In short, Philips sued Nintendo, alleging that the latter's Wii computer game console infringed three of its patents for computer implemented inventions. Nintendo counterclaimed for revocation and Philips then applied for conditional amendments to all three patents. The court had to decide on infringement and, inter alia, (i) whether the proposed amendments should be allowed or whether they would introduce added matter; (ii) whether one of the patents was obvious over the prior art, and (iii) whether the two other patents were valid as granted and whether there was an element of double patenting.
Birss J held that all three patents were invalid as granted but that the second and third, when amended, were both valid and infringed. He gave some helpful guidance with regard to double patenting that runs like this (at paragraphs 302 to 310):
- First, the idea at the heart of the double patenting objections is that ordinarily an applicant should not obtain two patents for the same thing filed at the same time. That is because an applicant ordinarily has no legitimate interest in doing this [if this is so, should it not then apply equally to other registered IP rights, for example trade marks, where the question of double protection is more complex on account of considerations such as genuine use?].
- Second, however "double patenting" is not a ground of revocation of a patent. It is not in s72 of the Act [Patents Act 1977, here] nor Art 138 EPC [European Patent Convention, here]. In the UK there are particular circumstances in which double patenting can lead to refusal (or revocation on the Comptroller's initiative). They are defined by statute (s18(5) and s73(2)).
- Third, the EPO does recognise a double patenting objection as a ground for refusing amendments to a divisional application. Two conditions have to be satisfied. The proposed amended divisional claim has to claim the same subject-matter as a parent and the applicant has to have no legitimate interesting in obtaining the divisional claim. Generally if the first condition is true the second is likely to follow but there can be cases, such as T 1423/07 in which a legitimate interest in obtaining the divisional claim can be shown to exist irrespective of the relationship between the scope and subject matter of the parent and divisional claims.
- Fourth, the EPO does recognise that if the independent claim of a divisional has the same scope as an independent claim in the parent then double patenting exists and an amendment which would give rise to that state of affairs will be refused. It is a test of substance and not merely form. It is not the settled jurisprudence of the EPO that double patenting exists merely because the scopes of the two claims overlap.
- Fifth, one needs to take care when comparing the different procedural circumstances in which this point can arise. The EPO only deals with one patent at a time and so an EPO case considering a divisional application will not contemplate making changes to the claims of the parent to overcome an objection. Although post-grant centralised amendments are now possible in the EPO, that is a fairly recent development. In the UK the point only arises in two very specific statutorily defined circumstances.
- Sixth, the judgment of the Court of Appeal in Marley's Roof Tile  RPC 231 is directed to a point on statutory construction of s73(2) of the 1977 Act. Although both s73(2) and the objection applied by the EPO are referred to as "double patenting" and have the same underlying rationale, the Court of Appeal's judgment is not binding on the question arising in relation to the exercise of discretion under s75 of the Act.
- Seventh, a patentee may have a legitimate interest in obtaining a divisional patent with claims which are broader than but encompass the scope of a parent patent. During prosecution of the parent the examiner may object to a broad claim but indicate that a narrower claim would be accepted. The patentee may not agree but may recognise that to win the point will need many more months or even years of proceedings and possibly appeals. This is true in both the EPO and UKIPO. However in the meantime the patentee may want to obtain an early grant because a competitor has launched an infringing competitive product [This is where commercial considerations come into play ...]. The infringing product may be very close to the patentee's invention and within the narrow claim on offer. At an early stage in this new market for a new product the patentee's business may be particularly vulnerable and the loss caused by the infringement may well not be fully compensatable in damages under s69 of the 1977 Act (Art 67 EPC). Thus the patentee decides to take what is on offer and obtain grant of the parent patent with a narrow claim. Under s76 of the Act and Art 123(3) EPC post grant amendments are not permitted to widen the scope of monopoly so, in order not to give up scope to which the patentee is entitled, a divisional application is filed. If the divisional is granted with a broader scope than the parent then the patentee's stance has been entirely vindicated.
- In my judgment a patentee in the case I have described has a legitimate interest in obtaining the divisional in addition to the parent and it would be wrong to apply a double patenting objection based on overlapping scope such as in T307/07 or Marley's Roof Tile to prevent this. I also do not believe that a disclaimer or carve out amendment from the divisional to remove the scope of the parent claim should be required since such negative features can introduce uncertainty and make the claims hard to interpret.
(i) The two patents must have the same priority dates and be held by the same applicant (or its successor in title);
- I find that as a matter of UK law a double patenting objection taken as a ground for refusing a post-grant amendment to a claim can be taken but should only be taken in the following circumstances:
(ii) The two claims must be for the same invention, that is to say they must be for the same subject matter and by this I mean they must have the same scope. The scope is considered as a matter of substance. Trivial differences in wording will not avoid the objection but if one claim covers embodiments which the other claim does not, then the objection does not arise.
(iii) The two claims must be independent claims. This necessarily follows from the rejection of the point on overlapping scope. If two independent claims have different scope then there is no reason to object even if the patents contain dependent claims with the same scope. The point might arise later if an amendment is needed e.g. to deal with a validity attack but in the case the point can be taken then.
(iv) If the objection arises in the Patents Court in which both patents are before the court then it can be cured by an amendment or amendments to either patent.
(v) Even if the objection properly arises in the sense that two relevant claims have the same scope, if the patentee has a legitimate interest in maintaining both claims then the amendment should not be refused.Do readers agree with this summary, or does it invite comment and qualification?