Metadium is developing a blockchain protocol for Self-Sovereign Identity. Their goal is to allow users to own all aspects of their identity. Metadium's network is powered by the Ethereum-based META token.

Aston is a decentralized document distribution network that enables users to better control their personal documents and professional certifications. It records, authenticates, and distributes identifying documents and information, and integrates biometric identification to ensure security.
Aston's platform is based on X-Chain architecture, which has a hybrid consensus mechanism. It combines a Proof of Forkability (PoF) mechanism with a Distributed Proof-of-Stake (dPoS) consensus protocol that stores and distributes data in 3rd dimension sub-chains.
The network is powered by the ATX coin.

uPort is developing a self-sovereign identity platform for the Ethereum blockchain. It will consist of a wallet that will allow users to sign transactions and manage their keys and data more easily, as well as tools that will allow developers to issue credentials and request data from other DApps that use the paltform. uPort is a ConsenSys portfolio company.