Upcoming Change Notice: Derivatives Open Interest Standardizing to Single-Sided Reporting

Effective November 10, 2026, all derivatives open interest will be standardized to single-sided reporting, where each contract is counted once. Exchanges report open interest differently, which makes their numbers hard to compare, and this change puts every exchange on the same basis.

• Exchanges that previously reported double-sided open interest will show a one-time drop of roughly 50%. This reflects the methodology change, not a drop in trading activity.
• Affected endpoints and fields:
  • /derivatives: open_interest for each ticker
  • /derivatives/exchanges: open_interest_btc for each exchange. Results sorted by open_interest_btc_desc (default) or open_interest_btc_asc may change order.
  • /derivatives/exchanges/{id}: open_interest_btc, plus tickers.open_interest_usd when include_tickers is used
• The response structure stays the same and only the values change. There is no parameter or legacy field to retrieve double-sided open interest.

Action needed: If your application uses derivatives open interest, review any logic that compares values over time, alerts or thresholds based on open interest levels, and stored historical data you combine with new API responses.

More details: full announcement