Reproducibility of Thermodynamic Stability and Band-Gap Screening of Inorganic Materials Across Materials Project Versions

High-throughput computational databases have become central to the discovery and screening of inorganic materials, yet the reproducibility of candidate selection across database versions has rarely been quantified. Here, a frozen 2018 Materials Project snapshot was harmonized with database version 2026.04.13 to evaluate the cross-version stability of thermodynamic and electronic screening. Among 78,756 historical mp-* records in the primary longitudinal cohort, 76,931 remained traceable (97.68%). Despite high cross-version property rank agreement, screening reversal rates ranged from 1.2% to 8.1% across the 16 combined threshold pairs. Under the representative criterion Ehull ≤ 0.05 eV·atom−1 and Eg ≥ 2 eV, 15,754 materials were selected in 2018 and 14,191 in 2026; 1818 original candidates exited and 255 entered, corresponding to 88.46% candidate retention and a Jaccard similarity of 0.871. Instability was concentrated near decision boundaries and remained chemically structured after multivariable adjustment. Cl-, Br-, and N-containing materials were dominated by energy-above-hull threshold crossings, whereas the 3d-series metal group showed a larger contribution from band-gap changes. These results distinguish property reproducibility from decision reproducibility: strong cross-version property agreement does not guarantee stable candidate sets. The database version should therefore be treated as essential reproducibility metadata in high-throughput inorganic materials screening.