Perpetual Futures Glossary

Quick definitions of the terms you'll meet when trading perpetual futures - and what each one means for your positions on BULK.

Perpetual future (perp)

A derivative contract that tracks an asset’s price with no expiry date; traders can hold long or short positions indefinitely while paying or receiving periodic funding.

Spot market

The market where the actual asset is bought and sold immediately. Perpetual prices are anchored to a spot index via funding.

Funding rate

A periodic payment between longs and shorts that keeps a perpetual near its underlying index; positive funding means longs pay shorts, negative means shorts pay longs.

Open interest (OI)

The total number of outstanding perpetual contracts that haven’t been closed — a measure of how much leveraged positioning is at risk.

Leverage

Using borrowed margin to control a position larger than your collateral, amplifying both gains and losses.

Margin

The collateral required to open and maintain a leveraged position.

Isolated margin

A margin mode where a position’s risk is capped at the margin allocated to it alone, separate from the rest of the account.

Portfolio margin

A margin mode where positions are risked and margined together so that hedged positions offset each other’s margin requirements.

Mark price

The price used to value positions for margin and liquidation purposes, derived from the index rather than the last traded print.

Index price

A reference price for the underlying asset, typically aggregated from spot venues, used to settle funding and mark positions.

Liquidation

Forced closure of a position when its margin falls below the maintenance requirement.

Liquidation cascade

A chain of forced liquidations that push price against the next weakest leveraged position, often producing sharp, fast moves.

Auto-deleveraging (ADL)

A last-resort mechanism where profitable traders on the opposite side absorb the shortfall of a bankrupt position.

Long

A position that profits when the asset’s price rises.

Short

A position that profits when the asset’s price falls.

Order book

The list of resting buy and sell limit orders for a market, showing available liquidity at each price level.

Best bid and offer (BBO)

The highest bid and lowest ask currently available in the order book — the best price a market order can fill against.

Taker

A trader who submits a marketable order that fills immediately against resting liquidity, paying a fee.

Maker

A trader who posts a resting limit order that provides liquidity to the book, often receiving a rebate or lower fee.

Spread

The difference between the best bid and best ask; a measure of market tightness and liquidity.

Slippage

The difference between the expected price of a trade and the price actually filled, caused by insufficient liquidity.

Volatility

The magnitude and speed of price fluctuations; a core input for sizing positions and setting stops on perps.

Basis

The difference between the perpetual price and the underlying spot index, which drives the funding rate.

Access code

A one-time code used to enter BULK while the platform is invite-only; codes also attach the issuing referral link to the new account.

Referral code

A code (such as YETI) that attributes a new account to the referrer’s link when the account is created through it.