COINBASE’S BLOG SAID IT HOLDS 5% OF ALL BITCOIN — THE SAME PAGE NOW SAYS 12%, WITH NO EDIT NOTE — ITS 10-Q COUNTS 3.0 MILLION CUSTOMER COINS, NEARLY 15%

Coinbase filed its third-quarter 10-Q on October 29, 2026. It counts 3.0 million bitcoin held for customers at September 30. The filing defines that count as coins “held or managed on behalf of customers in digital wallets on our platform, including our custody services but excluding assets for which the customer holds full or partial keys.” So these are coins where the customer holds no key at all. Block 969,369 was the last block of September 30, UTC, and 20,091,781 bitcoin had been issued by then. 3.0 million of those is nearly 15%.

On October 13, Coinbase posted a blog on getting bitcoin ready for quantum computers. When we read it on October 14, it said Coinbase “holds ~5% of all BTC in existence.” Bitbo reported the same 5% that day. On October 30 the same page says Coinbase “holds ~12% of all BTC in existence.” It still carries the October 13 date, and there’s no note saying it changed. Our October 14 story quoted the 5% as Coinbase’s own figure, one we hadn’t checked.

Twelve percent of the coins issued is about 2.41 million. The filing’s count is about 590,000 more than that. The blog doesn’t say what its number covers. The filing does, and its number is the biggest of the three.

Anyone can check how many bitcoin exist. Every node adds it up from the blocks. Nobody outside can check how many a custodian holds. You get the number it prints, and between October 14 and October 30 Coinbase printed two for the same post. Coins in your own wallet show up on your own node. Coins on a platform show up as a line in a filing. At the time of this writing, bitcoin was $77,306.