US Patent 11803847 Secure control of transactions using blockchain

Technologies are shown for controlling a transaction on a digitally stored blockchain by creating a contract data block for a transaction involving entities and by event code executed after receipt of digital signatures from the entities. A refund transaction may be digitally signed by entities and linked to the contract block within the blockchain. A payment transaction block may also be digitally signed by entities and linked to the contract block. Code authorized to execute by the blocks executes based on receipt of digital signature events.