apxUSD is a stablecoin protocol created by Apyx that is backed by off-chain preferred shares that generate dividend yields. The protocol issues apxUSD (a 1:1 backed stablecoin) and apyUSD (a yield-bearing ERC-4626 vault wrapper). Minting is performed through EIP-712 signed orders with built-in delays, enabling off-chain compliance checks before execution. Yield from preferred share dividends is distributed through a vesting mechanism that gradually releases value to apyUSD depositors over configurable periods.

During this manual code review, Certora identified 11 issues including one of high severity which has been fixed and confirmed.