[River: 81% of Bitcoin supply has remained unmoved for at least 6 months, retail investors shift from selling to buying] According to a report by Crypto Briefing on September 26, River Financial's newsletter published on September 23 revealed that more than four-fifths of Bitcoin has not moved for at least six months, meaning approximately 81% of the supply is in a 'dormant' state. Data shows that long-term holders have accumulated over 3 million BTC since 2020, while the movement of older coins has nearly stagnated, with only about 300,000 BTC held long-term changing hands in the first half of 2026. Notably, there has been a shift in retail investor behavior: individual and retail investors, who had net sold 140,000 BTC in the first half of 2026, reversed course in the third quarter by net purchasing over 107,000 BTC. Among them, 'dolphin' wallets holding between 100 and 1,000 BTC have bought over 113,000 BTC since mid-July. In terms of market context, Bitcoin's price has risen approximately 50% from its June 2026 low, though trading volume for the year has declined by 30%, and ETF inflows remain below average. Based on the report's calculations, Bitcoin's circulating supply is approximately 19.7 million BTC, and if 81% remains unmoved, the actual active circulating supply is only around 3.7 million BTC.