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General TradingF
Front-Running
Front-running is the unethical or illegal practice of executing trades based on advance knowledge of pending orders from other market participants. In traditional finance, a broker may trade ahead of a large client order, while in DeFi, bots detect pending transactions in the mempool and place their own trades first to profit.
Example
“A MEV bot detected a large pending swap on Uniswap in the Ethereum mempool and front-ran it by placing its own buy order first, then selling at a higher price after the large order pushed the price up.”