The test for added subject matter

Express and implicit disclosures

7.77 The Examiner must consider what has been disclosed both explicitly and implicitly. The addition of matter to that the person skilled in the art would take for granted or consider implicit would generally be allowable (DSM NV’s Patent [2001] RPC 25 at [195]-[202]). For example, an amendment is made to explicitly include a feature that the skilled person would consider an intrinsic part of the invention would probably be allowable.

7.78 A simple example of this type would be an amendment to include the term “wheels” in a specification relating to a bicycle incorporating a new steering assembly would be allowable.

7.79 In Keith’s Application BL O/455/99, the Comptroller stated that matter is only implicitly disclosed if the person skilled in the art would inevitably consider that such matter was included in the application:

“In his judgment, Aldous, J stated in terms that the test for added subject-matter is a strict one and that in order to be acceptable the matter in question must be ‘clearly and unambiguously disclosed [in the application as filed] either explicitly or implicitly’. I believe that is clear as it stands, but in  theface of Mr Keith’s argument to the contrary, I confirm that I interpret the expression ‘disclosed … implicitly’ as meaning that the skilled addressee would recognise that the matter in question, though not actually mentioned, must inevitably be present.”

7.80 It is not sufficient that the added matter was one of several possibilities that could be derived from the original disclosure. This approach is consistent with the approach in a novelty consideration, where a feature may only be considered inherent if the working of the invention would inevitably provide that result.

7.81 It must be noted that this is not an obviousness consideration. Amendments incorporating matter which would have been obvious to the person skilled in the art from the application are not allowable. For example, in Flexible Direction Indicators Ltd’s Application [1994] RPC 207 the invention related to a traffic bollard characterised by its flexibility. The specification originally disclosed that the bollard was made from a compound of two polymers. The applicants sought an amendment to include the use of a single polymer, arguing that it would be obvious to the skilled person that it could provide the desired flexibility. Aldous J noted in this case that the consideration of whether the matter extends beyond the original disclosure “is concerned with what is disclosed, not with that which the skilled reader might think could be substituted or what had been omitted”.