Bitcoin's estimated US mining footprint shrank as Russia's grew, with little change in top-three country concentration.

Hashrate Index's Oct. 5 country estimates put the US at about 335 EH/s, down from 345 EH/s in the previous edition, while Russia rose from 162 to 170 EH/s.

The US, Russia and China still account for roughly 66% of the estimated network. Their combined share slipped by about 0.8%, even as the global hashrate estimate stayed almost flat.

That is a modest change in geographic concentration, with a clearer shift in the balance between the two largest mining locations.

Luxor Technology's mining data platform Hashrate Index labels the report its fourth-quarter update, but the figures describe observations from the preceding third quarter. Its July 16 comparison edition described June estimates.

The October publication is neither a completed fourth-quarter result nor a live census of where machines are operating on Oct. 6.

The comparison separates absolute mining activity from network share. Estimated US hashrate declined as its share fell from 36.7% to 35.6%, while Russia gained both estimated hashrate and share, rising from 17.2% to 18.1%. China's estimate declined from about 115 to 110 EH/s.

The network total is a 30-day simple moving average of hashrate, the computing work devoted to mining.

From an on-chain analytics and liquidity distribution perspective, developments around "3 countries control 66% of Bitcoin mining, but 1 rival is gaining" signal important shifts in network participation. Market participants observe that derivative funding metrics, exchange reserve telemetry, and smart contract protocol interactions reflect cautious accumulation alongside disciplined risk hedging across the sector.

Technical research analysts at CryptoAce VIP note that high-density order book clusters and volume-weighted average price (VWAP) benchmarks near recent consolidation floors will serve as pivotal indicators. Market observers are advised to cross-examine telemetry on verified block explorers before making capital allocations.

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