Claim Construction and Multi-Material Purge Towers at The Hague Local Division
The Hague Local Division dismisses an application for provisional measures, strictly interpreting a 'layer by layer' claim feature based on the patent's description and drawings.
The interpretation of patent claims under Article 69 EPC at the Unified Patent Court has been firmly anchored by the Court of Appeal's NanoString principles, which mandate that the description and drawings must always be used as explanatory aids. The Hague Local Division's recent order in UPC-CFI-305/2026 applies this framework to strictly limit a structural claim feature based on the specification's teaching, demonstrating exactly how these principles operate to defeat an application for provisional measures.
The purge tower and feature 1.4.1
The applicant, Stratasys, sought a preliminary injunction against Bambulab for indirect infringement of EP 2 964 450. The patent addresses the inefficiencies of multi-material 3D printing by replacing a conventional purge station with a "purge tower" printed directly on the build platform.
The infringement dispute hinged entirely on the interpretation of feature 1.4.1, which requires "the purge operations comprising printing at least one purge tower in a layer by layer manner". Bambulab argued that the skilled person would understand this to mean horizontal layers where each subsequent layer is printed on top of the previous one. Stratasys advocated for a broader interpretation, arguing the claim does not prevent layers from being placed next to each other horizontally.
Claim construction through the specification
Applying the Court of Appeal's guidance, the panel rejected the broader interpretation. The judges noted that the patent teaches that each layer of the purge tower is printed by either the part material or the support material depending on when the print heads switch modes.
Relying on the general meaning of "layer" as a flat strip, the panel found confirmation in Figure 6 and the description, which illustrate that each horizontal layer of the purge tower consists of one type of material only (reasons 32). Because the patent teaches that each layer is preferably printed along the same tool path, the panel concluded that the skilled person will therefore understand 'layer-by-layer' of feature 1.4.1 to require that with each purge operation a new horizontal layer of the purge tower is created (reasons 35). Consequently, a tower with horizontal layers consisting of different materials next to each other in the same plane falls outside the scope of protection.
The multi-material boundary line
This precise construction proved fatal to the infringement case. Bambulab's H2C printer generates a "prime tower" featuring a boundary line printed from the material the model uses most, designed to ensure the structural integrity of the prime tower.
Because this boundary line encloses the inner infill, a single horizontal layer of the accused prime tower contains both part material and support material at the same level (reasons 40). Since the accused product does not perform layer-by-layer printing where each layer consists of one type of material, the panel found it more likely than not that the patent is not infringed, dismissing the application under Rule 211.2 RoP.
Procedural boundaries for minute takers
In a notable procedural aside, the panel blocked unannounced "minute takers" from participating online during the oral hearing. Stratasys objected to their presence, and the panel agreed, noting that it lacked control over the online participation, which resembled an unpermitted recording by a party (reasons 21). The panel explicitly distinguished this from the Court of Appeal's Amazon/InterDigital order, which permits a private transcript based on an official audio recording pursuant to Rule 115 RoP, rather than live transcription by remote third parties.
Practical implications
This order provides a clear example of how the Unified Patent Court uses the description to establish the boundaries of a claim. Practitioners drafting or litigating claims with seemingly broad structural terms (like "layer by layer") must ensure that the specification actually supports the broader reading. If the drawings and description only disclose a single-material horizontal strip, the Court will likely restrict the claim to that specific arrangement, regardless of whether the bare words of the claim could theoretically encompass side-by-side material placement.
Procedurally, the decision also confirms that if parties agree on an interim costs award—here, EUR 112,000, the ceiling for a EUR 1,000,000 case value—the panel can embed this directly into the order dismissing the application for provisional measures, avoiding the need for separate cost proceedings. Furthermore, parties wishing to use live transcribers during an oral hearing must ensure they are physically present in open court, as remote, unannounced minute-taking will not be tolerated.