CoW Swap order guarantees formally verified by Verity Lab

CoW Swap announced that its core order guarantees — limit prices hold and orders don't overfill — have been formally verified by Verity (@Veritylab), the Lean 4-based formal verification project from LFG Labs. Unlike audit-style review, Verity produces machine-checked mathematical proofs of smart contract behavior, closing the gap between what CoW claims about its order execution and what can be proven.

• Formal proofs cover the settle path of the GPv2Settlement contract
• Verifies that trades never breach a user's limit price or overfill an order
• Verification work appears in the LFG Labs ethereum-verification-benchmark repo

CoW Swap framed the result as independent expert confirmation of properties it has long advertised to traders — a step toward provable execution guarantees for its batch-auction settlement.