ING’s blockchain team is testing a privacy technology called “bulletproofs,” the latest in a series of seemingly unlikely cypherpunk experiments at the Netherlands-based global bank. Developed and refined by hardcore cryptographers at Stanford University, University College London and startup Blockstream, bulletproofs are designed to hide the amounts being transferred in bitcoin transactions, which are normally visible to anyone. But banks have privacy concerns about blockchains too, since they don’t want to expose competitive or sensitive client data to rivals. One early solution was zero-knowledge proofs (ZKPs), a ... (full story)