What Assay is

Several issuers wrap the same share on Solana. xStocks issues AAPLx and Ondo issues AAPLon; both stand for Apple stock. Every product that holds them assumes the wrapper is worth the stock, and nothing prices the case where it is not, for example when an issuer stops redeeming or pauses its token.

Assay measures that difference from Pyth data while the stock market is open. It runs a market in cover that pays when the difference holds.

#The three parts

The assay. For each wrapper, Assay computes

from signed Pyth prices. d is the gap between what the token trades at and what it redeems for. A negative d means the token trades below its redemption value. See The assay.

Cover pools. Each wrapper has one pool per week. Underwriters deposit USDC; buyers pay a premium up front for a notional amount of cover. The premium rate rises with how much of the pool is used. See Pools and premiums.

The trigger. A pool pays when d stays at or below −2% for 30 minutes of the stock’s regular trading session. That is proven on chain by observations: signed Pyth updates that anyone can post. See The trigger.

#Who it is for

• Holders of stock tokens, and protocols that accept them as collateral, who want to be paid if a wrapper stops tracking its share.
• Underwriters who want to earn premiums for carrying that risk, issuer by issuer.
• Anyone who wants to see the gap. The assay board shows every wrapper against its stock, with the confidence band, during market hours.

#What it covers

Both are measured against the same Pyth price of AAPL, so the two issuers can be compared directly.

No real depeg of AAPLx or AAPLon has happened. Pools marked TEST exist to show a trigger with real data; see TEST pools.