Patent attributes
This disclosure describes a system for managing inventory as it transitions into a materials handling facility, as it transitions between locations within a materials handling facility and/or as it transitions out of a materials handling facility. In some instances, a total weight associated with a user pattern may be monitored by sensors of a base surface and weight of inventory items may be monitored by sensors at the inventory locations. When a user associated with the user pattern retrieves an item from an inventory location, the decrease in the weight at the inventory location will correspond with the increase in total weight associated with the user pattern. Accordingly, the item may be tracked from the inventory location and associated with the user pattern based on the corresponding changes in weight.