Dr Juliette Boynton

September 2026

Abbott is the proprietor of a patent describing a continuous glucose monitoring device and a method of assembling the same.  SiBio provide devices for continuous ketone monitoring, and Abbott were concerned that they were about to launch a new product that would infringe their patent.  Consequently, Abbott sought a preliminary injunction against SiBio, and SiBio responded by filing a revocation action.  While the preliminary injunction request was refused, the revocation was successful and Abbott appealed.

The main issue in the appeal centred around whether claim 1 contained added matter, with SiBio suggesting that this claim contained an intermediate generalisation.  Specifically, the claims were amended during prosecution to include features from an exemplary embodiment and relating to an enclosure of the device holding the glucose sensor electronics.  However, the embodiment also described the presence of an “elastomeric sealing member” in the recess of the enclosure to seal the electrical contact of the glucose sensor.  Thus, the question was whether the absence of the “elastomeric sealing member” added matter?

The Court confirmed that the test for added matter is “what the skilled person would derive directly and unambiguously using his common general knowledge and seen objectively and relative to the date of filing, from the whole of the application as filed, whereby implicitly disclosed subject-matter, i.e. matter that is a clear and unambiguous consequence of what is explicitly mentioned, shall also be considered as part of its content”.  Thus the Court considered whether not having an elastomeric sealing member in the recess of the enclosure causes the subject matter of the claim to extend beyond the content of the application as filed, and thus to represent new technical information.

The first step of this analysis is to consider the technical effect that the invention aims to achieve and then consider whether the omitted feature contributes to this effect.  Specifically, the Court noted that:-

“It matters when considering whether the skilled person would understand from the disclosure of the application as a whole that there is a structural or functional relationship between the omitted feature and the other features of the claimed embodiment or, in other words, when considering whether there is an inextricable link with such other features or, yet differently worded, whether such omitted feature is essential to the invention.”

In assessing the technical effect and core of the invention, the Court considered that this includes keeping the glucose sensor assembly and the enclosure that subsequently houses the electronics separate until their application to the skin to enable different sterilization methods, and that the device can be moved freely over the skin of the patient to find the right position before being adhered to the skin in a single step.

Thus, the core of the invention is that it:-

“allows the enclosure (which houses the electronics assembly) to be first included in the applicator, and allows the subsequent coupling with the sensor assembly (containing the sensor electronics) – by insertion of the connector support (which is coupled with the sensor electronics) in the recess formed in the bottom exterior surface of the enclosure, thus from beneath, so that the applicator containing the thus assembled on-body device can move freely over the skin surface before it is applied to the skin in one step.”

Based on this, the Court concluded that the skilled person would not consider that elastomeric sealing in the recess of the enclosures of the electronic assembly was necessary for achieving the technical effect of claim 1.  The sealing of the device is not functionally related to the features of claim 1 and the achieving of the technical effect.  The electrical connection between the sensor assembly and the electronic assembly is created when the electrical contacts come together as a result of the connector support being shaped to fit the recess.  While some form of sealing will be necessary to protect the electrical connection, the skilled person would understand this and also understand that there are many options for such sealing.  Indeed, the specification describes other forms of sealing.

The Court concluded that :-

“It follows from the above considerations that the application does not teach the skilled person that there is a structural or functional relationship / an inextricable link between any particular type of sealing, including an elastomeric sealing in the recess of the enclosure, and other features of claim 1, or – differently worded – that the use of any particular type of sealing, in particular an elastomeric sealing in the recess of the enclosure, is essential for achieving the technical effects of the invention as described above (para. 21-25).”

While the UPC applies the law of the EPC, it is not obliged to follow EPC case law and is developing its own, independent, albeit closely related, path.

Here the UPC has dismissed the EPO concept of an “intermediate generalisation” to return to the basic principles of added matter  To determine whether an amendment that includes importing one or more features from a particular embodiment in the application into a claim, while omitting one or more other features of this embodiment extends beyond the content of the application as filed, it is necessary to assess the technical effect that the invention aims to achieve, and whether the omitted feature(s) contributes thereto.  If the omitted feature(s) do not contribute to the technical effect of the claim, it appears that the UPC has found that there is no added matter, even if there is no explicit disclosure of the claimed combination of features apart from the omitted feature(s).