Coinbase founder and CEO Brian Armstrong has denied speculation that the company has sold paper bitcoin to BlackRock without maintaining a 1:1 support. In a statement to cryptocurrency analyst Tyler Durden published on X, Armstrong explained that the minting and destruction of bitcoin in the BlackRock Spot Bitcoin ETF is transparent and on-chain. Durden shared data from Cryptoquant showing that Coinbase is the largest buyer and seller at market highs and lows. In addition, he hinted that the exchange would allow BlackRock to borrow bitcoin without providing collateral. Since BlackRock is one of the world's largest bitcoin holders, the analyst said the two companies could profit by controlling the decline and rise of cryptocurrencies.