2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/163290We provide a characterization of $J$-class and $J^{mix}$-class unilateral weighted shifts on $l^{\infty}(\mathbb{N})$ in terms of their weight sequences. In contrast to the previously mentioned result we show that a bilateral weighted shift on $l^{\infty}(\mathbb{Z})$ cannot be a $J$-class operator.We correct some of the statements and the proofsFunctional AnalysisDynamical Systems47A16 (Primary); 37B99, 54H20 (Secondary)text