A method begins by a dispersed storage (DS) processing module identifying, by a first storage unit of a dispersed storage network (DSN), an encoded data slice for transfer to a second storage unit of the DSN. The method continues by the first storage unit determining whether the encoded data slice is part of a fan-out encoded data slice group and, when it is part of a fan-out encoded data slice group by the first storage unit sending an encoded data slice transfer message to the second storage unit. The encoded data slice transfer message includes the encoded data slice and information regarding the fan-out encoded data slice group. The second storage unit stores the encoded data slice and generates copies of the encoded data slice based on the fan-out encoded data slice group and stores the copies of the encoded data slice.