Indirect infringement and consumables – the UPC perspective

Key aspects of indirect infringement by marketing consumable parts of a patented product have been considered recently at the Unified Patent Court.

In finding indirect infringement in ORD_69429/2024 (Brita v Aquashield, UPC_CFI_248/2024, 22 August 2025, ‘Brita’), the Munich Local Division has given guidance on how the indirect infringement test applies to consumables at the UPC; in particular what constitutes “means relating to an essential element of the invention” and the extent to which an exhaustion argument may succeed in cases involving consumables.

The patent in suit and the challenged embodiment 

The patent in suit in Brita relates to various aspects of a water filter jug. In particular, the object of the patent was to provide a valve system designed to prevent water from flowing into the collecting container for filtered water without a filter cartridge being installed in the water filter jug. To achieve this, the filter cartridge is provided with a “valve actuating device” that is configured, once installed in the water filter jug, to open the valve by exerting a horizontal force on it.

The granted claims were directed at a water filter jug, including the valve system and the valve actuating device, a liquid container for the water filter jug including the valve system, and a valve actuating device for the valve system.

The challenged embodiment was a filter cartridge that was compatible for use with the claimant’s water filter jugs and included features that fell within the scope of the claim for the valve actuating device.

The counterclaim for revocation was partially successful, leaving the patent valid only in amended form. In particular, the amended patent claims were directed only to the water filter jug and its use for filtering water.

As the challenged embodiments were filter cartridges (including valve actuating features) and the only remaining product claims were directed towards the water filter jug, the direct infringement claim fell through. Consequently, the only substantive question that remained as far as the infringement proceedings were concerned was whether the challenged filter cartridges, which were marketed in Austria, France, Germany, and Italy, indirectly infringed the remaining claims to the water filter jug including a filter cartridge comprising valve actuating features.

Indirect infringement at the UPC

The law on indirect infringement at the UPC, contained in Article 26 of the UPC Agreement, derives from Article 26 of the Community Patent Convention 1989.^[1]

In particular, paragraph 1 of Article 26 of the UPC Agreement provides that “[a] patent shall confer on its proprietor the right to prevent any third party not having the proprietor’s consent from supplying or offering to supply, within the territory of the Contracting Member States in which that patent has effect, any person other than a party entitled to exploit the patented invention, with means, relating to an essential element of that invention, for putting it into effect therein, when the third party knows, or should have known, that those means are suitable and intended for putting that invention into effect.”^[2]

The elements of the provision that were particularly relevant in Brita were whether the contested filter cartridge was a “means relating to an essential element of that invention” (or simply “essential means”) and whether the “proprietor [has] the right to prevent” the acts or whether that right had been exhausted.

Consumables as essential means

The decision in Brita defines essential means as “means … capable of interacting functionally with one or more features of the patent claim in realising the protected inventive concept” ([227]) and goes on to clarify that what “constitutes an essential element … must be determined on the basis of the subject matter of the invention. Since the patent claim is decisive for determining which subject matter is protected by the patent, all features specified in the patent claim are generally essential elements of the invention” ([227], emphasis added). In particular, the decision explicitly rules out any requirement that the essential element relate to the “core” of the invention or be a distinguishing feature. The means is nevertheless not essential if it “play[s] a completely subordinate role in the context of the protected invention” ([228]).

Applying these principles to the facts of the case, the Munich Local Division found that the cartridge filters are essential means, because they alone are responsible for treating the water, which is the purpose of the water filter jug, and they comprise the valve actuating features in accordance with the claim.

Exhaustion

Another interesting aspect of the decision is in relation to exhaustion. The defendants argued replacement of filter cartridges is merely part of necessary maintenance of the product that ought to be permissible to a user having purchased the filter jug. Therefore, it was argued, the claimant’s patent rights in relation to these parts were exhausted upon sale of the claimant’s water filter jug to the relevant purchaser.

Article 29 of the UPC Agreement provides that “[t]he rights conferred by a European patent shall not extend to acts concerning a product covered by that patent after that product has been placed on the market in the European Union by, or with the consent of, the patent proprietor, unless there are legitimate grounds for the patent proprietor to oppose further commercialisation of the product.”

The Munich Local Division stated that “[s]ince the concept of exhaustion is expressly regulated in Article 29 of the UPC Agreement, there is no need to refer to the national law of the contracting Member States. Rather, the conditions for exhaustion must be developed independently and autonomously by the UPC itself” ([233]).

The decision goes on to state that the “decisive factor […in relation to the maintenance or repair of the patented product by replacing one of its parts] is whether the replacement or substitution preserves the identity of the [patented] product … already placed on the market or whether it creates a new product that is in accordance with the invention” [235]. In assessing whether the replacement constitutes maintenance or repair, or whether it constitutes making the patent product, “[o]ne factor to consider … is whether the replacement or substitution

of the part in question is normally to be expected during the product’s lifetime and whether the public or the purchasers can therefore legitimately expect to be able to continue using the product purchased with the replacement part or to use it multiple times…. However, the situation is different in exceptional cases where the technical effects of the invention are reflected precisely in the replaced part. In such cases, the replacement of the part results in the technical and economic advantages of the invention being realised again and the identity of the patent-protected product originally placed on the market is lost” [236].

The principles adopted by the Munich Local Division reflect the German approach to exhaustion, which is strictly object-oriented (“streng objektbezogen”) in that exhaustion only applies to the specific object that has been placed on the market with the consent of the patent proprietor. Thus, the right to re-manufacture the patented product always remains with the patent proprietor.^[3]

Having established the principles to be applied for the assessment of exhaustion when a patented product has been put on the market, the court did not in the end apply them to this issue at hand. On the facts of the particular case, the Court took the view that the claimant’s product on the market did not fall within the scope of the surviving claims – and thus no exhaustion could have occurred.

Remedies

Given the finding that the contested filter cartridges indirectly infringed the amended patent, the Munich Local Division ordered that the contested filter cartridges may only be offered or supplied with a warning notice to both commercial customers and private end users. The ordering of a contractual penalty in relation to commercial customers was deemed not to be necessary. The warning notice to the commercial customers was that the contested product may not be used in a water filter jug in accordance with the claims of the amended patent. However, as it was deemed that private end users do not have specialist knowledge of patent law, the warning notice to cover such users required an express and clear statement that the contested filter cartridges are not intended for use with the claimant’s specific branded water filter jugs.

Discussion

The approach adopted in this decision places the concept of “making” the patented product at the heart of the assessment of exhaustion. This is a somewhat distinct approach to that usually adopted in the courts in the UK, which generally starts from the alternative concept of an implied licence.^[4] Often the primary concern with respect to an implied licence is whether the patented product can continue to be used for its intended purpose – with the expectation being the consumer has a right to do so.

The UK approach can be seen in the decision of the High Court in Nestec SA & Others v Dualit Ltd & Others [2013] EWHC 923 (‘Nestec’). Here, the concept of “making” the product does have a role (particularly in the assessment of whether the sold consumable constitutes “means suitable for putting the invention into effect”^[5]), but not necessarily one which would in all cases override an implied licence. That is, while a narrow window arguably remains open in the UK courts for rights to be exhausted even if it was found that a consumable (re-)made the patented product, under the Brita approach at the UPC this would appear not to be the case. Combining this with the Court’s remarks concerning “the technical and economic advantages of the invention being realised again” and the relatively open assessment of what constitutes an “essential element”, the UPC appears an attractive forum to pursue indirect infringement claims of this type.

^[1] While the Community Patent Convention did not enter into force, its provisions, including those relating to patent infringement, have influenced directly the law in most European countries, including France, Germany, and the United Kingdom.

^[2] Paragraphs 2 and 3 of Article 26 of the UPC Agreement relate to “means that are commercial staple products” and where the person has a defence to infringement, respectively, and were not at issue in this case.

^[3] Ingo Rinken, ‘Wirkung des Patents: Benutzungsrecht und Verbot der unmittelbaren Benutzung’ in Rainer Schulte (ed), Patentgesetz mit EPÜ (11th edn, Kluwer, 2024) [21], [57]-[58]

^[4] See United Wire v Screen Repair Services (Scotland) [2001] R.P.C. 24 [68]–[69] (Lord Hoffmann) for a comparison of the two concepts. A simple way of seeing the difference between the two concepts in this context is that exhaustion relates to the element of whether the “proprietor [has] the right to prevent” the supply or offer to supply, while implied licence relates to the element of whether the purchaser is “other than a party entitled to exploit the patented invention”.

^[5] Nestec [183]-[205], applying the principles set in Schutz v Werit [2013] UKSC 16.