Align and Carpmaels & Ransford defend PI in dental aligner technology

Partner Arno Riße led the team, with counsel Tim Smentkowski and associate Julius Winkler providing support. On the patent attorney side, Dirk Schulz argued the technical case, assisted by Ulrich Storz and Wanze Zhang. The firms worked with in-house counsel Avery Liu and Lei Dong from Angelalign.In February, the local division Düsseldorf had granted Align a preliminary injunction in the dispute over EP 4 346 690. The patent concerns software for orthodontic treatment planning, specifically Align’s patent covering real-time automated modification of treatment plans for clear aligner therapy.

It was the first preliminary injunction granted by the UPC based on a European Unitary Patent. Now the Court of Appeal panel under presiding judge Ulrike Voß has ruled that EP 690 is likely to be valid and infringed by Angelalign’s iOrtho software and the aligners produced with it.

As a result, the Chinese manufacturer and its European subsidiaries remain barred from distributing the software with its “Live Now” feature and the corresponding aligners in UPC territory (case ID: UPC_CoA_36/2026).

The technology allows dental professionals to modify a treatment plan in real time, with the software checking whether the requested modification stays within predetermined thresholds before generating a revised plan. Align integrated the feature into its ClinCheck software under the name “Live Update” in 2022. Angelalign launched a similar function called “Live Now” in May 2025 with Release 5.2 of its iOrtho software – only weeks before the patent was granted in July 2025.

Claim construction at the centre

The Court of Appeal spent considerable time on the construction of claims 1, 13 and 15, in particular on the interpretation of the determination and generation steps of the claimed method. The judges concluded that these are two distinct steps with a specific temporal order: the software must first determine that a user’s requested modification lies within a predetermined threshold, and only then generate a revised treatment plan. In the panel’s view, this mechanism serves both to save computer resources and to prevent the generation of undesirable treatment plans.

The Court of Appeal rejected all invalidity attacks. The panel also refused to admit two exhibits Angelalign submitted for the first time on appeal, namely a video and an accompanying witness statement intended to demonstrate public prior use of the 3Shape software. The judges held that Angelalign had failed to justify why this evidence could not have been submitted in the first instance, and that admitting it would force Align to defend against a new invalidity attack in a single instance.

Late-filed arguments

A further procedural issue concerned Angelalign’s non-infringement arguments, which the defendant had raised only in its rejoinder at first instance. Düsseldorf local division had disregarded these submissions as late-filed, a decision confirmed by the Court of Appeal in a discretionary review in January 2026.

On appeal, the Court of Appeal partly reversed course. Referring to its earlier case law, the judges noted that uncontested submissions cannot generally be rejected as late-filed and admitted Angelalign’s arguments.

Direct competitors in a niche market

In weighing the parties’ interests, the panel emphasised that Align and Angelalign are direct competitors in clear aligner therapy. The judges found that the continued availability of the infringing software poses a concrete risk to Align’s market position. Clinicians typically commit to one aligner provider for their patients, and the treatment planning software is a relevant factor in that choice. Angelalign itself had prominently featured the “Live Now” function in its marketing materials for Release 5.2.

Parallel opposition proceedings against EP 690 are pending before the EPO, filed by Angelalign among others.

The parties are in dispute over several other patents at the UPC. In May, Düsseldorf local division dismissed a separate PI application by Align concerning EP 4 295 806, which covers a method of designing clear aligners for tooth movement in extraction cases. The panel around presiding judge Ronny Thomas held that Align had not sufficiently established infringement (case ID: UPC-CFI-0001747/2025).

In March, Align filed infringement proceedings on the merits over EP 690 at Düsseldorf local division (case ID: UPC-CFI-0000945/2026). Furthermore, infringement proceedings and a counterclaim for revocation concerning EP 2 237 738 are pending at the Paris local division, with a hearing scheduled for September (case ID: UPC_CFI_684/2025).

Carpmaels vs Arnold Ruess

UK mixed firm Carpmaels & Ransford represented Align in the appeal, as in the first-instance proceedings. Litigator Agathe Michel-de Cazotte led the case, working with patent attorney John Brunner and partner Ian Kirby.

Associates Ben Chapman, Salomé Nattagh, Caroline Horstmann and William Mooney provided support. Carpmaels & Ransford has a long-standing relationship with Align and handles litigation, opposition and other patent matters for the US company.

Düsseldorf-based IP boutique Arnold Ruess represented the five Angelalign entities together with patent attorneys from Michalski Hüttermann & Partner.

Partner Arno Riße led the team, with counsel Tim Smentkowski and associate Julius Winkler providing support. On the patent attorney side, Dirk Schulz argued the technical case, assisted by Ulrich Storz and Wanze Zhang. The firms worked with in-house counsel Avery Liu and Lei Dong from Angelalign.