The platform enforces position limits in two aspects: the absolute position size (meaning it cannot exceed a specified notional value) and the relative position size (meaning its proportion of the platform's open interest (OI) must not surpass a defined threshold). When the OI limit is triggered, only order cancellations and reduce-only operations are permitted.
For a single user ID, main and sub-accounts are calculated separately. An open interest (OI) risk control limit will be triggered if the total position size exceeds the maximum of: the notional value threshold of futures positions for the single user ID; or the platform's OI × 0.5 × futures position ratio threshold for the single user ID. Since the platform OI is calculated bilaterally (long + short), but the OI limit is applied unilaterally, a 0.5 multiplier is applied accordingly.
For a single user, main and sub-accounts are calculated in aggregate. An open interest (OI) risk control limit will be triggered if the total position size exceeds the maximum of: the notional value threshold for futures positions across main and sub-accounts; or the platform's OI × 0.5 × futures position ratio threshold for main and sub-accounts. In such cases, both the main and sub-accounts will trigger the OI risk control limit.
Note: The total position size is calculated separately for long and short positions. It includes both current positions and open orders.
Example:
Under a single user ID, the account holds a long position of 10,000 USDT, with a long order of 6,000 USDT and a short order of 3,000 USDT. The notional value threshold of futures positions for the single user ID is 15,000 USDT, and the futures position ratio threshold for the single user ID is 10%. The platform's OI size is 200,000 USDT. Therefore, the long position size for this user ID is 10,000 USDT + 6,000 USDT = 16,000 USDT, which is greater than maximum (15,000 USDT, 200,000 USDT × 0.5 × 10%). The long position triggers the OI risk control limit.
Under a single user, the main account holds a long position of 18,000 USDT, and there is one sub-account with a long position of 15,000 USDT. The notional value threshold for futures positions across the main and sub-accounts is 30,000 USDT, and the futures position ratio threshold for the main and sub-accounts is 20%. The platform's OI size (long + short) is 200,000 USDT. Therefore, the long position size for this user is 18,000 USDT + 15,000 USDT = 33,000 USDT, which is greater than maximum (30,000 USDT, 200,000 USDT × 0.5 × 20%). The user's position triggers the OI risk control limit.