Mining Pool Decentralization

Mining pool decentralization refers to the goal of distributing control over Bitcoin block construction across many independent miners rather than concentrating it in a handful of pool operators. The concern arises because the largest pools have at times collectively controlled well over half of network hashrate, with one or two pools alone approaching or exceeding 50% of blocks mined in recent years.

Why concentration matters

In the traditional Stratum V1 setup, the pool operator builds the block template, deciding which transactions to include and in what order, and connected miners simply hash whatever template they are given. This means transaction-selection power, and therefore any ability to censor or reorder transactions, rests with a small number of operators even though the hashrate is owned by thousands of independent miners. Concentration also raises theoretical 51%-attack and coordination risks.

Approaches to redistribute control

Two notable protocols aim to give individual miners back the power to build their own block templates while still pooling rewards: Stratum V2's job-declaration sub-protocol and OCEAN's DATUM. In both, a miner running a full node selects transactions from its own mempool and proposes that template to the pool, so censorship resistance no longer depends on trusting the operator. Adoption is still early, but the direction is toward separating reward-sharing from template control.

See Stratum V2 and OCEAN for the main implementations.

Measure it live in the pool centralization tracker (Nakamoto + HHI).