Solana beats Bitcoin on coalition size, client risk high

ARK Invest and Glassnode published a Sept. 1 scorecard that measured how many block-producers or validators must coordinate to cross key control thresholds. The report set the threshold at three entities for Bitcoin and Ethereum and 19 for Solana, and placed Bitcoin first in a composite decentralization ranking.

The report used a metric it calls the critical resilience threshold. For Bitcoin the measure weights hash rate attributed to mining pools. For Ethereum and Solana the measure weights delegated stake and groups validators by owner, operator or protocol. Protocol rules then determine what a given share of power can do on each chain.

A seven-day Bitcoin snapshot on Sept. 6 attributed 26.88% of blocks to Foundry USA, 16.91% to AntPool and 15.25% to F2Pool. Those three pools accounted for 59.04% of observed block production, consistent with the report’s three-pool result. The report also notes that individual miners can switch hash power quickly; a roughly 1% position could be abandoned in about 30 seconds by turning off hardware, making pool concentration a short-term template-selection and censorship risk.

For Ethereum, a validator analytics view on Sept. 6 listed Lido at 21.17%, SSV at 16.56% and Binance at 7.77%. The analytics view described Lido as representing hundreds of underlying operators. The report referenced protocol thresholds that define attack effects: about 33% of stake can delay finality, more than 50% can censor transactions and control short-range fork choice, and at least 66% can finalize a preferred chain and alter finalized history. Validator exit is rate-limited; the report estimated exit times of weeks under stress but a live beaconchain snapshot on Sept. 6 showed an empty exit queue and a withdrawal estimate near one day.

Solana’s reported coefficient varied across sources. ARK and Glassnode reported 19, a network dashboard showed 18 on Sept. 6, and the Solana Foundation’s health report using April 2025 data recorded 20. These figures count the fewest validators whose combined stake reaches roughly one-third of voting power. The report highlights that shared ownership, delegation sources, hosting concentration, jurisdiction and client software all affect whether a coalition can censor blocks or stop consensus.

Infrastructure and client software create concentrated exposures on Solana. The Solana Foundation’s April 2025 data listed more than 100 hosting providers and found TeraSwitch and Latitude together hosting 45.70% of stake; a broader network view reported 437 data centers. On client diversity, the foundation recorded about 92% of stake using Agave/Jito in April 2025, and about 7% using Firedancer or a hybrid Frankendancer. For Ethereum, an observed execution-client share showed Geth at around 50%.

Node and hosting statistics varied by measurement method. The joint report cited roughly 63% of Bitcoin nodes operating behind Tor, while another crawler showed 12,959 Tor nodes among 26,837 reachable nodes on Sept. 6, or 48.3%. Ethereum hosting on Amazon Web Services also varied across datasets. The report recommended that institutions map specific exposures: concentration of stake or hash rate for censorship and finality risks, validator and node mappings by provider and jurisdiction for legal or infrastructure pressure, client-share analysis for software bugs, and ownership and withdrawal timing for persistent capture.

The composite ranking in the scorecard favored Bitcoin after combining measures of auditability, ownership dispersion, geographic resilience and exit fluidity with block-production concentration. The report presented Solana’s higher validator count as a narrow measure of coalition size while noting other clustered dependencies identified in its analysis.