Ethereum Classic History

Network Upgrades

Every ETC network upgrade follows the same process: ECIP specification, independent client implementation, testnet validation, and mainnet activation. Olympia, a proposal, would draw its EIPs from London, Dencun, Pectra, Fusaka and Glamsterdam, carrying EVM alignment through Fusaka and into Glamsterdam.

Olympia

PROPOSED

ECIP-1111 ECIP-1112 ECIP-1121

A proposal, targeted for mainnet activation in 2027, with draft ECIPs and the activation block TBD: EVM alignment through Fusaka and into Glamsterdam, and an EIP-1559 base fee credited to a treasury.

EIP-1559 and EIP-3198, with the base fee credited to the Sovereignty Vault address (ECIP-1111)The Treasury at that address, and Olympia DAO to govern it, deployed before the fork (ECIP-1112, ECIP-1113)EVM alignment through Dencun, Pectra and Fusaka, carried into Glamsterdam (ECIP-1121)Block rewards and priority-fee tips unaffected

Olympia: Proposed · Draft ECIPs · Activation block TBDCountdown to December 31, 2027, a placeholder target

MESS Default: Off

Block 19,250,000Feb 5, 2024ECIP-1110

ECBP-1110 recommends that clients ship MESS (ECBP-1100) off, and Core-Geth v1.12.x releases carrying it switch MESS off from the Spiral block, as sustained hashrate growth removed the conditions MESS was introduced to mitigate. Both are Best Practice documents, not consensus rules, and MESS never decides whether a block is valid. Core-Geth v1.13.0 ships MESS on by default, because every v1.12 node on the network carried severe vulnerabilities when it was released. v1.13.1 turns it off by default again, and a build from source of the main branch already does.

ECBP-1110 recommends shipping MESS offActivated at the same block as SpiralA Best Practice, not a consensus rule

Spiral

Block 19,250,000Feb 5, 2024ECIP-1109

Aligned ETC with Ethereum's Shanghai upgrade (execution layer changes only).

EIP-3651 (warm COINBASE)EIP-3855 (PUSH0 instruction)EIP-3860 (limit/meter initcode)EIP-6049 (deprecate SELFDESTRUCT)

Mystique

Block 14,525,000Feb 12, 2022ECIP-1104

Aligned ETC with Ethereum's London upgrade (excluding EIP-1559, EIP-3198 and EIP-3554).

EIP-3529 (reduced SELFDESTRUCT and SSTORE gas refunds)EIP-3541 (reject new 0xEF contracts)EIP-1559 deferred to Olympia (delivered by ECIP-1111)EIP-3198 deferred with it (BASEFEE opcode depends on EIP-1559)+1 more

Magneto

Block 13,189,133Jul 24, 2021ECIP-1103

Aligned ETC with Ethereum's Berlin upgrade.

EIP-2565 (ModExp gas cost)EIP-2718 (typed transactions)EIP-2929 (gas cost increases for state access)EIP-2930 (access lists)

Thanos

Block 11,700,000Nov 28, 2020ECIP-1099

Doubled the DAG epoch length, halving the DAG's growth so consumer GPUs could keep mining ETC.

Etchash algorithm (modified Ethash)DAG epoch length doubled (30,000 → 60,000)Slower DAG growth, keeping 3GB and 4GB GPUs mining longer

MESS Default: On

Block 11,380,000Oct 11, 2020ECIP-1100

Modified Exponential Subjective Scoring (ECBP-1100) enabled by default, giving operators a tool to reduce the risk of deep chain reorganizations after the 2020 51% attacks.

MESS enabled by default (ECBP-1100)Penalizes deep chain reorganizationsClient-side defense, not a consensus rule

Phoenix

Block 10,500,839May 31, 2020ECIP-1088

Aligned ETC with Ethereum's Istanbul upgrade.

EIP-152 (Blake2b precompile)EIP-1108 (bn256 gas reduction)EIP-1344 (CHAINID opcode)EIP-1884 (repricing for trie-size-dependent opcodes)+2 more

Agharta

Block 9,573,000Jan 12, 2020ECIP-1056

Aligned ETC with Ethereum's Constantinople and Petersburg upgrades.

EIP-145 (bitwise shifting)EIP-1014 (CREATE2)EIP-1052 (EXTCODEHASH)

Atlantis

Block 8,772,000Sep 12, 2019ECIP-1054

Aligned ETC with Ethereum's Spurious Dragon and Byzantium upgrades.

EIP-161 (state trie clearing, from Spurious Dragon)EIP-170 (contract code size limit, from Spurious Dragon)EIP-100 (difficulty adjustment)EIP-140 (REVERT opcode)+5 more

Defuse Difficulty Bomb

Block 5,900,000May 29, 2018ECIP-1041

ECIP-1041 permanently removed the difficulty bomb from ETC, ensuring stable block times.

Difficulty bomb permanently removedStable block times preservedNo forced upgrade pressure

Gotham

Block 5,000,000Dec 11, 2017ECIP-1017

ECIP-1017 monetary policy: the 210.7 million ETC supply cap with era-based emission reduction.

Fixed monetary policy (supply cap ~210.7M ETC)Era-based emission reduction (20% per era)Five million block eras

Die Hard

Block 3,000,000Jan 13, 2017ECIP-1010

Replay protection and a delay of the difficulty bomb.

EIP-155 (replay protection)EIP-160 (EXP gas cost increase)Difficulty bomb delay

Gas Reprice

Block 2,500,000Oct 25, 2016ECIP-1015

EIP-150 repriced I/O-heavy opcodes for DoS protection after the Shanghai attacks.

EIP-150 (gas cost increases for I/O operations)DoS attack mitigationCALL gas cost increase

DAO Fork (Rejected)

Block 1,920,000Jul 20, 2016

Ethereum forked to reverse the DAO hack. ETC rejected the irregular state change and continued the original chain.

ETC continued the original unaltered chainEthereum Classic identity establishedCode is law principle preserved

Homestead

Block 1,150,000Mar 14, 2016

First major planned upgrade: EIP-2, EIP-7, EIP-8.

EIP-2 (transaction validity rules)EIP-7 (DELEGATECALL opcode)EIP-8 (devp2p forward compatibility)

Frontier Thawing

Block 200,000Sep 7, 2015

Increased gas limit from 5,000 to enable meaningful transactions and contract deployment.

Gas limit increaseDifficulty bomb introducedEnabled contract deployment

Frontier

Block 1Jul 30, 2015

Genesis block: the Ethereum network launches.

Initial network launchGas limit of 5,000 per blockProof-of-Work consensus