Recently, aspernigrin A (1a), which had previously been described by us from a sponge-derived Aspergillus niger, was reisolated from an endophytic Cladosporium herbarum by Ye et al. On the basis of X-ray crystallographic analysis, the authors revised the 2-pyridone substructure initially proposed for aspernigrin A (1b) to a 4-pyridone (1a), also reassigning 13C NMR signals for C-4 (δ 178.1), C-6 (δ 151.2), and C-14 (δ 165.9) (originally assigned by us as C-14, C-4, and C-6, respectively). Our misinterpretation of the 13C NMR data led to misinterpreting a 4J correlation in the HMBC spectrum from H-5 to C-14 as a 2J correlation from H-5 to C-6, resulting in the wrong structure 1b. Based on the X-ray crystal structure of 1a and nearly identical NMR data for the 4-pyridone moiety, the planar structure of 2 should likewise be revised to a 4-pyridone (2), with corresponding exchange of three downfield 13C NMR signals (δ 176.1 for C-4, δ 164.5 for C-14, δ 151.7 for C-6) and revision of one HMBC correlation for H-5 to C-14 (instead of C-4). Since different authors contributed to different aspects, R. Ebel takes full responsibility for the structure revision of aspernigrin A (1a) and B (2).