AUTHOR=Berg Chris , Davidson Sinclair , Potts Jason TITLE=Proof of Work as a Three-Sided Market JOURNAL=Frontiers in Blockchain VOLUME=Volume 3 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/blockchain/articles/10.3389/fbloc.2020.00002 DOI=10.3389/fbloc.2020.00002 ISSN=2624-7852 ABSTRACT=Blockchain technology is the distributed, decentralised ledger technology underlying Bitcoin and other cryptocurrencies. We apply Oliver Williamson’s transactions cost analysis to the blockchain consensus mechanism. Blockchains reduce the costs of opportunism but are not ‘trustless’. We show that blockchains are trust machines. Blockchains are platforms for three-sided bargaining that convert energy-intensive computation into economically-valuable trust.