Grayscale Bitcoin Trust ETF Changes Index Price for Bitcoin Valuation

Effective April 1, 2026, Grayscale Bitcoin Trust ETF will transition from using the CoinDesk Bitcoin Price Index (XBX) to the CoinDesk Bitcoin Benchmark Rate for valuing its Bitcoin holdings for operational purposes. This change will impact the calculation of the Trust's net asset value (NAV) and NAV per Share. The CoinDesk Bitcoin Benchmark Rate incorporates data from various digital asset trading platforms, selected based on criteria including market quality, security, regulatory compliance, and data provision. The methodology aims to provide a more accurate Bitcoin price by mitigating manipulation and accounting for trading volume and price deviations. In instances where the primary index is unavailable or deemed inaccurate, the Trust will utilize a cascading set of fallback options, including a secondary index from Coin Metrics, pricing from the Trust's principal market, or a good faith estimate by the Sponsor. The Sponsor retains discretion over the index calculation methodology and can change index providers or calculation methods if necessary, with appropriate disclosures to shareholders.