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Pow.re's Ian Descoteaux on Proxy Pools and Cobo Custody
Three lines of evidence that large Bitcoin mining pools share custody, block templates and accelerated transactions, and a free auditing service to track them.
Forty-three thousand seven hundred bitcoin. That is how much Ian Descoteaux said had flowed into one small set of addresses from mining pool payouts in the first half of 2024 alone. Descoteaux is co-founder and chief technology officer of Pow.re, and he made the case at Mining Disrupt Miami 2024, held June 24 to 26, 2024. In his words: "That represents 36% of all the non-exchange pool payouts." His argument was that a group of large pools were acting less like competitors and more like one operation.
Proxy mining, where a smaller pool relies on a bigger one for block templates or custody, is fine when it is done in the open, he said. EMCD's blocks, for example, are marked as built by AntPool. The problem is when it is hidden. He offered three lines of evidence.
First, custody. Payouts from AntPool, BTC.com, EMCD, Binance Pool and others landed in the same addresses, which on-chain analysis ties to Cobo, a custody company started by the founders of F2Pool. Pow.re even traced its own payment for an S21 from Bitmain to one of those addresses within two hops. Second, the Merkle branches pools hand to their miners.
Two independent pools should almost never produce matching branches. In his charts, about half of them did. Third, accelerated transactions. The transaction a pool gives its miners next to the coinbase should be the best-paying one in the block.
He showed several pools all working on the same transaction paying 9.03 sats per vbyte, about ten times below the network average at the time, which points to a shared paid acceleration service. Then the numbers. In his best case, AntPool and the pools around it held 37.2% of the network, with Foundry at 29.1% and ViaBTC at 13.9%. In his likely case, counting every pool he believed Cobo held in custody, the group reached 50.3%.
He called that quite concerning. Switching pools, or moving to Stratum V2, does not solve it in his view, because it only moves the problem to other miners. His answer was a live audit. Pow.re had logged pool data for three months and was building a free service to score pools, verify payouts every day, and warn miners when their pool starts acting as a proxy, with an API due before Q4 2024.
"Of course, it's going to be given for free to the mining community," he said. When he spoke, Bitcoin traded at $61,272. On October 16, 2026, it was at $82,531. The full story, with the evidence he presented, is on miningdisrupt.com, and more stories like it play around the clock on Bitcoin Radio.