A method for maintaining state and event information for all of a user's devices associated in a common location using a blockchain where each block includes an event block and a device block within it, where each event and device block refers to an earlier block of the respective type, resulting in a blockchain-in-a-blockchain architecture. The device and event blocks store data regarding each device associated with a user and events related to the devices/user, respectively. Any time a new event occurs, or a device is registered or removed, a new set of blocks is created, where submissions regarding device changes or events can be made by any participant due to the decentralized and public nature of a blockchain. The result is a system where all data regarding a user's registered devices and events is kept in a common location in a manner that is auditable and verifiable.