Smart Contracts for Bribing Miners

  • Patrick McCorry
  • Alexander HicksEmail author
  • Sarah Meiklejohn
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10958)


We present three smart contracts that allow a briber to fairly exchange bribes to miners who pursue a mining strategy benefiting the briber. The first contract, CensorshipCon, highlights that Ethereum’s uncle block reward policy can directly subsidise the cost of bribing miners. The second contract, HistoryRevisionCon, rewards miners via an in-band payment for reversing transactions or enforcing a new state of another contract. The third contract, GoldfingerCon, rewards miners in one cryptocurrency for reducing the utility of another cryptocurrency. This work is motivated by the need to understand the extent to which smart contracts can impact the incentive mechanisms involved in Nakamoto-style consensus protocols.



Patrick McCorry and Sarah Meiklejohn are supported in part by EPSRC grant EP/N028104/1, and Alexander Hicks is supported in part by OneSpan ( and UCL through an EPSRC Research Studentship. We would like to thank Joseph Bonneau for discussions around bribery attacks, Ilya Sergey, Changyu Dong, and Abhiram Kothapalli for comments on early drafts of this paper, and Sergio Lerner and Adrian Eidelman for bringing to our attention that Ethereum’s Byzantium upgrade changed the network’s difficulty calculation.


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Copyright information

© International Financial Cryptography Association 2019

Authors and Affiliations

  • Patrick McCorry
    • 1
  • Alexander Hicks
    • 1
    Email author
  • Sarah Meiklejohn
    • 1
  1. 1.University College LondonLondonUK

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