Bitcoin used to own the crypto derivatives market — 90%+ of total open interest. That era's over.

Across 30 major exchanges, altcoins now hold 57.4% of total open interest vs. $BTC's 42.6%. That's a 14.8pp flip.

This isn't just a rotation — it's a structural change in how leverage is distributed. Volatility, liquidity depth, and liquidation cascades now live in altcoin books as much as Bitcoin's. You can't read the derivatives market through $BTC alone anymore.

The implication: tail risk and gamma exposure are fragmented across dozens of tokens. That makes the system more complex, more prone to isolated blow-ups, and harder to hedge at the index level. Bitcoin's still the anchor, but the leverage map has fundamentally changed.