stETH

Prices stETH fundamentally at 1.0 × ETH/USD, with the Chainlink stETH/ETH market feed retained as a divergence monitor rather than the primary.

stETH is priced fundamentally: stETH/USD = 1.0 × ETH/USD, holding stETH/ETH at parity on Lido's redemption invariant. The Chainlink stETH/ETH market feed is still read, but as a divergence monitor rather than the price source.

• Chain: Ethereum
• Primary — stETHFundamental: 1.0 × ETH/USD, a unit-rate feed. Deployed from eETH_CustomPriceFeed.sol, so the contract name shown on explorers reads eETH — expected, not a mis-deployment.
• Monitor — stETHCrossRate: ETH/USD × stETH/ETH with the Chainlink stETH/ETH market feed. Source stETH_CustomPriceFeed.sol.

---

Why fundamental, with the market feed kept as a monitor

The market CrossRate was the primary until a price-feed audit reversed it.

Pricing stETH off a market feed makes the NAV move with secondary-market noise on an asset whose redemption value is defined by Lido at parity. That is the same reasoning applied to wstETH (stEthPerToken() × ETH/USD) and eETH (1.0 × ETH/USD) — so the fundamental primary makes stETH consistent with its siblings rather than an exception.

Demoting the market feed to a monitor keeps its signal without letting it set the price: a divergence between the fundamental price and the market feed beyond tolerance raises the position's irregular flag, surfacing a depeg rather than silently repricing the book.

---

Base asset

The ETH/USD leg is read from the NAV rather than from a second Chainlink feed held by the contract, so stETH cannot be valued against an ETH price the rest of the NAV disagrees with — it inherits the NAV's own staleness and divergence checks.