According to Foresight News, CoW DAO tweeted that "the CoW Protocol team has noticed an example of surplus shifting that negatively impacted traders on CoW Swap while (albeit unfairly) benefiting CoW AMM liquidity providers (LPs). CoW Protocol takes an unfavorable view of surplus shifting, believing that such practices may not maximize user fairness. Surplus shifting is a known but rare issue, and when such situations occur, we will actively penthe solver and compensate users. Once the investigation is complete, CoW DAO will take appropriate measures to address this issue."

< p related transaction was a CoW Protocol batch where a solver used liquidity from the CoW AMM pool as part of its solution. In this case, the right to execute the batch was won by a solver who provided CoW Swap traders with a worse price than expected, while providing more surplus to the CoW AMM pool and winning the right to execute the batch in the solver competition.