In UK court proceedings, at the appeal stage the parties have traditionally been limited to the cases made at first instance. It is the decision of the lower court that is reviewed by the appeal court, rather than the original question in its entirety; ‘is the patent valid’, for example, or ‘is the patent infringed’. Thus, a patentee, whose patent is declared invalid or only valid to an extent insufficient to establish infringement in a lower court, has normally to go to appeal with the claims considered at first instance. This approach to appeals is well established in the UK and has been confirmed by higher courts (for example in Nikken v Pioneer  FSR 4). This approach contrasts with that taken in some other jurisdictions, for example by the EPO Boards of Appeal, where the appeal stage is to a large extent a second bite of the cherry, and in which claims can be further amended.
There have been exceptions to the UK’s ‘same case’ rule, but these have been few and far between, often involving evidence that could not have been brought, for a practical reason, at first instance. In cases in which the validity of an UK patent arising from a European patent (an EP(UK) patent) is at issue, copending EPO opposition proceedings against the EP patent have the potential to cause a problem, as validity is being considered at the same time by different tribunals that might reach different decisions. Cases where this has actually caused a problem seem to be few, perhaps because of the possibility of a stay of the UK proceedings pending the EPO’s decision. UK appellate courts have always considered the claims after the EPO proceedings have terminated, if available, even if these differ from those considered by the lower courts. Subject to these exceptions, however, in UK court proceedings an unsuccessful patentee has been stuck with the claims as at first instance
The European Patent Convention (2000) allowed for the first time the possibility of voluntarily central limitation of the claims of (or revocation of) an EP patent by the patentee (Art. 105a and Art. 105b EPC). This procedure is available to a patentee at any time (other than when EPO opposition proceedings are pending). The amendments are examined by the EPO only for formal compliance and to ensure that the amended claims are narrower than the previous claims and that the amendments do not add subject matter and do not lack support. There is no requirement for the patentee to explain the need for amendment and no examination of the amended claims for patentability over prior art. Thus, the proprietor of an EP(UK) patent in UK court proceedings who has lost, or who fears losing, at first instance can apply to the EPO to limit the claims of the corresponding EP patent. This application is likely to be successful, in which case the patentee will be able to appeal the UK court decision with claims different from those considered at first instance. The limitation application can be made after the appeal proceedings have begun.
Taking advantage of the central limitation procedure could be used not only to improve a patentee’s chances of having a patent upheld on appeal, but if the case involves an allegation of infringement, the claim can be amended after the patentee has heard the alleged infringer’s case for non infringement, and so perhaps avoid potentially harmful amendments.
This procedure has been used in few cases. In Samsung v Apple  EWCA Civ 250, Samsung appealed a finding of invalidity. During the appeal, they sought central limitation of the EP(UK) patent and requested adjournment of the appeal proceedings pending a decision in the limitation proceedings. Apple’s submissions that this is an abuse of process failed.
Elsewhere in Europe, the Dutch Supreme Court have remitted back to a lower court a case in which a patent was centrally limited during the appeal proceedings. It may be that this approach will find favour in UK. If a case goes to appeal with claims different from those on which the first instance decision was made, the opposing party will not have the opportunity to attack those claims at first instance, so remission to first instance may be justified.
It remains to be seen whether central limitation proves a popular way to revive a patent that has been declared invalid; there is no obvious reason why it should not. It will not be useful in all cases of course; there must be an amendment available that has a good chance of rendering the claims valid while retaining a worthwhile scope. It is hard to see that it will ever be of help in cases in which infringement has been denied by a lower court, as the central limitation procedure can be used, as the name implies, only to limit a patent.
I am indebted to Richard Davis, barrister, of Hogarth Chambers for letting me have the notes for a talk that he gave recently on this topic.
This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.