The Silent Exodus: SBI's Pool Shutdown and the 60% Hashrate Mirage"

"article": "On July 29, SBI Crypto mined what would be its final block. The following day, the pool's 24-hour average hashrate read 0.452 EH/s — a number so small it barely registers on network dashboards. One month prior, on June 30, SBI was carrying 16.222 EH/s. Between those two dates, roughly 97% of its computing power vanished.\n\nThis was an orderly shutdown. The Stratum service was dismantled in phases. Miners received migration notices. Endpoints went dark one by one. The pool's attributed block share — the percentage of Bitcoin blocks credited to SBI by network observers — fell to 0.72%, roughly 6.8 EH/s of residual hashrate. Then it went to zero. The network kept producing blocks every ten minutes. Difficulty adjusted. The silence between the blocks was total.\n\nThe surface-level interpretation writes itself. Three pools now command more than 60% of Bitcoin's hashrate. Foundry USA at 26.67% of attributed blocks. AntPool at 17.13%. F2Pool at 16.21%. Add them and the sum triggers every decentralization alarm in the ecosystem. Another pool exits; the oligopoly tightens; Satoshi's vision recedes further into the rearview mirror.\n\nRead that narrative too quickly and you miss the actual sequence. The audit trail never lies, but it exposes a different story than the headline. SBI's exit didn't create the concentration; it revealed it. The top three pools had already crossed the 60% line on July 20 — 64.8%, to be precise — and registered 60.8% on July 27. Both readings predate SBI's shutdown. The cause-and-effect story collapses the moment you check the dates.\n\nSBI Crypto was never a protocol-level actor. It was a service provider. A mining pool is an aggregation layer between individual miners and Bitcoin's consensus machinery. It runs Stratum services, connects ASICs to the network, claims block rewards, deducts a fee — typically 1% to 4% — and distributes payouts. There is no novel architecture here. No new consensus mechanism. No protocol upgrade. Just a business running servers in one of the most competitive commoditized markets in digital finance.\n\nThe parent company, SBI Group, is one of Japan's largest financial conglomerates. Its entry into mining was always an institutional sideline — a hedge, a relationship-building exercise, a seat at the table. Mining was never SBI's religion. It was a line item. And the line item stopped making sense.\n\nThe April 2024 halving cut the block subsidy from 6.25 BTC to 3.125 BTC. For identical hashrate, revenue halved overnight. Hashprice — the market value of one terahash per second per day — fell in step. Japan's industrial electricity prices rank among the highest in the developed world. A Japanese pool paying those rates, collecting 1% to 4% on halved rewards, faced a math problem that no amount of loyalty could solve.\n\nThe broader environment was no kinder. Bitcoin mining has matured into a capital-intensive industry dominated by institutional players with access to cheap power, stranded energy, and public market financing.