A most recent Walmart's patent application is dedicated to the blockchain technology, which the retail giant wants to use for communication between automated drones-couriers. A patent application, published August 30, contains a description of the system, in which "an autonomous electronic devices" use wireless communication to transfer data to each other, pass identification and exchange transported objects. After the meeting of two drones at the appointed place, the transmission of the authenticating signals via "blockchain-keys" begins between them. If the robot recognizes a "colleague" successfully, it sends it a package. Drones will take the information from the delivery database, stored in the organization's blockchain. Robots will be able to send signals to each other ― RFID-codes, QR codes, ultrasound, etc. ― with a purpose of identification. In addition, each courier robot can have some unique features, that will simplify its identification by other drones. The patent application also says, that the automated technology usage will accelerate the emergence of "trust" of customers to this type of goods delivery. Walmart's representatives believe, that consumers need to stop worrying about the fact, that their purchases will be delivered by a flying machine. Therefore, company needs a reliable system of drones identification. A blockchain structure, described in the application, consists of many nodes, designed to produce computational proof of data integrity and the content usage chronological order, and to perform trade operations and/or currency exchange in the P2P network. Each node is busy on finding a difficult Proof-of-Work algorithm for its block. According to the representatives of Walmart, the smart contracts can also be added to this structure. Walmart is working actively on various blockchain implementations within its business. For example, the company has recently filed patent applications, which described a way to use the blockchain to manage smart appliances and control the goods delivery.