Understanding Perpetual Swaps: The Hottest Trading Instrument in Crypto

Perpetual swaps, or 'perps', are a type of derivative contract that has revolutionized the crypto market. With estimated annual volumes ranging from $40 trillion to $50 trillion, they have become the go-to instrument for professional traders, hedge funds, and retail speculators seeking leveraged exposure to bitcoin and other assets without actually owning them. Despite their widespread use, the inner workings of perps remain poorly understood. To grasp the concept of perps, it's essential to look at their predecessors. In traditional finance, futures contracts provide leveraged exposure to an asset, but they come with an expiration date, after which the contract settles and traders must roll over their positions to maintain exposure. In the early days of crypto, this created persistent issues, including a premium on futures prices compared to spot prices, known as basis, which confused retail traders seeking straightforward exposure. Every time a contract expired, positions were automatically closed, regardless of the trader's intentions. BitMEX, founded by Arthur Hayes and Ben Delo in 2014, attempted to address this by shortening contract durations, but none of these efforts were sufficient. The breakthrough came with the introduction of perpetual swaps, which eliminated the expiry date altogether, creating a derivative contract that tracks the price of an asset indefinitely. This innovation, developed by Delo and launched by BitMEX in 2016, allowed traders to hold positions for any duration without the need for rolling over contracts. However, this created a structural challenge, as the lack of an expiry date meant that nothing would naturally push the contract price back towards the spot price of the underlying asset. To address this, BitMEX introduced a funding rate mechanism, where every eight hours, a payment is exchanged between traders on opposite sides of the market. If the perpetual swap price is above the spot price, long traders pay short traders, and vice versa. This funding rate is calculated based on the deviation of the perpetual swap price from the spot price over the preceding eight-hour window. The further the deviation, the higher the funding rate, creating a self-correcting equilibrium. When the funding rate becomes too high, it becomes expensive for long traders to hold their positions, reducing demand and pushing the price back towards the spot price. Market makers accelerate this process by shorting the perpetual swap and buying spot, capturing the difference as profit. The funding rate mechanism has become the industry standard, used by every major derivatives exchange worldwide. Another defining feature of perpetual swaps is leverage. Most exchanges allow traders to control positions much larger than their deposited capital, with limits varying by platform and jurisdiction. To manage the risks associated with high leverage, perpetual swap platforms use automated liquidation systems, which close positions before they can go negative, protecting the exchange from absorbing the deficit. The speed and reliability of these liquidation engines have become a key competitive differentiator in the market. Today, perpetual swaps are the primary venue for price discovery in crypto, with price movements often originating in perp markets before spreading to spot markets. The structure developed by Delo in 2016 has proven durable enough that regulators in the US are now exploring its application to traditional assets, with the CME potentially listing perpetual swaps on equities. What began as a workaround for the limitations of crypto futures has become one of the most traded financial products globally.