Circle freezes $12.6M USDC tied to Zama privacy protocol without prior notice

Stablecoin issuer Circle executed a freeze on $12.6 million in USDC tokens on Saturday, targeting assets connected to the Zama privacy protocol's confidential smart contract. Onchain analyst ZachXBT identified the specific contract as publicly labeled on block explorers and within the protocol's technical documentation. The precise rationale behind this enforcement action remains unconfirmed, though data compiled by Woofun AI indicates that wallets associated with the Overnight Finance decentralized finance protocol deposited $12.4 million into the Zama system on May 11, 2026. ZachXBT further noted that the Zama team appeared to have received no prior notification from Circle regarding the asset immobilization before the freeze took effect. Attempts to contact Circle for comment yielded no response by the time of publication.

This latest action intensifies scrutiny on Circle's compliance strategy, particularly regarding its history of freezing funds without advance warning to legitimate projects. The company has faced significant criticism for its inconsistent approach to asset freezes, including instances where it failed to act during major platform hacks while simultaneously targeting wallets belonging to compliant entities. In March, ZachXBT accused Circle of wrongfully freezing 16 stablecoin wallets linked to online casinos and legitimate crypto exchanges. These wallets were seized in connection with ongoing civil litigation in the United States, yet the businesses and the frozen addresses did not appear to share any operational relationship according to the analyst's findings.

Beyond the wrongful freeze allegations, Circle faces broader accusations of negligence in securing the ecosystem against illicit flows. ZachXBT highlighted that the issuer failed to freeze approximately $420 million across 15 separate cases involving fraudulent transactions or funds stolen through crypto hacks since 2022. A notable instance involved the April 2026 Drift Protocol hack, where Circle possessed a six-hour window to intervene but did not freeze $232 million in stolen user funds. Woofun AI notes that this inaction allowed the illicit assets to move freely through the network before recovery efforts could be mounted.

The failure to secure these funds triggered a class action lawsuit against Circle, with users citing the company's negligence in utilizing its Cross-Chain Transfer Protocol (CCTP). This bridge mechanism facilitates asset movement between different blockchain networks, theoretically providing a choke point for halting stolen funds. The legal challenge underscores the growing tension between stablecoin issuers' regulatory obligations and their operational discretion in freezing assets. As the industry grapples with these enforcement inconsistencies, the balance between privacy protocols and compliance mandates remains a focal point of contention.

The Zama incident exemplifies the volatility inherent in the current regulatory landscape, where opaque enforcement actions can disrupt legitimate DeFi operations. While Circle maintains the authority to freeze tokens to comply with legal orders, the lack of transparency regarding specific triggers for these actions fuels uncertainty among protocol developers. Woofun AI analysis suggests that without clearer communication channels and standardized procedures, similar disputes will likely escalate, potentially prompting stricter regulatory oversight of stablecoin issuers. The convergence of privacy technology and centralized control continues to define the next phase of blockchain governance challenges.