Data-Centre Sustainability Reporting Under EU Law: Confidentiality, Operator Publication, and Access to Information

European Union (EU) data-centre sustainability reporting combines operator publication, an aggregated public database, and access to information held by public authorities. Article 5(5) of Delegated Regulation (EU) 2024/1364 classifies individual reported information as confidential, creating uncertainty where these routes overlap. This paper presents doctrinal analysis of the Energy Efficiency Directive, EU access legislation, judgments, reporting definitions, and the Commission’s complete October 2025 access decision. It supports an information-based classification with consequences determined by each disclosure framework. Database context limits the rule’s scope, but relocating identical information does not in itself defeat protection. Equally, confidentiality does not displace the applicable public-interest and emissions conditions. Calculated indicators require a reasoned assessment of practical reconstruction, including available variables, matching boundaries and periods, derivation difficulty, and meaningful precision. Environmentally relevant information about energy or water use does not necessarily constitute emissions information. Operators must distinguish protected information from other material covered by their publication duty. Reasons and review can expose unlawful withholding without necessarily supplying the public with evidence sufficient to check facility performance. The present analysis clarifies how confidentiality, disclosure, and review jointly shape public scrutiny, without presuming actual disclosure, mandatory independent assurance, or environmental improvement.