By the time SBI Crypto pulled the plug on its Bitcoin pool in Japan on July 31, its seven-day average hashrate had fallen 64% in a month. Later that day, a Hashrate Index reading put Foundry USA, AntPool and F2Pool at 60% of recent blocks. The timing makes them look connected. Weekly data tell a messier story.

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Mar 25, 2026 · Gino Matos

SBI Crypto’s official update set the first cutoff at 22:00 UTC on July 30, or 07:00 JST on July 31. Share acceptance stopped, and miners began a graceful disconnect….