Ⅲ. Price limit rules

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OKX

Price limit is one of the important risk control methods to protect investors and prevent the market from being manipulated. If there is no price limit, a few traders can make the contract price fluctuate greatly and create a large apportionment, by using a small amount of funds and a high leverage level. On the other hand, if the price limit rules are simple, it will lead to a lack of vitality in the market, and there will be no premium with the spot, and the contract trading will be meaningless.

In order to have a better risk control, the full rules of price limit are not completely disclosed. OKX will dynamically set risk control rules, based on more than a dozen parameters such as market trading volume, turnover, open interest, and the percentage of index deviation.

A. Contract price limit rules

Phase Highest price limit Lowest price limit
Within 10 mins of contract generation Index * (1 + X) Index * (1 - X)
10 mins after contract generation Min[Max(Index, Index ( 1 + Y) + Avg. premium in last 5 mins), Index * (1 + Z)] Max[Min(Index, Index * (1 - Y) + Avg. premium in last 5 mins), Index * (1 - Z)]
For the details of X, Y, Z parameters, please visit: https://www.okx.com/trade-market/info/swap

Z equals 3% in 30 mins before weekly futures delivered

The above parameters and indicators may be adjusted according to market conditions, and the adjustment will not be notified separately.

Remarks

Index: USDT-margined, USDC-margined and crypto-margined contracts refer to the index price of base currency as their index price.

E.g. BTCUSDT perpetual contract refers to the BTC/USDT index price, BTCUSDC perpetual contract refers to the BTC/USDC index price, BTCUSD perpetual contract refers to the BTC/USD index price.

Average premium in the past 5 minutes is calculated as follows:

Record the 1-minute candlestick data of the contract and spot index in the past 5 minutes, calculate "(opening price + closing price) / 2" per minute, calculate the difference between the contract and index, and take an average of all differences in the past 5 minutes.

The above rules apply to all contracts (including USDT, USDC and crypto-margined contracts). And there are also restrictions on opening and closing positions: when open a long position or close a short position, the order price is higher than the highest price; when open a short position or close a long position, the order price is lower than the lowest price, the limit price will be triggered.

B. Margin price limit

The highest price of buy order and lowest price of sell order are calculated as follows:
Highest price of buy order = 1.05 * Mark price
Lowest price of sell order = 0.95 * Mark price

C. Options price limit

OKX will dynamically set risk control rules based on options market price, Delta and other parameters. In order to make users better understand price limit, and convenient for users to trade, the highest price of buy order and lowest price of sell order are calculated as follows:

Highest price of buy order = Mark price of options + Adjustment coefficient * Max (0.004, 0.016 * abs (Delta));

Lowest price of sell order = Mark price of options - Adjustment coefficient * Max (0.004, 0.016 * abs (Delta));

OKX may adjust the above parameters according to certain market conditions, and the adjustment coefficients of different crypto options contracts are different. The limit price also needs to follow the smallest price unit requirement. Orders placed and forced reduction orders from common users also follow the price limit rules.