In one embodiment, of inventory management for automated data storage libraries, a first subset of data storage cartridges is scanned and extracted from a multi-cartridge deep slot cell and transported to and filled into another multi-cartridge deep slot cell while maintaining tier order of the first subset. A second subset of data storage cartridges is scanned and extracted from the multi-cartridge deep slot cell and returned to its original multi-cartridge deep slot cell while maintaining tier order of the second subset. Other aspects are described herein.