Crypto rules finalized, Bitcoin retreats, Solana upgrades | Weekly recap

In this week’s edition of the weekly recap, US regulators finalized stablecoin rules under the GENIUS Act, Bitcoin lost ground after a sharp reversal in ETF flows, and Solana activated Alpenglow. Corporate Bitcoin financing, institutional custody deals, and Ethereum’s postponed testnet upgrade also shaped crypto.news coverage for Oct. 18–24. Summary Jan. 18, 2027, is the effective date for the OCC’s final GENIUS Act stablecoin rules. $635.49 million left US spot Bitcoin ETFs on Oct. 22, ending three consecutive inflow sessions. Solana activated Alpenglow on Oct. 21, targeting roughly 150-millisecond finality with its new consensus system. Strategy increased its Bitcoin holdings to 848,517 BTC and expanded its securities buyback authorization. Strive closed a $630 million preferred stock offering carrying a fixed 15% annual dividend rate. GENIUS Act rules set January start date The Office of the Comptroller of the Currency finalized stablecoin regulations on Oct. 21, establishing standards for reserve assets, redemptions, risk management, custody and issuer supervision. The rules take effect Jan. 18, 2027, and cover issuers and related activities under the agency’s jurisdiction. Exi...