Winklevoss Index


Winklevoss Blended BTC Index


The collar price for the
4pm ET BTCUSD Gemini auction


Winklevoss Blended ETH Index


The collar price for the
4pm ET ETHUSD Gemini auction

What are the Winklevoss Blended Indices?

The Winklevoss Blended Indices (WBxI)1 are used to collar their respective 4pm Eastern Time Gemini auctions. The WBxl includes the Winklevoss Blended Bitcoin Index (WBBI) and the Winklevoss Blended Ethereum Index (WBEI).

The BTCUSD Gemini Auction is the settlement pricing mechanism used for the Cboe Bitcoin (USD) 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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