There are many little known and little used corners of Patent Law. This article shines a light on one such area.
At the end of 2007 the European Patent Office (EPO) introduced a new procedure which enables the proprietors of European patents to limit or revoke their patents centrally. On grant, European patents become separate national patents in the countries in which they are validated. This procedure enables the scope of the European patent to be limited, or the patent to be revoked, in all countries in a single action.
Many European countries have procedures for post-grant amendment of patents. In the UK, for example, a granted patent may be amended either on application to the UK Intellectual Property Office or to the Court. Often an application to amend will be made during litigation, for example to restore the validity ofa patent over prior art. As a result of the introduction of the EPO procedure, the patent proprietor now has a choice of forums in which to amend.
Although at first sight attractive, the EPO’s central limitation procedure has not proved particularly popular. Data is hard to come by but there are probably only in the order of one to two hundred limitation applications made a year. By contrast, over three thousand oppositions are decided every year with many more being terminated before reaching a decision.
Patentees will amend post-grant for various reasons, but often to take into account new prior art and/or generally to ‘improve’ the patent where litigation is contemplated; they may wish to improve the intelligibility of the claims or correct errors. However, the central limitation procedure can only be used where the new claims limit the protection. The EPO considers that ‘limitation’ means a reduction in the extent of protection and does not consider clarifications or changes made to protect a different subject to be limitations. The EPO does not allow non-limiting amendments that are not a consequence of the limitation and their guidelines explicitly exclude amendments that generally improve the patent or make cosmetic changes.
Applications for limitation are only examined to check that the amendments are, indeed, a limitation. Also that they meet the EPO’s requirements for clarity, and that they do not either add new subject matter or extend the scope of protection. The patentee does not have to explain why limitation is desired and there is no examination of the novelty or inventive step of the limited claims, for example over newly discovered prior art.
The restriction on adding subject matter or extending the protection also exists in UK post-grant amendment proceedings. However, the UK has a general provision to allow a patentee to amend after grant rather than a specific provision allowing limitation of patents. It would appear, therefore, that the UK post-grant amendment practice is more flexible than EPO limitation. This will be a factor in deciding where is best to amend and may account for the apparent lack of interest in the EPO option.
Of course, procedures in other countries, where they exist, will vary. Patentees need to be aware of the existence of the central limitation system and there will be occasions on which it is appropriate to use it. It has the advantage of limiting the patent in all states covered by the patent as well as being cheap, relatively quick and avoiding a discussion of the merits of the amended claims. Proceedings are generally concluded in less than a year.
There has been some recent interest in central limitation in the context of the ongoing patent wars between Apple and Samsung. While an Appeal was pending in the English Court, Samsung filed a limitation application at the EPO. The amendments put forward were different from those previously offered to the UK High Court. The UK Court of Appeal held that Samsung were perfectly entitled to apply for central limitation at this time as the European Patent Convention allows central amendment at any time provided that no opposition is pending in the EPO. As other observers have noted, Samsung could obtain, via the limitation procedure, claims that have not been considered by the UK Courts at first instance which raises many questions regarding the interplay between national litigation and central limitation.
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.