ZachXBT dossier alleges Circle failed to freeze over $420M in USDC across multiple hacks

ZachXBT published a dossier claiming Circle delayed or failed to freeze USDC linked to multiple exploits since 2022, identifying roughly $420M–$440M in alleged lapses. He specifically highlighted the Drift protocol exploit — reported at about $280M in losses with roughly $232M bridged USDC — and said attacker funds moved across Circle’s bridge for hours without a freeze ^{[1] [2] [3]}.

Coverage of the allegations varies by outlet: AmbCrypto and Blockonomi summarized the $420M figure and a list of about 15 cases, while CryptoBriefing reported the total could exceed $440M, reflecting different tallies and case counts in ZachXBT’s on-chain analysis ^{[4] [1] [5]}.

Critics have faulted Circle’s apparent inaction in some incidents, though reporting notes legal and operational constraints — Coindesk emphasized that freezing assets without clear legal authorization carries risks, a factor central to debate over issuer intervention — and outlets say the allegations raise questions about enforcement of stablecoin controls and trust in USDC ^{[6] [2]}.

The 'Circle Files' have prompted renewed scrutiny of how stablecoin issuers respond to hacks; the claims derive from on-chain sleuthing and media reporting, and further investigation and comment from Circle and regulators will determine any operational or legal implications ^{[1] [6] [5]}.