Winklevoss Index


Winklevoss Blended Bitcoin Index


The collar price for the 4pm ET BTCUSD Gemini auction

What is the Winklevoss Blended Bitcoin Index?

The Winklevoss Blended Bitcoin Index (WBBI)1 is used to collar the 4pm Eastern Time Gemini BTCUSD auction (Gemini Auction). The Gemini Auction is the settlement pricing mechanism used for the Bitcoin Futures Contracts (XBT), which trade on the Cboe Futures Exchange, LLC (CFE) under the ticker symbol “XBT” (contract specifications | fact sheet).

XBT futures are cash-settled contracts based on Gemini’s Auction price for bitcoin, denominated in U.S. dollars (symbol: BTCUSD). XBT futures are specifically designed to allow participants to implement straightforward trading strategies through settlement via a single, tradeable auction price.

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