The Impostrip Book Stacker was designed to make parallel book blocks of varied lengths on a digital press to minimize cutting and folding, and optimize paper and impression time by putting the maximum number of blocks together without operator intervention. Key features of the product include: barcode output on each sheet and each stack to drive Duplo cutters for automatic cutting of the stacks; timed printing so jobs can accumulate for optimization and be printed when desired; and an automatically generated Banner Sheet that is inserted between stacks to identify each of them. A Banner Sheet can contain custom information, including barcodes, so each stack can be easily identified and tracked to ensure delivery to the appropriate customer.