Uniswap is one of the largest decentralized exchanges with a liquidity balance of over 3 billion USD and daily trading volume of over 700 million USD.  It is designed as a system of  smart contracts  on the Ethereum blockchain, and is a new model of liquidity provision, so called automated market making.  We collect and analyze data on all 19 million Uniswap interactions from 2018 to the current time. For this new market, we analyze returns to liquidity provision and returns. We document return chasing in liquidity provision and cross-sectional heterogeneity in returns to liquidity.