HourGlass contributed the following description of Stable Predeposit:

The Hourglass Stable Pre-Deposit Vaults are smart contracts deployed on Ethereum that accept stablecoin deposits (USDT, USDC, frxUSD) before the launch of Stable, a new Layer 1 blockchain. During the pre-deposit phase, users deposit stablecoins at a fixed 1:1 ratio and receive vault shares, with some vaults generating yield through protocols like SparkLend while others implement KYC-segregated treasury management. Once Stable launches, depositors can redeem their shares and bridge the underlying to Stable through the LayerZero integration.

Zellic conducted a security assessment for HourGlass from September 26th to October 3rd, 2025. During this engagement, Zellic reviewed Stable Predeposit's code for security vulnerabilities, design issues, and general weaknesses in security posture.