Open any stock perp and you will find two prices side by side. One is the mark, the price the perp itself is trading at. The other is the oracle, the reference the perp is built to follow. They are usually close. They are never the same thing, and on a stock the difference between them behaves in a way a crypto trader will not expect.
The oracle is the reference
The oracle price stands for the thing the contract tracks. On an NVDA perp that is the share. On an S&P 500 perp it is the index. Nobody trades at the oracle. It is an input, brought in from outside the book so the contract has something to be measured against. The crypto version of the same job is described in the index price behind a perpetual.
The mark is the perp’s own price
The mark is where the perp trades on its own book. It is set by the orders resting there and the traders hitting them. Venues value open positions against a mark so that profit, loss and margin follow the contract’s own market, which is the reasoning laid out in mark price versus last price. When you ask what a position is worth right now, the mark is the answer.
Why they drift apart
Nothing forces perp traders to agree with the reference. If buyers are more urgent than sellers, the mark sits above the oracle. If sellers are, it sits below. Funding then charges the heavier side, which pulls the two back together over time.
On a crypto perp the reference is a spot market that never shuts. A stock is different. The share stops trading in the evening and all weekend, while the perp carries on. In those hours the mark is the only price that is still being made, and it can say things the reference has no way to say.
Which one to read
Read the mark to know where the contract is and what a position is worth. Read the oracle to know what the contract is tied to. Read the gap between them, the premium, to see which side is leaning, which is the subject of reading the premium on a stock perp.
For the move since the stock market closed, neither price alone is enough. NoVo measures the perp now against the perp’s own price at the last cash close. Measuring the contract against itself cancels any standing gap to the reference, so what is left is the move.
Where it breaks
A mark is only as good as the book behind it. In thin hours a single order can move it. An oracle is only as good as its source, and that source is chosen by the team that listed the market. The same ticker can also list on more than one book, each with its own mark. None of those marks is the price of the stock. Each is the price of one contract on one book.
Where to see both
The Stocks On-Chain tab of the Crypto Market Map lists every stock and index perp with its mark and its premium to the oracle. Dr. NoVo, the Financial Markets Super Intelligence, reads both and names which one a figure came from.