ARK Invest and Glassnode published a 32-page joint study on Sept. 1 titled "The Decentralization Spectrum: Design Tradeoffs in Digital Assets," comparing Bitcoin, Ethereum and Solana across ownership, exit fluidity, verification costs, critical resilience, reconstruction costs and infrastructure distribution. The report ranked Bitcoin most decentralized overall, followed by Ethereum and Solana. Under measured block-production thresholds, three entities could cross critical levels for Bitcoin and Ethereum, while Solana required 19 validators, yielding Nakamoto coefficients of 3, 3 and 19. Bitcoin's Foundry USA, AntPool and F2Pool together exceeded 61% of hash rate under a 51% threshold; Ethereum's Lido, Binance and Kraken held about 38.8% of staked ETH under a 33% finality-disruption threshold. The figures treat pools and staking platforms as entities even when underlying miners or operators can leave, with a 1% Bitcoin hash-rate shift estimated at about 29 seconds versus roughly 14.6 to 55.6 days to exit 1% of Ethereum stake. Hardware for verification was estimated at $202 for Bitcoin, $730 for Ethereum and $21,478 for a Solana RPC or validator-class setup, with chain storage of 753 gigabytes, about two terabytes and 480 terabytes respectively. Solana's stake was more widely spread among validators but nearly all measured infrastructure sat in commercial data centers—about 68% in Europe—with a TeraSwitch routing problem in August stopping votes from 102 of 699 validators. The authors present the work as a map of separate concentration risks rather than a single definitive ranking.