What "inverse" means
Every perpetual you have traded so far on Arbitron was most likely linear: a BTC-USDT contract margined and settled in USDT — stablecoin in, stablecoin out. Inverse perpetuals flip that around. A BTC-USD inverse contract is margined and settled in BTC itself: your collateral is the coin, and your profit or loss arrives in the coin.
Inverse contracts also size differently. Instead of a coin quantity, each contract carries a fixed USD face value — on most venues 1 BTC contract = $100, 1 ETH contract = $10. You trade a whole number of contracts, and a $10,000 position is simply 100 BTC contracts regardless of where the price is. Arbitron keeps the familiar UX: you still enter order size in USD, and the conversion to contracts happens per venue automatically.
PnL accrues in the base coin and is shown converted to USD at the mark price. The symbol format gives the market away at a glance: BASE-USDT is linear, BASE-USD is inverse.
Why inverse matters for arbitrage
The inverse market is a genuinely separate venue: its own order books, its own participants (miners and long-term holders margining in coin), its own funding rates. Prices track the same underlying but dislocate independently from the linear twin — which means a whole additional universe of cross-exchange spreads, often less crowded than the linear one.
One structural rule: inverse trades against inverse. A trading card pairs BASE-USD with BASE-USD — never an inverse leg against a linear leg. The two contract types have different convexity (their PnL curves bend differently as price moves), so a mixed pair would not be delta-neutral even at equal notional. Arbitron enforces this in the card constructor.
Inverse in the scanner
The scanner has a dedicated Inverse tab: same columns, same backtest, same filters as the Arbitrage tab, but running on BASE-USD instruments across the venues that list them. Volume figures are real 24h coin-margined turnover fetched per exchange, and the spread history chart works for inverse rows just like linear ones.
Funding on inverse perps uses the same mechanism you know from linear — periodic payments between longs and shorts, intervals varying by venue and symbol — except payments are made in the base coin. The scanner displays inverse funding alongside linear without special treatment.
Inverse trading cards
The New Card dialog has a market type toggle: Linear or Inverse. Choosing Inverse narrows both exchange pickers to the venues with coin-margined markets — currently 13: Binance, Bybit, OKX, Bitget, Gate.io, MEXC, KuCoin, HTX, BingX, Phemex, BloFin, BitMart and CoinEx. Pasting a BASE-USD symbol selects the toggle automatically.
Because contracts are coin-margined, both exchange accounts need base-coin collateral — actual BTC for a BTC-USD card, not USDT. This is also why integration favors BTC and ETH: they are the only inverse markets every venue lists with meaningful depth.
One-leg mode is not available for inverse cards — inverse trading is classic two-leg only. Everything else about card mechanics (thresholds, states, protective limits) matches linear cards.
Risks specific to inverse
Collateral volatility. Your margin is the coin, so the USD value of your account moves with the market even while the position itself is delta-neutral. A 20% BTC drawdown shrinks your margin cushion by 20% in USD terms without a single losing trade.
Convexity. Inverse PnL is non-linear: as price falls, each dollar of adverse move costs a short more coin than the previous one. Liquidation arrives on a different curve than linear traders are used to — run the numbers in the liquidation calculator and keep leverage lower than you would on linear.
Liquidity. Outside BTC and ETH on the top venues, inverse books are thinner than their linear twins. Check depth at your size before trading and size down relative to your linear habits.