The test for added subject matter

Intermediate generalisation

7.91 The claims form part of the disclosure but as noted in European Central Bank not everything which falls within the scope of the claims is necessarily disclosed.

7.92 For example, amendments may limit the scope of a claim by the introduction of one or more features from the description or claims, but add matter through what is known as “intermediate generalisation”. This was described by Pumfrey J in Palmaz’s European Patents (UK) [1999] RPC 47 in the following way:

“If the specification discloses distinct sub-classes of the overall inventive concept, then it should be possible to amend down to one or other of those subclasses, whether or not they are presented as inventively distinct in the specification before amendment. The difficulty comes when it is sought to take features which are only disclosed in a particular context and which are not disclosed as having any inventive significance and introduce them into the claim deprived of that context. This is a process sometimes called ‘intermediate generalisation’.”

7.93 The applicability of intermediate generalisations in Singapore has been specifically addressed by the Singapore Courts. Most recently, Lee Seiu Kin J in Novartis AG and another v Ranbaxy (Malaysia) Sdn Bhd [2012] SGHC 253 noted that the concept is firmly entrenched as part of the UK law, but noted that “the policy oriented rules applicable in England by virtue of the European Patent Convention should not be unthinkingly adopted in Singapore without an examination of its compatibility with the local statutory regime”. At [39] he went on to state:

“I am of the view that the principle of intermediate generalization appears to be subsumed under the test of added matter. This is because the question which the test of intermediate generalization seeks to answer is simply whether a person skilled in the art would learn something new which has not hitherto been disclosed in the patent specifications … the ‘right question is whether the proposed amendment would result in the specification disclosing additional matter’ … This is precisely the test which the court has to apply under s 84(3) of the Act.”

7.95 For example, in Teva UK Ltd v Merck & Co. Inc. [2010] FSR 17, the Court found that an amendment of a claim to limit a formulation to a particular pH range was not allowable on the basis that:

“given the paucity of the disclosure about pH generally, the only disclosure that the skilled person would take out of the application as filed for combinations of dorzolamide and timolol would be gellan gum at pH 5.5 to 6.0 and HEC at pH 6. To claim a range of pH 5.5 to 6.0 for dorzolamide irrespective of viscosifier amounts to an impermissible intermediate generalisation.”

7.96 An intermediate generalisation may also occur by the deletion of matter to place emphasis on certain features. For example, in the decision of the Court of Appeals in Merck & Co Inc’s Patents [2004] FSR 16, the applicant sought to limit the claim to a single pill comprising 70 mg of alendronate by deleting other tablet dosages and combinations. This amendment was considered to place particular emphasis on this specific dosage form, when no such importance was indicated in the application as filed, and as a consequence the amendment was not allowable.

7.97 In contrast, in Novartis, an amendment to a claim to limit the scope specific formulations comprising valsartan in free form as the only active agent, and where the composition comprised 2-10% of crospovidone (a disintegrant used widely in pharmaceuticals) was found to be allowable. The Court found that both these features had been clearly and unambiguously disclosed in the application as filed, including in examples of preferred embodiments and specific examples. Moreover, on the question of whether the limitation of the claims constituted an impermissible intermediate generalisation, since the claim did not include other components which were described in “typical” compositions of the invention, the Court considered that nothing turned on this point. The omitted components were considered to have no inventive significance to the person skilled in the art since they were merely coloring and film coating agents that had no effect on the performance of the invention.