How Does the UPC Assess Equivalence? — Reflections on Wonderland v. Cybex

The UPC has added another noteworthy decision on infringement by equivalence.

On 27 May 2026, the Local Division Düsseldorf delivered its judgment in Wonderland v. Cybex (UPC_CFI_807/2024, UPC_CFI_334/2025). The Court upheld the patent but found no infringement, either literally or by equivalence.

The judgment is noteworthy because it expressly endorses the four-step framework developed by the Local Division The Hague while providing further guidance on its practical application.

1. The Court Endorses the Four-Step Framework Developed by the Local Division The Hague

The UPC Court of Appeal has not yet established a uniform test for infringement by equivalence.

In Plant-e v. Arkyne, the Local Division The Hague formulated a four-step framework, which it later applied again in Washtower v. BEGA.

In Wonderland v. Cybex, the Düsseldorf Local Division expressly endorsed that approach, stating:

“The criteria set out by the Local Division The Hague form a coherent whole.”

The Court therefore considered the four-step framework suitable for assessing infringement by equivalent means and found no reason to adopt a different standard in the present case.

Under this framework, the Court asks four questions:

1. Does the variant perform essentially the same technical function as the claimed feature (technical equivalence)?

2. Would extending protection to the variant provide fair protection for the patentee, taking into account, among other things, whether the equivalent would have been obvious to the skilled person from the patent?

3. Would such an extension remain consistent with reasonable legal certainty for third parties?

4. Is the alleged equivalent itself novel and inventive over the prior art (the Formstein/Gillette defence)?

2. The Same Overall Technical Objective is Not Enough

Perhaps the most significant part of the judgment concerns the Court’s discussion of technical equivalence.

The patentee argued that the accused product merely rearranged the locations of several claimed components.

For example, the claims required the locking pin to be disposed on the wheel bearing assembly, whereas the accused embodiment located the locking pin on the seat. Likewise, the operating member was coupled to the seat rather than the wheel bearing assembly, and the cavity and clasping mechanism were likewise relocated.

According to the patentee, these modifications did not change the overall technical objective of the invention, namely providing a stable connection between the rotatable and non-rotatable parts while allowing selective locking of the swivel mechanism.

The Court disagreed.

Referring to Headnote 2, the Court explained that a patentee cannot establish technical equivalence simply by focusing on the overall objective of the invention. Instead, it must identify the function performed by each substituted claim feature and explain why the modified feature performs essentially the same function.

This was particularly important because the patent expressly claimed not only the components themselves, but also their specific arrangement. The Court observed that the patentee had not explained why the claimed arrangement, such as locating the locking pin and operating member on the wheel bearing assembly, and placing the cavity and clasping mechanism within the wheel bearing assembly, was functionally equivalent to the modified arrangement adopted in the accused product.

The Court therefore concluded that technical equivalence had not been established.

3. Why the Variant Was Not Obvious to the Skilled Person

The Court next considered the second step of the analysis: fair protection for the patentee.

The patentee argued that the skilled person could arrive at the accused embodiment simply by reversing the operating direction of the locking pin and relocating the relevant components. During the oral hearing, it even submitted that the claimed arrangement merely had to be turned by 180 degrees.

The Court disagreed. It held that implementing the accused embodiment required several interrelated claim features to be rearranged simultaneously, amounting to a complete redesign of the claimed device.

Headnote 3 therefore states:

“In general, it is not obvious to a skilled person how to apply the equivalent element if a complete redesign of the claimed device is required.”

Importantly, the Court did not hold that every structural modification constitutes a complete redesign. Rather, it reached that conclusion on the particular facts before it, where multiple interrelated structural relationships defined by the claims had to be altered simultaneously.

4. The Court Also Considered Legal Certainty

Another noteworthy aspect of the judgment is that the Court continued its analysis even after concluding that the first two requirements were not satisfied.

The Court went on to consider reasonable legal certainty for third parties.

It observed that the patent did not merely claim a general technical concept or functional result. Instead, the claims specified a particular structural arrangement, including where the locking pin, operating member, cavity and clasping mechanism were located.

Accordingly, a skilled person reading the patent would understand that these structural relationships formed part of the claimed technical solution rather than representing arbitrary design choices.

Extending protection to an embodiment that altered several of those structural relationships would therefore undermine the reasonable expectations of third parties as to the scope of protection.

The Court therefore concluded that the third step of the Hague framework was likewise not satisfied.

5. How does Wonderland v. Cybex Fit into the UPC’s Developing Case Law?

Plant-e v. Arkyne was the first UPC decision to formulate and apply the four-step framework, while Washtower v. BEGA subsequently applied it in preliminary injunction proceedings.

By contrast, decisions such as OrthoApnea, DISH v. AYLO, N.J. Diffusion v. Gisela Mayer and Hartmann Packaging v. Omni-Pac turned largely on technical equivalence and therefore did not require a detailed analysis of the remaining steps.

Against that background, Wonderland v. Cybex stands out because it is the first decision of a German Local Division to endorse the Hague framework. It also clarifies two important aspects of that framework: technical equivalence must be assessed feature by feature, and, in general, a variant requiring a complete redesign of the claimed device will not be obvious to the skilled person.

Whether the Court of Appeal will ultimately endorse the Hague framework—or refine it further—remains to be seen.





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