OK, I guess there is Bitcoin and Ethereum in the permissionless world. Also, of note are:
- Fabric — Incubated by the Linux Foundation’s Hyperledger Project. It is based on significant early contributions from IBM and Digital Asset Holdings.
- Sawtooth Lake — Also incubated by the Hyperledger Project, it was submitted by Intel. It was originally developed to explore scalability, security, and privacy issues.
- Corda — Developed by R3 CEV, it will be submitted to the Hyperledger Project on November 30.
- Quorum — Developed by JPMorgan Chase, it is a fork of Ethereum but suitable for both permissionless and permissioned blockchains. JPMC says it plans to open source it.
- Chain Core Developer Edition — an open source version of its enterprise blockchain product. It can be run on a test network operated by Chain, Microsoft and IC3.
- Iroha — another distributed ledger being incubated by the Hyperledger Project, Iroha was developed by Japan’s Soramitsu and is targeted at C++ developers and mobile applications.
Also, Digital Asset Holdings is planning to open source its Digital Asset Markup Language (DAML) for smart contracts, and is also suggesting that its Global Synchronization Log — a component of its own distributed ledger platform — might find a use within one or more of the Hyperledger Project’s developments.