Steakhouse Confidential Prime USDC

Zama’s first design began from a specific leak: a normal ERC-4626 deposit reveals the wallet, amount and time. Its answer was not a new private lending market. Users shield USDC into cUSDC, then place encrypted amounts in a shared batch. Only the batch total is decrypted for the public vault transaction.

That boundary is intentional. Observers can still see who joined a batch and the aggregate amount. With only one independent depositor, the total can reveal that person’s amount; an attacker controlling the other participants may subtract known deposits. Zama therefore describes meaningful privacy against passive observation, not perfect anonymity or a mixer.

On 19 June, Steakhouse’s deployer created 0xbEEF…542B through Morpho’s Vault V2 factory. Its immutable asset is Circle’s ordinary Ethereum USDC. The token named steakcUSDC is the vault receipt: its exchange rate follows total recoverable USDC divided by shares. It is not USDC principal sitting unchanged in a holder’s wallet.

Zama placed another layer over that receipt. Registry address 0x66Bf…C458 is csteakcUSDC, the confidential wrapper of steakcUSDC; cUSDC at 0xe978…72B2 similarly wraps USDC. The deposit batcher receives encrypted cUSDC, deposits the decrypted aggregate, wraps the returned public shares and distributes encrypted claims. Withdrawal runs the mirror image.

Deposits opened on 23 June. Zama described roughly 24-hour batches: users may quit before dispatch; after dispatch, a callback either settles the aggregate route or cancels it and returns wrapped inputs if the vault call fails or a deadline passes. Privacy improves with a larger pool, while waiting for the pool slows settlement.

A 12-week incentive began the next day, declining through three phases and scheduled to end on 15 September. The bonus was added to the vault for current participants. It was a launch program, separate from the lending strategy’s changing native return.

On 5 September, the vault accounted for about 39.420 million USDC. About 94.10% of the adapter position sat in a USDC market backed by cbBTC; wstETH represented about 4.98% and WETH about 0.92%. Each market used an 86% liquidation loan-to-value setting. Launch material had also named WBTC, but no WBTC position appeared in this snapshot.

The vault supplies USDC; it does not make a bilateral loan to a named institution. Borrowers enter Morpho markets and post crypto collateral. Interest raises vault assets. If liquidation proceeds fail to cover debt, the realized shortfall travels the other way through the adapter and lowers share value. “Blue-chip collateral” does not create a Steakhouse repayment obligation.

The same snapshot showed about 33.439 million USDC withdrawable, while only about 1,762 USDC sat idle. A normal redemption uses idle funds first and then pulls from the liquidity adapter. If that route cannot obtain the requested USDC, the public call cannot settle in full; a confidential batch can cancel and recover its inputs. Vault V2 also offers a more technical force-deallocation route, with gas costs and a configured penalty, when its conditions are met.

For confidential users, redemption also crosses the withdrawal batcher: encrypted csteakcUSDC goes in, the aggregate public shares are redeemed, and cUSDC returns. A visible share price near 1.018632 USDC was accounting history at that block, not a promise of par or immediate cash.

At the reviewed snapshot, the Steakhouse VaultV2Supervisor contract was the on-chain owner. A Safe requiring signatures from two of its seven registered owner addresses served as curator, setting strategy limits, and three allocator addresses could move funds within approved adapters and caps. These address counts do not establish a number of people. Cap increases, adapter changes and changes to the deposit-side access filter carried seven-day vault delays. The functions changing allocators and fees had zero configured delay. Owner actions also pass through the separate Supervisor, whose documented delay is 14 days.

Management and performance fees were zero at review, yet zero is a mutable setting. The only live gate restricted which accounts could fund deposits or mints; share-transfer gates were unset. Encryption hides individual amounts. It does not hide who can configure the public machine, which markets hold the USDC, or how much liquidity an exit can reach.

Steakhouse’s vault terms identify Carniceria Tropical Inc. as the interface operator and curator, while disclaiming custody and fiduciary status and warning of partial or total loss. That stated legal capacity is distinct from the on-chain owner contract and registered role addresses; it does not make the company a Morpho borrower or a guarantor of principal or repayment.