Systems and methods for network asset lifecycle management are described. Network assets may include ephemeral Internet-accessible assets such as IP addresses, domain names, digital certificates, and cloud infrastructure accounts. A set of addresses associated with a computer network such as the Internet are scanned. Response data is received from one or more network systems connected to the computer network and processed to identify one or more network assets associated with an entity such as an enterprise organization. Asset data indicative of the identified network assets are then stored to build a record of the network assets associated with the entity.