Business Insider obtained a copy of the US patent, filed on May 10, for a passcode blockchain that Verizon has apparently been working on for three years. The patent relates to digital content — think an e-book or a digital-music or video file.
According to the filing, “The DRM (digital rights management) system may maintain a list of passcodes in a passcode blockchain. The passcode blockchain may store a sequence of passcodes associated with the particular digital content and may indicate a currently valid passcode. For example, a first passcode may be assigned to a first user and designated as the valid passcode. If the access rights are transferred to a second user, a second passcode may be obtained and added to the blockchain, provided to the second user, and designated as the valid passcode. Thus, the first passcode may no longer be considered valid.”
Source: Verizon filed for a blockchain patent – Business Insider