IP Cases & Articles

Central limitation of patents on existing litigation

From 13 December 2007, it became possible for a patentee to seek a ‘central limitation’ (or even revocation) of a granted European patent. If accepted, the effect of this would have retrospective effect back to the date of initial grant and would extend to all designated patents.

The intention was for this to be (relatively) quick – a few months – and only to involve an examination of issues, namely whether:

a. the new claims were a limitation of the current claims;
b. the new claims were clear and concise; and
c. they did not involve ‘added matter’ either extending the scope of protection or going beyond the subject matter of the application as filed.

If the new claims passed this examination, then the EPO had to accept the new claims.

In practice, this procedure has not been used a great deal so far and average times are nearer twelve months, but it is now becoming part of a patent litigator’s armoury – particularly where there are proceedings in a number of European jurisdictions. It does, however, raise quite complex issues of res judicata/issue estoppel/abuse of process, as well as the relationship between existing local proceedings and this centralised procedure.

Apple v Samsung

This issue was raised in yet another round of the Apple and Samsung litigation, where the English Court of Appeal was asked by Samsung to delay their pending appeal (whose patents had been found invalid at first instance) whilst the European Patent Office (EPO) reviewed an application for central limitation of the two patents in issue.

The application to the EPO had been made after the appeal had been filed in England and the amended claims were different to conditional amendments filed by Samsung in the High Court proceedings, which the first instance judge had been asked to consider (and rejected as not overcoming his findings of invalidity). There were also parallel proceedings in Germany (where one of the patents was also held invalid), Italy and France (neither of which had yet come to trial).

The problem for the English Court of Appeal was that, in English litigation, there is a strong emphasis on parties putting all their arguments before the first instance court (and this should include any proposed claim limitations).

The expectation is that litigation should be final and that parties should not have ‘two bites of the cherry’ by raising new issues either on appeal or in new proceedings.For this reason, appeals theoretically only involve a review of the first instance decision, not a rehearing (as is the case in several other European countries).

If Samsung’s amendments were accepted by the EPO, there was a risk that the appeal would be effectively rendered redundant, as the amended claims would now be different to those at issue and considered at trial (and in respect of which amended claims, no evidence would have been given at trial and no findings of fact or decisions made). This might mean that the case would have to be remitted back to a first instance court.

There have been a number of English cases over recent years, where a European patent (UK) was initially held invalid in England but subsequently the European Patent was held valid (ie, maintained) in opposition proceedings on the basis of new (amended) claims. In such cases, the Court of Appeal did consider the appeal on the basis of the new claims. There was no case dealing with a central limitation, although the Dutch Supreme Court had considered the issue in the Scimed case and had remitted the case back to the Dutch Court of Appeal to review the claims as limited on central limitation.

Thus, on the face of these precedents, Apple was in difficulty in resisting the request for a delay. However, there was a line of cases in the English Courts that had held that applications to amend a patent after a first instance trial should be refused if they would require a second trial as to the validity of the amended claims (see Nikken v Pioneer, see useful links, below). This was on the basis of an exercise of the court’s overarching discretion as to how litigation should be conducted (ie, not having two bites at the cherry).

On these grounds, Apple argued that the first instance judge would never have granted Samsung leave to appeal if the central limitation procedure had been made known to him as, to do so, would be contrary to these cases. Further, they argued that Samsung now had to seek leave to amend its Notice of Appeal (to refer to the claims proposed to be amended at the EPO) and that application should be refused (based on the above case law). The problem for Apple was that the ‘central limitation’ procedure was a right which the European Patent Convention (EPC) has given Samsung and there is seemingly no discretion given to a national court to deny that right.

Whilst the Court of Appeal did not say there could never be a situation where the court would not consider a late-filed application for central limitation as an abuse of process, this was held not to be the case in these proceedings. Given that the central limitation examinations were expected to be complete in a few months, the appeal was adjourned until after a final decision was reached (and Apple was allowed to reserve its position about any costs wasted as a consequence). This case highlights again the somewhat unsatisfactory interaction between the desire for finality and certainty in national court proceedings and the procedures at the EPO.

This relationship was discussed in last year’s Supreme Court discussion in Virgin Atlantic v Zodiac (see useful links, below) where the subsequent amendment during an EPO opposition of a patent fully litigated in the UK resulted in no damages claim being allowed, despite the fact that the English litigation had found the patent valid and infringed and had become res judicata. This was on the basis that the effect of the amendment to the patent’s claims was retrospective and, as these new claims were not infringed, there had never been infringement.

The relationship was further discussed in IPCom v Nokia (see useful links, below) where the court set out guidelines for considering whether to stay English proceedings where there are concurrent EPO opposition proceedings.

Whilst central limitation proceedings may remain relatively rare, they are worth considering in suitable cases. The advent of the unitary patent and the Unified Patent Court may reduce their use (although even that is not clear), but for the time being at least it is a strategy that should not be ignored.

Useful links

  1. Virgin Atlantic Airway v Zodiac Seats UK - Absolute Defence to a Liability for Damages.
  2. Stays of UK Patent Proceedings: Court of Appeal Issues Revised Guidance.
  3. Nikken v Pioneer.