Convatec Ltd and Others v Smith & Nephew Healthcare Ltd and Others

JurisdictionEngland & Wales
CourtChancery Division (Patents Court)
JudgeHis Honour Judge Birss QC
Judgment Date27 July 2011
Neutral Citation[2011] EWHC 2039 (Pat)
Date27 July 2011
Docket NumberCase No: HC 10 C 03618

[2011] EWHC 2039 (Pat)




St. Dunstan's House

133–137 Fetter Lane

London, EC4A 1HD


His Honour Judge Birss QC

(Sitting as a Judge of the High Court)

Case No: HC 10 C 03618

(1) Convatec Limited
(2) Convatec Technologies Inc.
(3) Convatec, Inc
(1) Smith & Nephew Healthcare Limited
(2) Smith & Nephew Plc
(3) Speciality Fibres and Materials Limited
(4) Stephen Law


Messrs. Latham & Watkins) appeared for the Claimants.


Messrs. Slaughter and May and Messrs. Bristows) appeared for the

First, Second and Third Defendants.

Hearing dates: 11th, 12th, 13, 15th July 2011

Approved Judgment

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


His Honour Judge Birss QC





The witnesses


Technical background


The person skilled in the art


Common general knowledge


The patent


The claims


Construction – the law


Construction of the claims in this case


Claim 1


Claim 3




Infringement on ConvaTec's construction








'746 Bahia


Common General Knowledge alone








In these proceedings the claimants ("ConvaTec") contend that the defendants have infringed various intellectual property rights held by ConvaTec relating to wound dressings. ConvaTec have a wound dressing product called Aquacel. It is based on a cellulose derivative, carboxymethyl cellulose ("CMC"). The nub of the complaint is that the first and second defendants ("Smith & Nephew") wish to sell a wound dressing called Durafiber. Durafiber is made from a blend of cellulose fibres called Tencel and fibres made from cellulose ethyl sulfonate ("CES"). The CES fibres for Durafiber are made by the third defendant ("SFM"). The fourth defendant is an ex-employee of the claimants now working for the third defendant. ConvaTec contend that Durafiber infringes various of their rights.


As a whole the proceedings include or have included claims for infringement of three ConvaTec patents, a substantial claim for misuse of confidential information, a claim for trade mark infringement and a patent entitlement claim. The corporate defendants gave an undertaking in December 2010 not to sell Durafiber pending an expedited trial of the aspects of the proceedings which concern Durafiber itself. This is that expedited trial. There are other issues between the parties which remain live but which do not fall to be decided on this occasion because they do not concern rights relating to Durafiber itself. The other issues relate essentially to using silver with wound dressings.


Until two weeks ago this trial was to be concerned with three patents (EP (UK) 0 927 013, EP (UK) 1 085 912 and EP (UK) 0 616 650) and that part of the misuse of confidence claim which bore on Durafiber itself. Shortly before trial ConvaTec dropped this part of the breach of confidence claim as well as the claims in relation to EP (UK) 1 085 912 and EP (UK) 0 616 650. The breach of confidence claim which was not due to be heard at this trial (essentially about silverisation) remains as does the entitlement claim. In relation to EP (UK) 1 085 912 ConvaTec will submit to an order for revocation. In relation to EP (UK) 0 616 650 ConvaTec having dropped the infringement claim, the defendants have dropped their claim for revocation of that patent.


The only live issue for this trial therefore is the claim for infringement of EP (UK) 0 927 013 and the counterclaim for revocation on the ground of invalidity. The defendants rely on three items of prior art: PCT Application publication number WO 96/13282 ("Qin"), US patent 4,256,111 ("Lassen") and PCT Application publication number WO 94/16746 ("Bahia"). They were all published before the priority date of the '013 patent. There was another item of prior art called Qin 2 but that was dropped at the start of the trial. There is also a plea of insufficiency.


The '013 patent is held by the second claimant and the first claimant is an exclusive licensee under the patent. ConvaTec alleges that Durafiber infringes claims 1, 3 and 9 and alleges that claims 1, 3 and 5 are independently valid. Thus the only issues I need to be concerned with are infringement and validity of claims 1 and 3 and validity (but not infringement) of claim 5. Claim 9 is not said to be valid independently of claims 1 and 3.


There is also a point on the liability of the second defendant even if (which the defendants deny) the patent is valid and infringed by the first and third defendants.


Mr Piers Acland QC leading Dr Brian Nicholson instructed by Latham & Watkins appeared for ConvaTec. Dr Justin Turner QC leading Mr Mark Chacksfield appeared for both SFM and Smith & Nephew. For this purpose counsel were instructed by Slaughter and May for SFM and by Bristows for Smith & Nephew. Given that the claim for misuse of confidential information insofar as it was to be addressed at this trial was no longer live, Dr Law did not appear and was not represented.

The Witnesses


ConvaTec's expert witness was Stephen Bishop. He has a BSc from Southampton University in Biochemistry and a Postgraduate Diploma in Industrial Pharmaceutical Sciences from the University of Brighton. He is a member of the British Association for Research Quality Assurance, a member of the Society of Biology, a Chartered Biologist and a member of the Institute of Materials Minerals and Mining (Packaging) Society. Mr Bishop has 26 years experience in the medical device industry. He started work in that area at Amersham International in their Cardiff Quality Control/Assurance Laboratories in 1984, moved to a division of Unilever in 1987 to work on the development of in vitro diagnostic products for monitoring pregnancy, fertility and the human endocrine system and moved to ConvaTec in 1990. He has worked at ConvaTec ever since and continues to do so. Since 1992 Mr Bishop has worked on the development of fibrous wound care products. In 1992–1996 he worked on Aquacel product development. He is one of the named inventors of the '013 patent in this case.


Mr Bishop has played a central role in this litigation from the outset and candidly accepted that he had been seeking to do the best for his employer in that regard. The defendants submitted that Mr Bishop was in an impossible position as an expert witness. They submitted that he was personally responsible for what they called the false allegations which had been at the heart of the confidential information claim namely that the way of making Aquacel was confidential. Mr Bishop oversaw ConvaTec's experiments in this case and he accepted, candidly in my judgment, that if the experiments do not stand up then that will be a matter of personal embarrassment to him. He accepted he was under significant personal pressure.


As regards confidential information Mr Bishop explained that his factual evidence that the Aquacel process was confidential was given when he believed that state of affairs to be true. He had checked the position to his satisfaction. When the defendants showed that in fact the recipe had been published, it was to be found in patent specifications Mr Bishop had not checked because he did not think they were relevant. I accept his evidence on this issue. In my judgment this does not undermine Mr Bishop's standing as a witness.


Nevertheless there is no doubt that Mr Bishop's position as an expert witness in this litigation was not an easy one. He was only appointed to act as an expert relatively late on in the proceedings. Dr Turner asked him about his obligations as an expert. Mr Bishop was candid that until appointed as an expert he had been an advocate for ConvaTec but he said that after he was appointed, he accepted and understood his duties to the court. Mr Bishop was indeed in a difficult position but in my judgment when he was in the witness box he was doing his best to help the court. He gave fair answers to the questions asked and I have no reason at all to reject his evidence simply because of the position he was in save in one respect. The only aspect of his evidence which gave me any concern related to the experiments. The experiments in the Notice had been conducted well before Mr Bishop was an expert. At the time of the Notice he was simply an employee of ConvaTec doing his best for his employer. I have no doubt whatsoever about Mr Bishop's integrity in giving his answers on this topic in cross-examination and trying his best to help the court but in my judgment his ability to be objective about what the experiments showed was compromised from the start. I cannot place much weight on Mr Bishop's evidence about the experiments.


Mr Woodings is an experienced fibres scientist who specialises in cellulose chemistry. He is a consultant to the nonwoven and fibre industries and has over 50 years experience in the industry. Between 1982 and 1994 he worked in the Courtaulds Research Division and from 1994 and 1998 he was Market Development Director for Tencel Fibres Europe. He was commissioning editor and author of the book 'Regenerated Cellulose Fibres', and also contributed to Kirk Othmer's Encyclopaedia of Chemical Technology and the Encyclopaedia of Polymer Science and Technology on the same topic. He was an excellent witness.


Dr Kettlewell is an R&D chemist with a PhD in polymer...

To continue reading

Request your trial
3 cases
  • Convatec Ltd and Others v Smith & Nephew Healthcare Ltd and Others
    • United Kingdom
    • Court of Appeal (Civil Division)
    • 2 May 2012
    ...EWCA Civ 520 [2011] EWHC 2039 (Pat)" class="content__heading content__heading--depth1"> [2012] EWCA Civ 520 [2011] EWHC 2039 (Pat) IN THE COURT OF APPEAL (CIVIL DIVISION) ON APPEAL FROM THE HIGH COURT OF JUSTICE CHANCERY DIVISION (PATENTS COURT) HHJ BIRSS QC (SITTING AS A ......
  • Smith & Nephew Plc v Convatec Technologies Inc. T.J. Smith & Nephew Ltd and Another (Third Parties)
    • United Kingdom
    • Chancery Division (Patents Court)
    • 12 December 2013
    ...the other. The only issue remaining was about the 013 patent. I held that Durafiber did not infringe a valid claim of that patent ( [2011] EWHC 2039 (Pat)). That conclusion was upheld in the Court of Appeal ( [2012] EWCA Civ 520). The result of that first action is that Smith & Nephew a......
  • Convatec Ltd and Others v Smith and Nephew Ltd and Others
    • United Kingdom
    • Chancery Division (Patents Court)
    • 21 December 2011
    ...and some other matters. It deals with the costs of the case which was the subject of my judgment handed down on 27 th July 2011 [2011] EWHC 2039 (Pat). However, as explained in paragraphs 1 to 4 of that judgment, by the time the matter came on for trial, many of the allegations had fallen ......

VLEX uses login cookies to provide you with a better browsing experience. If you click on 'Accept' or continue browsing this site we consider that you accept our cookie policy. ACCEPT