The Limits of Plethoric Submissions: T 0867/24 on Clarity and Conciseness
A 143-page reply to an appeal backfires as the Technical Board of Appeal uses Article 12(5) RPBA to exclude a scattergun array of inventive step attacks.
The procedural requirements governing the admissibility of submissions have steadily tightened since the revised Rules of Procedure of the Boards of Appeal took effect. While practitioners typically focus on the strict deadlines for filing new requests or experimental data, T 0867/24 shifts the focus to a different procedural obligation, namely the fundamental duty under Article 12(3) RPBA to present arguments clearly and concisely.
The 143-page reply
The appeal concerned a nasal composition comprising a saline base, an active agent, and a mixture of a first hyaluronic acid with a second hyaluronic acid having specific molecular weight ranges. The opposition division had revoked the patent for lack of inventive step. In response to the patent proprietor's appeal, the opponent filed a 143-page reply.
The Technical Board of Appeal found this submission to be overly repetitive, poorly structured, and burdened with irrelevant or tangential arguments. The opponent had restated basic case law principles at length without a clear link to the case, duplicated objections using family members of cited documents, and presented a plethoric case of inventive step attacks. Specifically, the opponent combined the closest prior art with dozens of secondary documents, often without applying a proper problem-solution approach.
Enforcing clarity and conciseness
The panel took a strict approach to these sprawling submissions. The board held that the requirements for clarity and conciseness of Article 12(3) RPBA preclude the presentation of arguments that are either confusing or unnecessarily protracted, to the extent that potentially relevant objections or requests risk being obscured within an overabundance of extraneous or repetitive content (reasons 1.1).
Crucially, the board noted that it is not the task of the opposing party or the board to investigate which objections within a host of poorly substantiated attacks are the most compelling. The right to be heard under Article 113 EPC does not allow a party to present their case in a way that makes the opposing party's exercise of their own right to be heard impossible. Consequently, applying its discretion under Article 12(5) RPBA and Article 12(4) RPBA, the board refused to admit the vast majority of the opponent's inventive step attacks, limiting the proceedings to attacks starting from the primary prior art document and a handful of specific secondary documents.
The burden of proof for comparative data
Turning to the substantive assessment of inventive step, the patent proprietor relied on experimental data to demonstrate an improved film-forming effect over the closest prior art. However, the composition representing the claimed invention contained the surfactant alkyl polyglucoside, whereas the composition representing the starting point did not.
The board found that the experimental data did not meet the required standard. If a patent proprietor alleges that the claimed invention improves a technical effect, the burden of proof rests upon them to show that the advantage convincingly has its origin in the distinguishing feature. Because the difference in film-forming characteristics could be the consequence of the surfactant rather than the claimed dual-fraction hyaluronic acid mixture, the objective technical problem was formulated merely as the provision of an alternative nasal composition. The claimed solution was found obvious in light of prior art disclosing topical compositions with the same bimodal hyaluronic acid mixtures.
Practical implications
This decision establishes a clear procedural boundary for respondents in appeal proceedings. A scattergun approach to defending a revocation decision, where every conceivable combination of prior art is thrown at the board in a massive submission, is not merely poor advocacy but a procedural defect under Article 12(3) RPBA. Boards will not sift through hundreds of pages to find the strongest attack, and they will actively use Article 12(5) RPBA to exclude unnecessarily protracted or confusing arguments.
Substantively, the decision reinforces the strict requirements for comparative data. When relying on an improved technical effect to establish an inventive step, practitioners must ensure that the tested compositions differ only in the distinguishing features. If the inventive example contains additional components like a surfactant that are absent from the comparative example, the board will not assume those components are inert. The burden remains entirely on the patent proprietor to prove that the observed effect originates exclusively from the claimed features.