Looking for permissioned blockchain for company governance and equity accounting with ability to interact with cryptocurrencies (permissionless blockchains), ie. sale some stake for ether. Could proof-of-authority based solution be used in this case, and what are general pitfalls? Is there some complete solutions with UI aimed to company governance task, eg. initiate proposals, voting, dispute tracking ..?
Have a look at https://www.jpmorgan.com/global/Quorum Quorum is a Enterprise-ready distributed ledger and smart contract platform which is based on ethereum. Quorum has some additional features like. It can send private transactions and restrict their delivery without breaking the blockchain; this ensures your data is only routed to its intended recipient – and no one else.
I hope that helps.