63 Pages Posted: 23 Oct 2018 Last revised: 13 Jul 2020

Date Written: July 10, 2020

Abstract

Pump-and-dump schemes (P&Ds) are pervasive in the cryptocurrency market. We find that P&Ds lead to short-term bubbles featuring dramatic increases in prices, volume, and volatility. Prices peak within minutes and quick reversals follow. The evidence we document, including price run-ups before P&Ds start, implies significant wealth transfers between insiders and outsiders. Bittrex, a cryptocurrency exchange, banned P&Ds on November 24, 2017. Using a difference-in-differences approach, we provide causal evidence that P&Ds are detrimental to the liquidity and price of cryptocurrencies. We discuss potential mechanisms why outsiders are willing to participate and describe how our findings shed light on manipulation theories.