Altcoin perpetual futures open interest surpassed Bitcoin's on Sept. 6 for the first time since December 2024, according to Coinalyze data, highlighting heavier leveraged activity across a broad group of tokens. Bitcoin perpetual open interest stood near $23.9 billion on Sept. 7, or about 37% of positions tracked by the platform, while total Bitcoin open interest was roughly $25 billion including $1.2 billion in dated futures. Zcash was a major contributor to the expansion: ZEC open interest climbed to about $2.4 billion as the token broke above $1,000 and short liquidations exceeded $34 million. Altcoins outside the ten largest crypto assets also rose above $200 billion in market capitalization, gaining more than 10% from the start of September. Rising open interest measures participation and leverage rather than a collective bullish or bearish view, making funding rates, spot volumes and liquidation data important indicators of market stress. Continued growth in spot volume alongside open interest would indicate that derivatives activity retains underlying demand.