Atomically Trading with Roger: Gambling on the Success of a Hardfork

  • Patrick McCorryEmail author
  • Ethan HeilmanEmail author
  • Andrew MillerEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10436)


We present atomic trade protocols for Bitcoin and Ethereum that can bind two parties to swap coins in the event that two blockchains emerge from a single “pre-fork” blockchain. This work is motivated by a bet between two members of the Bitcoin community, Loaded and Roger Ver, to trade 60,000 bitcoins in the event that Bitcoin Unlimited’s planned hardfork occurs and the blockchain splits into two distinct forks. Additionally we study several ways to provide replay protection in the event of hardfork alongside a novel mechanism called migration inputs. We provide a detailed survey and history of previous softforks and hardforks in Ethereum and Bitcoin.



We thank Nick Johnson for bringing to our attention hardfork oracles, Tadge Dryja for his comments and criticisms, Roger Ver for allowing us to use his name in the paper’s title, Iddo Bentov for insightful discussions and #bitcoin-wizards IRC channel for answering questions regarding forks. Patrick McCorry is supported by EPSRC grant EP/N028104/1, Ethan Heilman is supported by NSF 1350733.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.University College LondonLondonUK
  2. 2.Boston UniversityBostonUSA
  3. 3.University of Illinois at Urbana-ChampaignChampaignUSA
  4. 4.Initiative for Cryptocurrencies and ContractsBerkeleyUSA

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