Nxt is a blockchain platform developed by Jelurida, which is also developing the Ardor blockchain. Nxt's goal is to improve upon existing blockchain platforms with a modular toolset that enables users to create their own digital assets that can be listed on decentralized marketplaces. Nxt also features community driven voting mechanisms and has an architecture that separates the blockchain into parent and child blockchains.
The network is powered by the NXT token and has a Proof-of-Stake (PoS) consensus mechanism.

Lisk is a blockchain-based platform that allows developers to build and publish their own applications. Lisk uses sidechain development kits, that are written in Javascript, to enable users to create their own blockchain applications according to their needs. Each decentralized App runs on its own sidechain that can be customized, and is connected to the Lisk blockchain, which has a Delegated Proof-of-Stake (dPoS) consensus mechanism. The Lisk network is powered by the LSK coin.

Chain is a blockchain software company that creates blockchain-based systems for financial institutions and major companies. They've developed blockchain solutions for companies like Nasdaq, Visa, and Citigroup, as well as a variety of crytpocurrencies. Chain has been successful in incorporating distributed ledger technology in very large and influential companies. Their focus is on using the core innovations of blockchain to improve existing systems. Chain uses blockchain as a software tool that can be applied where it is important for services or product to have more trust, or to build a network without an intermediary