Executing Collaborative Decisions Confidentially on Blockchains

Decisions are an important aspect of enterprise operations. Decisions cross the boundary of a single enterprise, if multiple business partners collaborate in the decision making. To ascertain that all the participants behave as expected, blockchains can support collaborative decision making by storing relevant data and executing crucial decision logic in a tamper-proof and transparent manner. However, current blockchain technologies require the participants to publish the decision logic and are, therefore, not suited for sensitive data. This paper addresses this issue by proposing an approach that does not need to reveal sensitive data for supporting decision making. However, in case of a conflict, any participant can call for a blockchain-based conflict resolution at the cost of revealing the decision. To counter false claims that purposely reveal the decision, we provide a blockchain-enforced mechanism that discourages malicious behavior. We implement the approach using the Ethereum blockchain and evaluate the costs of resolving conflicts on a large set of decision models.