When Ethereum completed its transition to Proof of Stake on September 15, 2022 — an event known as "The Merge" — Ethereum Classic became the largest Proof of Work smart contract platform. ETC's commitment to PoW was not a passive default but a deliberate choice rooted in the network's founding principles.
The Merge and Its Implications
Ethereum's Merge eliminated mining from its consensus mechanism, replacing it with a validator staking model. This transition had significant implications for censorship resistance:
- Validator concentration: A small number of large staking providers control substantial portions of the validator set
- Regulatory surface: Identifiable validators can be compelled by jurisdictions to comply with transaction filtering requirements
- OFAC compliance incidents: In the months following The Merge, a measurable percentage of Ethereum blocks were produced by validators complying with OFAC sanctions lists, temporarily excluding certain transactions
Why Proof of Work Matters
Proof of Work provides censorship resistance through physical decentralization:
Permissionless participation: Anyone with mining hardware and electricity can participate. There is no minimum stake, no approval process, and no identity requirement.
Geographic distribution: Mining operations are distributed globally, often in jurisdictions with minimal regulatory overlap. No single government can effectively control the majority of hash power.
Transaction inclusion guarantee: In PoW, miners are economically incentivized to include all fee-paying transactions regardless of content. Excluding valid transactions means forgoing fee revenue — a direct economic cost.
No slashing risk: PoW miners cannot have their equipment confiscated through protocol-level penalties. Validators in PoS systems face slashing, creating leverage for entities that can influence validator behavior.
ETC's Position
Ethereum Classic's commitment to Proof of Work predates The Merge. The network's monetary policy (ECIP-1017), immutability principles, and resistance to irregular state changes all reflect the same philosophy: protocol rules should be enforced by physics and economics, not by social consensus among identifiable parties.
After The Merge, ETC absorbed significant hash power from former Ethereum miners, further strengthening its security. The network continues to operate as a permissionless, censorship-resistant platform where transaction inclusion depends solely on paying the required fee — not on the sender's identity or the transaction's purpose.