ECIP 1066: Ethereum Classic Network Description
| Author | Bob Summerwill, Christopher Mercer, meowsbits, Wei Tang |
|---|---|
| Status | Active |
| Type | Meta |
| Created | 2019-10-07 |
This document records the hardforks, network upgrades, and other consensus-relevant events in Ethereum Classic mainnet’s history, along with each entry’s activation block, governing ECIP, included EIPs, and contextual notes.
| <div align="center">Block No.</div> | <div align="center">Upgrade Name</div> | <div align="center">Release Date</div> | <div align="center">Specs</div> | <div align="center">Included EIPs</div> | <div align="center">Notes</div> |
|---|---|---|---|---|---|
| <div align="right">19,250,000</div> | Spiral Shanghai |
2024-02-04 | ECIP-1109 | Shanghai: EIP-3651, EIP-3855, EIP-3860, EIP-6049 | Aligned with Ethereum’s Shanghai upgrade (execution-layer subset only; no PoS-related withdrawal EIPs apply to ETC) |
| <div align="right">19,250,000</div> | MESS Default: Off ECBP-1110 |
2024-02-04 | ECIP-1110 | None | MESS defaults to disabled |
| <div align="right">14,525,000</div> | Mystique London |
2022-02-12 | ECIP-1104 | London: EIP-3529, EIP-3541 | Aligned with Ethereum’s London upgrade (execution-layer subset only; deferred base fee to a later upgrade) |
| <div align="right">13,189,133</div> | Magneto Berlin |
2021-07-23 | ECIP-1103 | Berlin: EIP-2565, EIP-2718, EIP-2929, EIP-2930 | Aligned with Ethereum’s Berlin upgrade |
| <div align="right">11,700,000</div> | Thanos ECIP-1099 |
2020-11-28 | ECIP-1099 | None | Doubled the Ethash epoch length (introducing “Etchash”) to align DAG growth with consumer GPUs and ASIC hardware |
| <div align="right">11,380,000</div> | MESS Default: On ECBP-1100 |
2020-10-09 | ECIP-1100 | None | MESS defaults to enabled. Introduced the Modified Exponential Subjective Scoring (MESS) flag in the client providing operators with a tool to lower deep chain reorganizations risk. |
| <div align="right">10,500,839</div> | Phoenix Istanbul |
2020-06-01 | ECIP-1088 | Istanbul: EIP-152, EIP-1108, EIP-1344, EIP-1884, EIP-2028, EIP-2200 | Aligned with Ethereum’s Istanbul upgrade |
| <div align="right">9,573,000</div> | Agharta Constantinople+Petersburg |
2020-01-11 | ECIP-1056 | Constantinople+Petersburg: EIP-145, EIP-1014, EIP-1052 | Aligned with Ethereum’s Constantinople+Petersburg upgrade |
| <div align="right">8,772,000</div> | Atlantis Byzantium |
2019-09-12 | ECIP-1054 | Spurious Dragon: EIP-161, EIP-170 Byzantium: EIP-100, EIP-140, EIP-196, EIP-197, EIP-198, EIP-211, EIP-214, EIP-658 |
Aligned with Ethereum’s Byzantium upgrade; also includes EIP-161/EIP-170 from Spurious Dragon |
| <div align="right">5,900,000</div> | Defuse Difficulty Bomb ECIP-1041 |
2018-05-29 | ECIP-1041 | None | A long-term commitment to Proof-of-Work (PoW) by removing the difficulty bomb. A clear differentiation from ETH’s PoS roadmap. |
| <div align="right">5,000,000</div> | Gotham ECIP-1017 |
2017-12-11 | ECIP-1017 ECIP-1039 |
None | Introduced ETC’s fixed, disinflationary monetary policy (ECIP-1017) and further delayed the difficulty bomb (ECIP-1039) |
| <div align="right">3,000,000</div> | Die Hard Spurious Dragon |
2017-01-13 | ECIP-1010 | Spurious Dragon: EIP-155, EIP-160 | Aligned with Ethereum’s Spurious Dragon upgrade; EIP-155 replay protection gave ETC its own chain ID (61), value derived from SLIP-44, distinct from ETH’s (1) (EIP-161/EIP-170 deferred to Atlantis) |
| <div align="right">2,500,000</div> | Gas Reprice Tangerine Whistle |
2016-10-24 | ECIP-1015 | Tangerine Whistle: EIP-150 | Aligned with Ethereum’s Tangerine Whistle upgrade (EIP-150), repricing IO-heavy opcodes in response to the fall-2016 DoS attacks on the network |
| <div align="right">1,920,000</div> | 2016-07-20 | HFM-779 | Rejected on ETC | The original (unforked) chain was later rebranded by the community as Ethereum Classic (ETC); the new, forked chain retained the Ethereum Foundation’s trademark and continued as Ethereum (ETH). Blog | |
| <div align="right">Aborted</div> | DAO Wars | Aborted | Aborted | Aborted | Blog |
| <div align="right">1,150,000</div> | Homestead | 2016-03-14 | HFM-606 | Homestead: EIP-2, EIP-7, EIP-8 | Blog |
| <div align="right">200,000</div> | Frontier Thawing | 2015-09-07 | Genesis | None | Blog |
| <div align="right">1</div> | Frontier | 2015-07-30 | Genesis | None | Blog |