US500-BTC

Specific details for the US500-BTC perpetual futures contract.

Contract Code	US500-PERP
Underlying Indices	• Equity leg: Composite price for the SPDR S&P 500 ETF (SPY) from primary-listing venues • BTC Price: 3-venue 4-hour V-WAP spot composite of Binance (BTC/USDT); Bybit (BTC/USDT); Coinbase (BTC/USD).
Contract Size	Notional of 10 × SPDR S&P 500 ETF (SPY) point, quoted & settled in BTC
Quote / P&L Currency	BTC
Tick Size	0.01
Trading Hours	24 / 7 continuous order book.
Underlying Cash‑Market Hours	Monday – Friday • Pre‑Market: 04:00 – 09:30 ET • Regular Session: 09:30 – 16:00 ET • After‑Hours: 16:00 – 20:00 ET (NYSE Arca consolidated tape; closed on U.S. market holidays).
Mark-Price Construction	**Mark Price = median(P¹, P², P³), Where: ** Price 1 (P¹) = Index Price × 1+LastFundingRate×(TimeUntilFunding/8) Price 2 (P²) = Index Price plus a rolling 2.5-minute average basis, where the basis is defined as (Bid1 + Ask1)/2 − Index Price. Price 3 (P³) = Last traded price.
Price Formation when the underlying equity market is closed	• Equity leg (SPY): When U.S. equity exchanges are closed, the equity‑leg reference is frozen at the last official SPY print (primary‑listing venues’ closing last price). • BTC leg: The BTC component continues to update in real time using our 3‑venue 4‑hour VWAP composite (Binance BTC/USDT, Bybit BTC/USDT, Coinbase BTC/USD). • Mark Price: mark price is calculated in the same way as during normal trading hours, where each P is computed with the static SPY close and the live BTC composite.
Funding Snapshots	00:00 UTC • 08:00 UTC • 16:00 UTC (every 8 h)
Funding-Rate Formula	Premium Index + Interest Rate; Interest Rate = 0.03% / day (0.01% / 8 h). Caps ± 3 % per 8 h.
Leverage & Margin	Max Leverage 10x; Maintenance margin 25% of Initial Margin.
Liquidation Logic	• Trigger when Equity < MM. • For long positions = Entry Price × (1−Initial Margin Rate + Maintenance Margin Rate) • For short positions = Entry Price × (1 + Initial Margin Rate - Maintenance Margin Rate)
Order Types / TIF	Limit, Market, GTC, GTD, IOC.
Min / Max Order Sizes	Market Max: 0.5 BTC Limit Max: 0.5 BTC