UPC_CFI_660/2025 – Steros v Otec

Court
Local Division Hamburg
Date
Outcome
Denied
Sector
Chemicals
Decision Type
MERITS

Expert Commentary

Infringement case Facts 1. Steros sued Otec for infringement of EP 4 249 647 for an Electrolytic Medium and Electropolishing Process using such Medium. 2. The Court of Appeal rejected the application for provisional measures (after they had been granted and enforced in first instance). The Court 1. The Court discussed the patent, defined the skilled person and interpreted claim 1 after citing all the applicable principles. 2. The Court held, with respect to the interpretation of the claim element “non-conductive fluid”, which is (only) described by its physical properties (“immiscibility with the conductive fluid and no significant conductivity”): “Therefore, the non-conductive fluid is not defined by a specific formula or substance class. However, the person skilled is aware that not every substance exhibiting the aforementioned physical properties is covered by the scope of protection of the patent-in-suit, but only those that are suitable for performing the function of the invention, because the technical interpretation of the terms used in the patent claim is determined primarily by the purpose of the feature described by those terms, as expressed in the patent specification. Based on the wording, the technical and functional meaning of the feature must be determined as it applies in the context of the invention. A function-based interpretation is, in any case, appropriate if the wording of the patent claim does not, on its own, allow for a clearly defined understanding. For just as with spatially and physically described features of a patent claim—where a functional interpretation cannot prevail over the spatially and physically described features—so too, in the case of features described solely by their physical properties, their technical function, as intended by the patent, may not be disregarded. Otherwise, the scope of protection would be limited solely by the physical properties of a material specified in the claim, without it being possible to achieve the result of the invention.” 3. The conclusion of this claim interpretation is that the term “non-conductive fluid” is limited to water-in-oil emulsions. The defendant uses an oil-in-water emulsion and therefore does not infringe. 4. While citing the case law of other Divisions with respect to costs of a conditional counterclaim, the Court deviated from these decisions and stated that parties have to bear their own costs. Comment 1. After the correction by the Court of Appeal, the LD Hamburg, now comes to the correct result in a different way, based on an interpretation of the claim elements (see above), which I think is absolutely correct. 2. Unfortunately, as I have already stated several times before, in my opinion the cost decision is incorrect. Mannheim and Paris (unlike Munich) showed the way it should be done. Forget about formalities such as the fact that proceedings for infringement and revocation are distinct, and be realistic. Why does the defendant in the infringement case file a conditional counterclaim? There can be only one reason, which is triggered by the fact that claimant chose to accuse it of infringement. The defendant filed it (or rather: was forced to file it) as a defence alongside several other arguments as to why the defendant did not infringe. The defendant won. So the defendant should be reimbursed for its costs!

Key Holdings

  • The technical interpretation of terms used in a patent claim is determined primarily by the purpose and technical function of the feature described by those terms, as expressed in the patent specification.
  • A function-based interpretation is appropriate where claim features are described solely by their physical properties, meaning only substances suitable for performing the intended technical function of the invention fall within the scope of protection.
  • With respect to the costs of a conditional counterclaim, the Court held that parties must bear their own costs, deviating from decisions of other Divisions.

Tags

  • Infringement case
  • Claim interpretation
  • Functional interpretation
  • Non-infringement
  • Costs
  • Conditional counterclaim

Related Cases

View original decision