Abbott Diabetes Care Inc & Ors v Dexcom Inc & Ors

In assessing obviousness, the court must consider the notional skilled team, its common general knowledge and the teaching of each item of prior art without hindsight. A team member’s individual expertise cannot replace consideration of the team’s collective capabilities, although members may take the lead in their own disciplines. Schematic patent drawings should be read as schematic disclosures, not as detailed engineering drawings. Routine design choices required to implement the prior art do not ordinarily constitute inventive steps. The party alleging obviousness must establish that the complete route from the prior art to the claimed combination would have been obvious, rather than showing that each isolated problem could be solved. On construction, differing language such as “coupled” and “operatively coupled” may have distinct functions in the claim.

The claimants alleged that the Dexcom G7 infringed EP 3 730 044 B1, a patent concerning an integrated continuous glucose monitoring assembly containing a sensor, sensor electronics and an insertion device. Dexcom denied infringement and challenged validity for obviousness over Heller, Ethelfeld and Fennell, insufficiency and added matter concerning claim 5.

The central issues were the skilled team and its common general knowledge, construction of the insertion and retraction integers, infringement, obviousness and the added-matter attack.

1. Construction. The expression “activation switch” was given a broad construction. However, “coupled to the housing” in integer 1.9 and “operatively coupled to the housing” in integer 1.10 were not interchangeable. The former required the housing’s movement to cause manual insertion of the needle; the latter described the relationship enabling the bias mechanism to cause automatic retraction. Claim 1 was therefore limited to manual insertion. “Automatically” in the retraction integer concerned the automatic nature of the retraction process, not necessarily automatic initiation.
2. Infringement. The G7 used automatic insertion. Its needle was not coupled to the housing in the sense required by integer 1.9. It therefore did not infringe.
3. Skilled team and obviousness. The patent was addressed principally to design and electronics engineers working within a wider CGM team. The team possessed the practical knowledge which the patent itself assumed, including sensor manufacture, sterilisation and spring-loaded insertion and retraction mechanisms. The court applied the structured approach in Pozzoli and assessed each prior-art reference in context. Commercial considerations and alleged industry prejudices received little weight.
4. Heller. Heller disclosed an integrated sensor and electronics arrangement, together with insertion, retraction, activation, housing, adhesion and packaging options. Adapting its schematic embodiments involved routine implementation choices. Claims 1, 2, 3, 4, 5 and 7 were obvious over Heller.
5. Ethelfeld and Fennell. The alleged combination based on Ethelfeld did not establish that the complete design falling within the claims would have been obvious. Fennell, read as a whole, disclosed the conventional arrangement in which the sensor was inserted and later connected to the transmitter, not the claimed integrated assembly. The claims were therefore not invalid over either reference.
6. Added matter and insufficiency. The added-matter attack on claim 5 failed because the application disclosed engagement and disengagement of the introducer needle and sensor electronics assembly. The insufficiency issues did not require further determination.
7. Disposition. The G7 did not infringe. EP044 was invalid for obviousness over Heller, but not over Ethelfeld or Fennell. The added-matter attack failed.