Secure access to inventory data concerning a supplier's product located at a seller's premises is provided by tagging units of product with a supplier identifier and a product identifier. The identifiers may be embedded in RFID tags or EPC labels. A secure VPN tunnel is established between a supplier and a seller. The VPN tunnel is associated with a particular supplier identifier such that only inventory data associated with the supplier identifier that matches the supplier is transmitted on the VPN tunnel, and inventory data associated with supplier identifiers that do not match the supplier are filtered out. Hence, the seller can provide the supplier with access to inventory data without exposing sensitive information related to the seller and other suppliers.