Brazilian federal environmental infraction records linked to firm industry classification 1981 to 2025

We present a curated dataset of Brazilian federal environmental infraction notices issued to corporate entities, linked to establishment-level industry classification using Brazil's National Classification of Economic Activities. The release covers 1981–2025 and comprises 225,635 corporate infraction records, provided as a primary analytical table containing infraction notice attributes, corporate identifiers, primary and secondary CNAE codes with hierarchical descriptors, and municipality-level georeferencing. Technical validation outputs quantify match rates, CNAE coverage, and industry classification stability across registry snapshots. Version 2.0 supersedes version 1.0 following peer review. Changes: the temporal window (1981–2025) is now applied exactly once; CNAE snapshot selection follows a deterministic modal rule; four variables have been added (cnpj_root, cnpj_dv_valid, cnae_snapshot_unstable, primary_legal_provision); the legal basis field (legal_framework) has been restored; the offender name field has been withheld from the release. Row identifiers (record_id) were regenerated and are not comparable across versions. Code and documentation for the full processing workflow are available at https://github.com/cruz-neto/DataPaper (tag v2.0).