Ethereum Classic (ETC)

From CryptoWiki

Ethereum Classic
Ticker symbolETC
Consensus mechanismProof-of-Work
Total supply210,000,000 ETC


  • Hard forked on: 24-7-2016
  • Based in:


"A security malfunction written in The DAO’s smart contracts allowed hackers to steal over $50M worth of ETH during a poster child offering in late 2016. This resulted in the creation of a new primary Ethereum blockchain (the one we all know today) in which the hack was reversed alongside Ethereum Classic, in which the hack was never reversed."

Audits & Exploits


51% attacks

  • Many threats have been made by ETH redditors and also more well known miners that they would try a 51% attack on the ETC chain. So far, none of these threats have been acted out (8-2018)
  • Has been 51% attacked around 1-2019, Coinbase suspended ETC. There is no sign this attack was connected to the threats of 2017 though. Double spends did happen.
  • From this analyses (5-8-2020):

"In the last article, Ethereum Classic 51% Chain Attack Jul 31 2020, we have described the facts related to Ethereum classic attack, which took place between Jul 31 and Aug 1. Key Takeaway: Attacker double-spent 807,260 ETC ($5.6 million) during this attack and spent 17.5 BTC ($192K) to acquire the hash power for the attack. The attacker also got 13K ETC as a block mining reward, which we not including in our double-spent calculation."

  • "VeriBlock disclosed a vulnerability in Ethereum Classic’s MESS protocol which can result in network fracturing."






Coin Details

Coin Distribution


  • Whitepaper can be found [insert here].
  • Code can be viewed [insert here].
  • Programming language used:

Transaction Details

How it works





  • From CoinDesk (13-1-2020):

"Similar to the network’s last backwards-incompatible upgrade in September, Atlantis, Agharta makes ethereum classic more interoperable with sister-chain ethereum. As part of the hard fork, the Constantinople and St. Petersburg upgrades deployed in tandem on the ethereum network last February will be enabled under Ethereum Classic Improvement Proposal (ECIP) 1056.

Client diversity declining:

“The client diversity problem on ETC is in the opposite direction [of ETH], with Parity-Ethereum dominating,” Summerwill said in the ethereum AllCoreDevs Gitter channel. “Geth Classic is being deprecated and won't be supported after this pending fork, and it looks like most node operators are taking the advice and migrating off.

At time of writing, ethereum classic has 252 Parity Ethereum clients, 167 Geth Classic, 80 Multi-Geth and 1 Besu for a total of 500 clients. Ethereum classic developers, including Summerwill, expect the Multi-Geth and Besu clients to fill the gap.

Afri Schoedon, release manager at Parity Technologies and ethereum classic hard fork coordinator, told CoinDesk that client centralization is a small concern given the state of Geth Classic and available alternatives. Schoeden said Geth Classic has hardly been updated since its launch in 2016, leading to the deprecation.”


Different Implementations

  • There are 3 main clients: the nominally canonical “Classic-Geth” client (in Golang), Parity Labs’ eponymous software (in Rust) and IOHK’s Mantis in Scala.
  • OpenEthereum (the follow up for the Parity client) decided to stop development on the ETC client (20-7-2020):

"What this means is, of the 615 current Ethereum Classic nodes listed by ETC Nodes, 425 won’t update in the future as developers make changes via hard forks. That leaves Besu, with three nodes, and Core Geth, with 187, to support the network if a hard fork were to occur now. OpenEthereum supports 294 nodes and Multi-Geth supports 131 nodes. The former is a project run by decentralized exchange (DEX) Gnosis that supports Ethereum and Ethereum Classic implementations written in the Solidity programming language.

OpenEthereum has chosen to shut down support for the original Ethereum mainnet to conserve developer energy for its Ethereum client, formerly known as Parity-Ethereum. Gnosis’ OpenEthereum inherited the entire client codebase from Parity Technologies in December. In a private message, Gnosis Founder Martin Köppelmann told CoinDesk that Gnosis did not have the “capacity or the willingness to get involved into the governance (aka “drama”) of other chains.” 


Other Details

Oracle Method

Privacy Method


Their Other Projects


  • Can be found [Insert link here]


Projects that use or built on it


Pros and Cons



Dev Teams


  • At present (12-2018) most informal community discussion takes place on ETC’s Discord server, with ECIPs themselves posted on the nominated Github account (ethereumclassic) following a power struggle and takeover of the previous canonical Github account (ethereumproject), ostensibly related to the situation with ETCLabs.
  • When ETCdev ceased operation, the hitherto canonical client Classic-Geth written in Golang stopped being reliably maintained. ETCLabs Core maintains Multi-Geth but not all stakeholders in the ETC ecosystem are currently comfortable using their software given their ostensible desire to have an independent ECLIPimprovement proposal pathway which appears more hard-fork than soft-fork oriented.


The Ethereum Cooperative

  • The foundation (partly) responsible for the development of Ethereum Classic, is now a 501(c) non profit based in the USA.
  • Supports ChainSafe according to their website (as of 9-2019).



  • DCG/Grayscale and DFG fund ETC Cooperative. Since 2017, Grayscale has donated a total of $1.1 million, including $338,000 in 2019, to the cooperative. And it announced (22-1-2020) it will fund them for 2 more years.


  • Defunct, used to do ETC development, Emerald application development framework and tools, Orbita sidechains.
  • A leading Ethereum Classic, ETCDEV, development entity has shut down (3-12-2018) its operations; in a tweet from the ETCDEV announced that the company will halt development as a result of failure to raise enough funds and a market price crash; on the 2nd of December, the team at ETCDEV had asked the ETC community if they would be willing to help fund operations where 59% answered "no". The ETCDEV team maintains Classic Geth, the main client for the ETC blockchain. Also contributed to original projects, such as Emerald to help others develop on the ETC blockchain, Emerald Wallet for end users, and SputnikVM as a standalone, modular, embeddable and IoT ready EVM.
  • After the collapse of ETCdev, another entity “ETCLabs” was formed, a new developer team “ETCLabs Core” with significant overlap of personnel. "Some community members have described the sequence of events as a corporate takeover attempt, others do not seem so worried."


  • Is a for-profit company with VC/Startup and core development activities funded by DFG, DCG, IOHK and Foxconn.
  • After the collapse of ETCdev, another entity “ETCLabs” was formed, a new developer team “ETCLabs Core” with significant overlap of personnel. "Some community members have described the sequence of events as a corporate takeover attempt, others do not seem so worried."
  • Is working together (10-2-2020) with Fantom on Xar Network and it's DeFi aims.



  • On 24-5-2023 Charlessaid ETC had become a scam and he distanced himself and Ergo from it.
  • Hoskinson, Charles; dev team, his IOHK team that works on ETC can be viewed here
  • Charles Hoskinson supposedly is a dev for ETC. He is the founder of IOHK and subsequently Cardano and the Cardano Foundation. Hoskinson has a long history as a blockchain entrepreneur. He was initially the CEO of Ethereum before being fired. Reasons of the firing are complicated. Ethereum at the time was 6 months old with a $15 million market cap.
  • Hoskinson then founded IOHK and IOHK subsequently led the development of Ethereum Classic. Ethereum Classic came to be when Ethereum hard forked after the major DAO hack. A small portion of the community was against this idea and maintained the original chain, which is now known as Ethereum Classic. For IOHK to lead the development of Ethereum Classic suggests that Hoskinson might have some bad blood with members of the Ethereum Foundation, likely from earlier disagreements that resulted in his ousting.
  • While IOHK continues to lead Ethereum Classic’s development, its primary focus is now on Cardano. There has been resistance to adopt an on-chain treasury as proposed by IOHK, some stakeholders see this as inherently centralising.
  • From Cointelegraph (10-8-2020):

"Hoskinson recently offered to help the troubled Ethereum Classic (ETC) community, but it came with a major condition. The community would first have to institute a decentralized treasury system, similar to Hoskinson’s Cardano and many other blockchain projects. If the community did not accept his terms, Hoskinson felt like his help would have been a waste of time and money. Hoskinson lamented that despite him helping the Ethereum Classic community in the past, he has been treated unfairly by its leadership. Terry Culver, CEO of ETC Labs and ETC Core released this statement to Cointelegraph in response to Hoskinson’s offer: "As an open-source, decentralized community, we welcome all ideas and appreciate that so many people in the blockchain community have reached out to us. That said, we're not waiting for someone else to step in. We are a focused team who are passionate for ETC, and we will work diligently to ensure a bright future for ETC.""


  • Antpool announced it has invested $10 million in the proof-of-work Ethereum Classic ecosystem and plans to invest more (27-7-2022). This was kicked off by the looming Ethereum merge making PoW Ethereum miners obsolete there.


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