figure 1, the solid block is located on the distal face of wall 2 rather than between walls 1 and 2. The same solid block can be seen in Figures 6, 7 and 8. In Figures 5, 6 and 7 there is a gap between walls 1 and 2 of the outlet portion, but no such gap is shown in Figure 8. Appeal ground 9: novelty The law

113. The judge said at [131] that there was no dispute as to the applicable law, but he did not set out the legal test for novelty. It is evident from the submissions made to this Court that he did not receive as much assistance on this question as he should have done.

114. A patent claim lacks novelty if there is a prior disclosure of something within the claim which is enabled. For present purposes the requirement of enablement can be ignored. The test for prior disclosure was authoritatively stated by Lord Hoffmann in SmithKline Beecham Plc’s (Paroxetine Methanesulfonate) Patent [2005] UKHL 59 , [2006] RPC 10 at [22]: “… the matter relied upon as prior art must disclose subject-matter which, if performed, would necessarily result in an infringement of the patent. That may be because the prior art discloses the same invention. In that case there will be no question that performance of the earlier invention would infringe and usually it will be apparent to someone who is aware of both the prior art and the patent that it will do so. But patent infringement does not require that one should be aware that one is infringing …. It follows that, whether or not it would be apparent to anyone at the time, whenever subject-matter described in the prior disclosure is capable of being performed and is such that, if performed, it must result in the patent being infringed, the disclosure condition is satisfied. The flag has been planted, even though the author or maker of the prior art was not aware that he was doing so.”

115. Prior disclosure is a strict test. It requires either clear and unambiguous disclosure in the prior document (often referred to as “explicit disclosure”), or clear and unmistakable directions to do something which in fact falls within the claim (often referred to as “inevitable result”): see General Tire v Firestone Tyre and Rubber Co [1971] FSR 417 at 443-444. It is not sufficient that it would be obvious to carry out or modify the prior art in a manner which falls inside the claim. Nor is it sufficient that putting the prior art into practice would be more likely than not to result in something falling within the claim. Standard of review

116. Explicit disclosure is a bright-line test which depends on the application of the correct legal standard to the prior art. The interpretation of the prior art is a question of law once the court has been properly instructed by the expert evidence as to the common general knowledge with which the skilled person reads the document, and hence the technical considerations which bear upon its interpretation. It follows that there is a right answer to any question of explicit disclosure. It is not a matter of evaluation taking into account multiple factors and applying an imprecise standard, like obviousness.

117. Although inevitable result involves a factual question, it is necessary to bear in mind the strict standard which must be applied. Unlike most factual questions, a finding on the balance of probabilities is not sufficient. Assessment

118. There is no dispute that Grum-Schwensen discloses all of the features of claim 5 except for weld portions which “extend away from a periphery of the appliance and downwardly towards a bottom of the appliance”. Salts accepts that Grum-Schwensen discloses weld portions, but contends that they create an aperture in the bottom of the bag through which waste may flow into the outlet portion and out of the bag when the outlet portion is unfolded. Pelican contends that the weld portions are above the bottom of the bag and thus extend away from the periphery and downwardly towards the bottom of the bag. Thus the issue depends on the location of the bottom of the bag when the outlet portion is folded up.

119. The judge said at [138]: “The experts disagreed over where the bottom of the bag would be when the drain was folded up. Ms Andersen said that when the drain was folded waste would still enter the top of the fold and move down to the point at which the two sides of the bag were held directly together. Mr Brie said that the closure would form at the level of the weld portions. Having heard the experts, I prefer Ms Andersen’s explanation, which she illustrated in her reports as shown below … in which the finger is shown in red. The waste would collect below the weld portions when the bag was closed. That forms the bottom of the bag for these purposes. ”

120. The upper diagram (Figure F in Ms Andersen’s second report) is based on Figure 9 of Grum-Schwensen, which depicts the drainable pouch from the proximal (body) side. (Figure 9 has the advantage of not showing the extension 9 of the comfort layer 3, which obscures the area in question in Figures 1 and 3.) Ms Andersen explained in paragraph 43 that she had “added a red line indicating more or less where the bottom of the bag will be”.

121. The lower diagram (Figure C in M Andersen’s first report) is based on Figure 8 of Grum-Schwensen. Ms Andersen explained in paragraph 84 that “[t]he region of usable volume between the side walls (1)(2) is indicated by the green line, which terminates at the fold”. In addition to the green line, Ms Andersen has added two annotations indicating the positions of welding portions 8 and 12 respectively. These annotations are inaccurate. As explained above, the solid block in Figure 8 denotes welding portions 8. Welding portion 12 is not shown in Figure 8.

122. Salts contends that, not merely is there is no clear and unambiguous disclosure in Grum-Schwensen that the bottom of the bag is located at the point shown by the red line in Ms Andersen’s Figure F, nor is it an inevitable result of putting Grum-Schwensen into practice, but this is positively wrong.

123. Figure F shows the outlet portion unfolded, as in Figures 1 and 3. Ms Andersen has drawn the red line at the level of fastener 5. It can be seen from Figures 2 and 4 that fastener 6 is higher upon than fastener 5 (more so in Figure 2). When the outlet portion is folded up, it can be seen from Figure 8 that fasteners 5 and 6 are aligned and adhered to each other. Salts argues that it follows that the location of the bottom of the bag when folded must be as shown by the green line in the diagram below rather than as shown by the red line.

124. Salts also argues this reading of Grum-Schwensen is supported by: (i) the language of [23] quoted in paragraph 106 above; and (ii) the absence of the gap between the walls 1 and 2 in Figure 8, and the contrast with the gap shown in Figures 5-7.

125. Counsel for Pelican had little answer to these arguments other than to point out the figures in Grum-Schwensen are schematic. That is correct, but it does not assist Pelican.

126. In my judgment it cannot be said that Grum-Schwensen clearly and unmistakably discloses that the bottom of the bag when the outlet portion is folded up is in the position contended for by Pelican. Due to the schematic nature of the figures, and the fact that welding portions 8 seem to be shown in the wrong places in Figures 1 and 5-8, it is impossible to be sure where the bottom of the bag is. If anything, I consider that Salts’ interpretation of the document is more persuasive.

127. Turning to inevitable result, the judge said that he preferred Ms Andersen’s explanation to that of Mr Brie, but he gave no reason for this and did not attempt to reconcile Ms Andersen’s evidence with the disclosure of the document. Counsel for Pelican submitted that Mr Brie had accepted Ms Andersen’s explanation in cross-examination, but there are three problems with that submission. First, the judge made no such finding. Secondly, it is not clear to me from the passage of transcript relied upon that Mr Brie did accept Ms Andersen’s explanation, particularly given that counsel for Pelican did not put Ms Andersen’s Figure C to Mr Brie. Thirdly, it appears from her oral evidence that Ms Andersen based her interpretation on her experience of commercial ostomy bags which she understood to embody the invention claimed in Grum-Schwensen, but such bags are neither an admissible aid to interpretation of the document nor proof of the inevitable result of putting it into practice. In any event, the judge made no finding that it would be an inevitable result of putting of Grum-Schwensen into practice that the bottom of the bag would be in the location identified by Ms Andersen, and Pelican has not contended by way of its respondent’s notice that the judge should have made such a finding upon the evidence.

128. I therefore conclude that Pelican has not demonstrated that claim 8 as granted lacks novelty over Grum-Schwensen, and that Salts’ appeal on this ground should be allowed. Appeal ground 10: pre-transfer costs

129. IPEC has a unique costs regime. In order to understand the issue raised by this ground of appeal, it is first necessary to set out the relevant provisions of the CPR before explaining what happened in this case. The relevant CPR provisions

130. Rule 63.18(2) provides: “When considering whether to transfer proceedings to or from the Intellectual Property Enterprise Court, the court will have regard to the provisions of Practice Direction 30.”

131. Paragraph 9.1 and 9.2 of Practice Direction 30 provide: “9.1 When deciding whether to order a transfer of proceedings to or from the Intellectual Property Enterprise Court the court will consider whether – (1) a party can only afford to bring or defend the claim in the Intellectual Property Enterprise Court; and (2) the claim is appropriate to be determined by the Intellectual Property Enterprise Court having regard in particular to – (a) the value of the claim (including the value of an injunction); (b) the complexity of the issues; and (c) the estimated length of the trial. 9.2 Where the court orders proceedings to be transferred to or from the Intellectual Property Enterprise Court it may – (1) specify terms for such a transfer; and (2) award reduced or no costs where it allows the claimant to withdraw the claim .”

132. Rule 63.26 provides: “(1) Subject to paragraph (2), the court will reserve the costs of an application to the conclusion of the trial when they will be subject to summary assessment. (2) Where a party has behaved unreasonably the court may make an order for costs at the conclusion of the hearing. (3) Where the court makes a summary assessment of costs, it will do so in accordance with Section VII of Part 46.”

133. Section VII, “Scale costs for claims in the Intellectual Property Enterprise Court”, of Part 46 contains the following rules: “46.20 Scope and interpretation (1) Subject to paragraph (2), this Section applies to proceedings in the Intellectual Property Enterprise Court. (2) This Section does not apply where— (a) the court considers that a party has behaved in a manner which amounts to an abuse of the court’s process; or (b) the claim concerns the infringement or revocation of a patent or registered design or registered trade mark the validity of which has been certified by a court or by the Comptroller-General of Patents, Designs and Trade Marks in earlier proceedings. (3) The court will make a summary assessment of the costs of the party in whose favour any order for costs is made. Rules 44.2(8), 44.7(b) and Part 47 do not apply to this Section. (4) ‘Scale costs’ means the costs set out in Table A and Table B of the Practice Direction supplementing this Part. 46.21 Amount of scale costs (1) Subject to rule 46.22, the court will not order a party to pay total costs of more than— (a) £60,000 on the final determination of a claim in relation to liability; and (b) £30,000 on an inquiry as to damages or account of profits. (2) The amounts in paragraph (1) apply after the court has applied the provision on set off in accordance with rule 44.12(a). (3) The maximum amount of scale costs that the court will award for each stage of the claim is set out in Practice Direction 46. (4) The amount of the scale costs awarded by the court in accordance with paragraph (3) will depend on the nature and complexity of the claim. (5) Subject to assessment where appropriate, the following may be recovered in addition to the amount of the scale costs set out in Practice Direction 46 – Costs – Special Cases— (a) court fees; (b) costs relating to the enforcement of any court order; and (c) wasted costs. (6) Where appropriate, VAT may be recovered in addition to the amount of the scale costs and any reference in this Section to scale costs is a reference to those costs net of any such VAT. 46.22 Summary assessment of the costs of an application where a party has behaved unreasonably Costs awarded to a party under rule 63.26(2) are in addition to the total costs that may be awarded to that party under rule 46.21.”

134. Practice Direction 46 sets out costs limits for each stage of the proceedings, but it is not necessary to set these out. The order for transfer

135. As explained above, Salts commenced this claim in IPEC. On 24 May 2023 Pelican applied to transfer the claim to the Patents Court. On 11 July 2023 HHJ Hacon acceded to Pelican’s application and made an order for transfer for the reasons he gave in his judgment of that date [2023] EWHC 2232 (IPEC) .

136. Pelican made the following submission in paragraph 32 of its skeleton argument for that hearing: “It is submitted that pre-transfer costs ought not to be confined to the IPEC scale. This is an issue which the Court can helpfully determine at this stage since it is in a good position to do so and will be in a better position than any subsequent court to decide on whether the Claimant’s case initially or by virtue of its actions to date was ever really suitable for determination in IPEC.”

137. Salts opposed this, but it does not appear that Salts asked HHJ Hacon to order that the pre-transfer costs should be subject to the IPEC scale cost limits in any event.

138. HHJ Hacon declined to make the order requested by Pelican. To the contrary, his order recited: “AND UPON the Court indicating at the hearing of the application to transfer that costs prior to transfer should be assessed in accordance with the usual IPEC scale cost caps pursuant to CPR r.46.21 and Practice Direction 46 albeit costs were reserved and this was an issue for the judge making the assessment”.

139. Paragraph 2 of the order provided: “Costs reserved”. The judge’s costs order

140. Despite what was said in the recital to HHJ Hacon’s order, the judge declined to order that Pelican’s costs prior to transfer be assessed in accordance with the IPEC scale cost caps. He expressed his reasons for this in his costs judgment of 1 April 2025 [2025] EWHC 1056 (Pat) as follows: “21. Mr Davis submits that CPR 46.20 applies only to proceedings that start and finish in the IPEC. It appears to me from the order of HHJ Hacon that the judge was of the same view. His indication in a recital his order of reservation of costs was to give to the trial judge discretion in that matter. A reason for proceeding that way on transfer in IPEC is that it would not be clear at the time of transfer how the matters would develop in the Patents Court or whether work carried out before the transfer might in the Patents Court become useful and part of the case once transferred. It therefore appears to me that it is not an invariable rule that costs incurred in IPEC before transfer to the Patents Court can only be assessed at the IPEC scale.

22. As a result of that, I will not make a costs order on the IPEC scales for those parts of the case taking place there. The work that I understand took place in the IPEC phase formed an integral part of a significant dispute in the Patents Court. In this case the defendant has successfully defended the claim and should be able to recover its costs of doing that in the court in which the matter was determined.” Standard of review

141. The correct approach of an appellate court to appeals on costs is that described by Stuart-Smith LJ in Roache v News Group Newspapers Ltd. [1998] EMLR 161 at 172 and cited with approval by Lord Woolf MR in AEI Rediffusion Ltd v Phonographic Performance Ltd [1999] 1 WLR 1507 at 1523: “Before the court can interfere it must be shown that the judge has either erred in principle in his approach or has left out of account or has taken into account some feature that he should, or should not, have considered, or that his decision was wholly wrong because the Court is forced to the conclusion that he has not balanced the various factors fairly in the scale.” Analysis

142. Salts contends that the judge was required to assess the costs incurred by Pelican in accordance with the IPEC scale costs caps. In the alternative, Salts contends that, if the judge had a discretion to exercise, his exercise of that discretion was flawed.

143. Before considering the issues raised by these contentions, it is first necessary to explain that the provisions in the rules set out above concerning unreasonable behaviour are not relevant. A finding of unreasonable behaviour is the gateway to the making of an immediate costs order in respect of an application pursuant to rule 63.26(2), rather than leaving the costs to be assessed at the conclusion of the trial, which is the default procedure under rule 63.26(1). Where an immediate costs order is made in respect of an application pursuant to rule 63.26(2), those costs are additional to the total costs which may be awarded under rule 46.21: rule 46.22.

144. On the face of the rules, the only bases for making an order for costs which exceed the IPEC scale cost limits are where a party has abused the process of the court or there is a certificate of contested validity: rule 46.20(2). Pelican has never suggested that Salts has abused the process of the court. The Patent did not benefit from a certificate of contested validity, and such a certificate would not have been relevant to Pelican’s costs of successfully defending Salts’ infringement claim anyway.

145. As the judge explained, Pelican’s case is that the scale cost limits only apply to proceedings which start and finish in IPEC. Salts’ primary case is that the scale cost limits apply for so long as the claim proceeds in IPEC, and can only be departed from pursuant to rule 46.20(2), and that this is unaffected by a subsequent transfer of the claim to the Patents Court.

146. The starting point for the resolution of this issue is the provision in rule 46.20(1) that “this Section applies to proceedings in the Intellectual Property Enterprise Court”. The judge expressed the view that HHJ Hacon’s order was premised upon Pelican’s interpretation of this provision. I disagree with this, because the recital to HHJ Hacon’s order is inconsistent with that interpretation. In any event, it seems to me that rule 46.20(1) does not provide a clear answer to the question as to what happens to pre-transfer costs after transfer. Accordingly, it is necessary to consider the legislative scheme more broadly.

147. Counsel for Pelican relied by analogy upon rule 27.15(1), which provides: “Where a claim is allocated to the small claims track and subsequently re-allocated to another track, the costs which may be allowed are those applicable to the track to which the claim is reallocated, as if the claim been allocated to that track at the outset.” In my view this is, if anything, a point against Pelican’s interpretation, because there is no counterpart to rule 27.15(1) in the rules applicable to IPEC.

148. Counsel for Salts submitted that rule 46.20(1) should be interpreted having regard to the purpose of the IPEC costs regime as articulated by HHJ Birss QC (as he then was) in Westwood v Knight [2011] EWPCC 11, [2011] FSR 37 (a case decided shortly after the new costs regime had been introduced into what was then the Patents County Court before it was reconstituted as IPEC) at [20]: “… The purpose of the limits is to aim for certainty for litigants (see section 5 Costs Recovery in the Final Report of the IPCUC’s Working Group on Proposals for Reform of the Patents County Court). The correct approach must be to apply the limits if they can possibly be applied, recognising however that in the end the court always has a discretion as to costs (CPR r44.3) and that includes as to the amount of costs. It is a discretion which in my judgment will very rarely (if ever) be exercised to exceed the limits set by Section VII. For one thing specific exceptions are provided for (r45.41(2)). Furthermore to exercise a discretion on a wider basis in all but the most rare and exceptional case would undermine the very object of the scale in the first place. For the scale to give a measure of certainty to litigants, it has to possible to be sure that the limits will apply well before any costs are incurred and most likely before any action has even commenced. Before they embark on litigation to enforce their intellectual property rights (or defend themselves) the potential users of the Patents County Court system need to be able to make a prediction in advance as to their likely costs exposure. Their legal advisers need to be able to say with confidence that the costs capping provisions can be relied on.”

149. I would entirely endorse this statement of the purpose of the scale costs regime in IPEC, which is one of the key reforms to procedure in the Patents County Court, now IPEC, implemented following the Working Group’s report in order to improve access to justice for individuals and SMEs in intellectual property disputes. (Indeed, I would wish to reserve for future consideration the question whether there is a residual discretion to depart from scale costs in exceptional cases: as HHJ Birss QC observed in Henderson v All Around the World Recordings Ltd [2013] EWPCC 19, [2013] FSR 42 at [12], “the point of the PCC costs rules [is] to favour certainty as opposed to a fully compensatory approach to costs”.) I do not consider, however, that the rationale for scale costs applies, at least with full force, to claims which are started in IPEC, but are then transferred to the Patents Court. It is inherent in such a transfer that, at least so far as future costs are concerned, the parties will no longer be protected by the scale costs provisions against costs orders in larger sums.

150. In my judgment the key to the present issue is provided by paragraph 9.2(1) of Practice Direction 30. This enables IPEC, when transferring a case to the Patents Court, to “specify terms for” the transfer. The only authority on this provision to which we were referred is Comic Enterprises Ltd v Twentieth Century Fox Film Corp [2012] EWPCC 13, [2012] FSR 30 , where HHJ Birss QC stated at [57]: “I will also include a further term in the order for transfer pursuant to PD30 paragraph 9.2(1) namely that the costs incurred in these proceedings prior to transfer will be assessed in accordance with the Patents County Court scale in any event. Such an order is not appropriate in every case but it is appropriate here. That is because in the circumstances of this action the defendant could and should have applied to transfer the case immediately after being served with the Particulars of Claim. Accordingly it is fair that the costs incurred up to now, when the action was in the PCC, are assessed on the PCC scale.”

151. I agree that paragraph 9.2(1) empowers IPEC to make an order when transferring a claim to the Patents Court that costs incurred in the proceedings prior to transfer shall be assessed in accordance with the IPEC scale in any event. I also agree that it lies in the discretion of the judge making an order for transfer whether to make such an order or not. In my judgment it follows that, if no such order is made, the Patents Court has a discretion as to whether or not to assess pre-transfer costs in accordance with the IPEC scale.

152. Given that HHJ Hacon did not make such an order in the present case, but rather reserved the costs, I would therefore reject Salts’ contention that the judge had no power to order Salts to pay above-scale costs in respect of the period prior to the order for transfer.

153. On the other hand, I agree with Salts that the manner in which the judge exercised his discretion was flawed. HHJ Hacon’s order recited that “costs prior to transfer should be assessed in accordance with the usual IPEC scale cost caps”, albeit that he left it open to the Patents Court to make a different order. In my judgment it follows that the exercise of the discretion should have been approached on the basis that HHJ Hacon’s indication could be departed from if, but only if, there was a good reason to do so. The judge did not give any reason for departing from HHJ Hacon’s indication. Rather, he treated the pre-transfer costs as being at large, and hence subject to the approach to costs ordinarily applicable in the Patents Court.

154. It therefore falls to this Court to re-exercise the discretion. Pelican contends that this Court should exercise it in the same manner as the judge. The factors relied upon by Pelican in support of that contention all concern Salts’ conduct of the proceedings in the period prior to transfer. As Pelican’s own submission to him recognised, HHJ Hacon was well placed to assess that conduct, because he took it into account when making the order for transfer, but he did not consider that it justified Salts being exposed to above-scale costs. I am not persuaded that this Court should take a different view. I would therefore vary the judge’s costs order so as to limit the pre-transfer costs payable by Salts in accordance with the IPEC scale.

155. For the avoidance of doubt, I should make it clear that, although I have referred in the preceding discussion to transfers from IPEC to the Patents Court, because that is the factual scenario in the present case, the same analysis applies to transfers of copyright and trade mark claims from IPEC to the High Court. Conclusion

156. For the reasons given above, I would dismiss Salts’ appeal on the infringement issues, but allow it on novelty and on pre-transfer costs. Lord Justice Miles:

157. I agree. Lord Justice Newey:

158. I also agree.