We consider parallel multi-machine scheduling with due times, where a partition of jobs is given where jobs in the same partition have a common release time, possibly precedence constraints, and cannot overlap. A formulation of decision diagrams for this problem greatly improves upon a more natural extension of the state-of-the-art for single-machine scheduling, and can provide decent lower bounds, outperforming existing solvers given the same short runtime limit, for problem instances with large time scales and tight due times.