We analyse direct infringement under Article 25 of the UPC Agreement (UPCA), including the broad interpretation of “offering” a product, the treatment of disassembled products, and the circumstances in which managing directors and third parties may be held liable. We also consider indirect infringement under Article 26 UPCA, including the important Brita v Aquashield decision on consumables. Finally, we address the developing doctrine of equivalents, which remains an area of evolving jurisprudence awaiting further clarification from the Court of Appeal.
Direct infringement
Article 25 of the UPCA defines the acts that constitute direct infringement:
(a) making, offering, placing on the market or using a product which is the subject matter of the patent, or importing or storing the product for those purposes;
(b) using a process which is the subject matter of the patent or, where the third party knows, or should have known, that the use of the process is prohibited without the consent of the patent proprietor, offering the process for use within the territory of the Contracting Member States in which that patent has effect;
(c) offering, placing on the market, using, or importing or storing for those purposes a product obtained directly by a process which is the subject matter of the patent.
Below we address some specific case law and principles.
Product claims
For product claims under Article 25(a), the alleged infringing product must show every claimed component; cases where only certain features of a product claim are infringed may instead constitute indirect infringement under Article 26 UPCA (Ona Patents v Google). Also consider the doctrine of equivalents, addressed below.
“Offering” a product
The Court of Appeal interpreted the concept of “offering” under Article 25(a) broadly, understanding it in economic terms rather than a strict legal sense. An offer need not constitute a binding contractual offer capable of acceptance; it is sufficient to present an item in such a way that a consumer can make an offer to purchase, rent, or lease it. For example, advertising products in brochures or on websites accessible in the UPC territory can constitute an offer (Belkin v Philips, Rematec v Europe Forestry, and Honeywell v Sovex).
Supply of disassembled products
The UPC has developed jurisprudence on whether supplying disassembled parts can constitute direct patent infringement under Article 25(a) of the UPCA, rather than merely indirect infringement. The leading case is HAAS v Windhager concerning a patent for a garden bed edging system.
The Court held that where a patented product is designed so that its components can be easily assembled at the place of use, the offering or selling of all components for on-site assembly may constitute direct patent infringement rather than indirect infringement. The Court also held that where a patented product consists of at least two identical and coordinated components intended to be assembled together, selling a single component may constitute direct infringement provided “reference is made to the possibility of assembling or if this is otherwise obvious”.
The Court’s reasoning focuses on circumstances when a patented invention is specifically designed for straightforward on-site assembly. In those cases, treating the supply of all unassembled components as direct rather than indirect infringement is appropriate because it avoids the need for patentees to pursue actions under indirect infringement (Article 26 UPCA), which carries additional requirements: that the alleged infringer knew or should have known that the means supplied were suitable and intended for putting the invention into effect.
Instigator, accomplice, or accessory liability
The Court of Appeal has ruled that an “infringer” within the meaning of Article 63 UPCA, in conjunction with Article 25 UPCA, is also someone who does not themselves carry out the infringing acts, but to whom the acts of a third party are attributable because they are an instigator, accomplice, or accessory (Belkin v Philips). This principle confirms the possibility of joint liability for patent infringement at the UPC.
Liability of managing directors
As set out above, the Court of Appeal held that an “infringer” includes someone who does not himself carry out the infringing acts but to whom the infringing acts of a third party are attributable because she is an instigator, accomplice, or accessory to the infringing acts (Belkin v Philips). The Court of Appeal acknowledged that a managing director may be liable for patent infringement as an instigator, accomplice, or accessory but went on to say the “mere position” of managing director does not inherently make a director an accomplice or accessory to a patent infringement.
A managing director may be held liable if her actions go beyond her professional duties in managing the entity. For example, if she deliberately uses the company to commit infringements. Another example is where the managing director knows that the company is committing patent infringement and she fails to take action to stop it. This requires two parts: awareness of the circumstances giving rise to the patent infringement and awareness of the illegality of the use (Align v Angelalign).
Importantly, if a managing director seeks legal advice on the matter, they can generally rely on non-infringement advice until a first-instance decision has been issued establishing the patent infringement. This provides a degree of protection for directors who have acted in good faith based on professional advice (Belkin v Philips).
Consumables
In an important consumables case, Canon sued Katun for selling “developer supply containers” (i.e. toner bottles) that can be used in Canon printers (Canon v Katun). Katun argued that the claims covered the developer supply containers when they are connected to copiers having the necessary “developer receiver apparatus” with a “receiving portion”. In contrast, Canon argued the claims covered only the developer supply containers.
The key wording of the claim was:
A developer supply container detachably mountable to a developer receiving apparatus (8) including a developer receiving portion (11) provided with a receiving opening (11a) for receiving a developer, and a supported portion (11b) integrally displaceable with the developer receiving portion (11),
Applying long-established construction principles, the Court determined that the developer receiving apparatus itself (i.e. the printer), is not the subject of claim 1. Claim 1 only states that the developer supply container is “mountable” to a developer receiving apparatus. The skilled person would understand that parts of the developer receiving apparatus are not claimed to be present and the developer supply container only has to be suitable to be detachably mounted on a developer receiving apparatus as described in claim 1. As a result, the Court found direct infringement of claim 1 by all defendants.
Indirect infringement
Article 26 UPCA addresses indirect infringement, which occurs when a party supplies or offers to supply “means relating to an essential element of [a patented] invention” to persons who then use those means to infringe the patent:
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.
This provision enables a patentee to bring proceedings against a third party who is not themselves performing an act of direct infringement, for example is not themselves making or offering the patented invention, but who is providing means relating to an essential element of the invention to another person to work the invention.
In Brita v Aquashield, the Court defined “means relating to an essential element” broadly: any component that functionally interacts with one or more features of the patent claim in the realisation of the protected invention is an “essential element” of the invention. The Court expressly did not limit the scope to elements relating to the “core” of the invention or ones that distinguish the claim from the prior art. The Court further held that, since the claims are decisive for determining which subject matter is protected, all features specified in a patent claim are usually considered essential elements of the invention (Brita v Aquashield). This decision is addressed in more detail below.
Subjective knowledge requirement
Indirect infringement has a subjective knowledge component that distinguishes it from direct infringement. The alleged indirect infringer must know, or it must be obvious to them, that the means are suitable and intended for putting the invention into effect.
Staple commercial products
Article 26 provides an exception to “means relating to an essential element of that invention”, namely “staple commercial products” which are not covered unless a third party induces the person supplied to perform an act of infringement. As a result, third parties are generally free to supply products commonly found in trade, unless the third party is also encouraging performance of an act of direct infringement.
Marketing consumables
In an important decision briefly referred to above, Brita, the water filtration company, successfully asserted its patent covering a water filter jug against Aquashield which distributed cartridges marketed as compatible with Brita filter jugs (Brita v Aquashield).
Brita’s invention provided a valve system preventing water from flowing into the filtered water container unless a filter cartridge was installed in the filter jug. The mechanism worked by the filter cartridge having a “valve actuating device” that, once installed, opened the valve by exerting horizontal force and then filtered water could pass through.
Aquashield’s counterclaim for revocation was partially successful and as a result Brita’s amended claims were directed only to a complete water filter system rather than solely to the valve actuating device. Aquashield accepted that its cartridges included valve actuating features; but argued that it could not infringe because it was not selling complete filter systems.
The Court held that Aquashield did not infringe under direct infringement. Turning to indirect infringement, the issue was whether Aquashield’s filter cartridges were a “means relating to an essential element of that invention” and therefore liable for indirect infringement. The Court found that the water filter cartridges indirectly infringed the patent. As set out above, the Court defined the “means relating to an essential element” broadly to include any component that functionally interacts with one or more features of the patent claim in the realisation of the protected invention is an “essential element” of the invention. Applying this law to the facts of the case, the Court found that Aquashield’s filter cartridges, which include valve actuating features, are essential means to Brita’s invention because they are responsible for treating the water, which is the purpose of the invention embodied in Brita’s water filter jug.
Doctrine of equivalents
Whilst the UPCA does not expressly codify a doctrine of equivalents, the Court of First Instance confirms that equivalence should be considered when assessing the scope of patent protection, as indicated by Article 2 of the Protocol on the Interpretation of Article 69 EPC which makes clear that equivalents must be considered when assessing scope of protection (Plant-e v Arkyne).
The Hague LD in Plant-e v Arkyne articulated a four-part test for assessing infringement by equivalence, which has been applied in subsequent cases:
This entails that a variation is equivalent to an element specified in the claim if the following four questions are answered in the affirmative.
1) Technical equivalence: does the variation solve (essentially) the same problem that the patented invention solves and perform (essentially) the same function in this context?
2) Fair protection for patentee: Is extending the protection of the claim to the equivalent proportionate to a fair protection for the patentee?
3) Reasonable legal certainty for third parties: does the skilled person understand from the patent that the scope of the invention is broader than what is claimed literally?
4) Is the allegedly infringing product novel and inventive over the prior art?
The Hague LD found that Plant-e’s patent was valid and infringed by equivalence even though there was no literal infringement of the claims.
This area of law is developing rapidly and will likely require a Court of Appeal decision to settle the legal test. Indeed, in Washtower v Wasombouw, the UPC explained, in obiter, that developing a harmonised approach to equivalents “inspired on the doctrines of equivalence applied across UPC Contracting Member States” is “desirable”. In a February 2026 decision, the Court of First Instance described that to find technical-functional equivalence, the substitute should fulfil the same function in order to achieve essentially the same effect (Messerle v Sabert).
Conclusion
The UPC has made significant strides in developing a coherent body of patent infringement law in its first few years of operation. Direct infringement under Article 25 UPCA has been interpreted broadly, with the Court of Appeal confirming that “offering” encompasses economic rather than strictly legal concepts, and that liability can extend to instigators, accomplices, and accessories; including managing directors who knowingly fail to prevent infringement.
Indirect infringement under Article 26 UPCA has similarly received judicial attention, with the Court adopting a broad interpretation of what constitutes "means relating to an essential element" of an invention. The Brita v Aquashield decision demonstrates that suppliers of compatible consumables may face indirect infringement claims where their products functionally interact with patented features.
As the UPC continues to mature, its decisions will shape the landscape of patent enforcement for years to come. Rights holders and potential defendants alike should remain attentive to these developments as the Court refines its approach to infringement.