Ethereum Classic History

Network Upgrades

Every ETC network upgrade follows the same process: ECIP specification, independent client implementation, testnet validation, and mainnet activation. Olympia brings EVM alignment through Glamsterdam with EIPs spanning London, Dencun, Pectra, Fusaka, and Glamsterdam.

Olympia

UPCOMING

ECIP-1111 ECIP-1112 ECIP-1121 ECIP-1122

EVM alignment through Glamsterdam: EIPs spanning London, Dencun, Pectra, Fusaka, and Glamsterdam. Introduces EIP-1559 fee market with basefee directed to protocol treasury.

EIP-1559 dynamic basefee (directed to treasury)EVM parity with Ethereum through GlamsterdamEIPs from London, Dencun, Pectra, Fusaka, and GlamsterdamProtocol treasury funding mechanism+2 more

Olympia Countdown

0d0h0m0s

MESS Default: Off

Block 19,250,000Feb 4, 2024ECIP-1110

MESS (ECBP-1110) switched off by default at the Spiral block, as sustained hashrate growth removed the conditions it was introduced to mitigate. ECIP-1122 re-enables it at the Olympia block.

MESS disabled by default (ECBP-1110)Activated at the same block as SpiralRe-enabled at Olympia by ECIP-1122

Spiral

Block 19,250,000Feb 4, 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-3228).

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 23, 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

Halved the DAG size epoch length, enabling consumer GPUs to continue mining ETC.

Etchash algorithm (modified Ethash)DAG epoch length doubled (30,000 → 60,000)GPU mining accessibility preservedASIC resistance maintained

MESS Default: On

Block 11,380,000Oct 9, 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 10,500,839Jun 1, 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 11, 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 difficulty bomb delay. The first ETC-specific hard fork.

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

Gas Reprice

Block 2,500,000Oct 24, 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