Harmony plans to move ONE to Ethereum and shut mainnet

Harmony has proposed closing its seven-year-old Layer 1 blockchain, issuing ONE on Ethereum and directing future token emissions to a new AI video project.

Harmony said in a Sept. 6 post that the mainnet’s exposure to “state actors” and “AI agents” has made continued operation too risky, leading the team to propose retiring the network it launched in 2019.

The plan remains nonbinding, and Harmony has not announced when it will produce the blockchain’s final block. The team also has not explained whether validators will decide the proposal through the network’s existing governance process.

Under Harmony’s published governance rules, a proposal must receive votes representing at least 51% of total stake weight. Approval requires support from 66.7% of the participating voting power after a seven-day introduction period and a 14-day vote.

Harmony would recreate ONE balances on Ethereum

Rather than asking holders to exchange their tokens manually, Harmony plans to take a snapshot at the final block and distribute replacement ONE tokens on Ethereum. The ERC-20 version would go to the same addresses recorded in the snapshot, removing the need for individual claims.

The snapshot would cover ONE held in personal wallets, staking delegations, unclaimed validator rewards, smart contracts, and centralized exchange accounts. Harmony plans to coordinate with exchanges so that their existing ONE listings can move to the Ethereum-based token.

Delegated tokens and unpaid validator rewards would be handled separately through individual governor vaults. According to the proposal, the total ONE supply and its scheduled issuance rate would remain unchanged during the transition.

To allow outside review of the process, Harmony said it would publish the Ethereum token contract, snapshot calculations, and airdrop scripts. The project has not yet released the contract address or the final snapshot method.

While ordinary wallet balances would be included automatically, several types of holdings cannot be copied to Ethereum in their current form. Harmony said multisignature vaults, liquidity pools, and applications running on the mainnet would not migrate with the token balances.

Users have therefore been asked to withdraw from smart contracts before Sept. 10. Anyone who leaves assets inside a decentralized exchange pool, lending market, or another on-chain application could face complications because the protocol state and its related contracts will not be recreated on Ethereum.

For centralized exchange customers, the process will depend partly on each platform’s support for the migration. Harmony has proposed moving exchange-held balances and listings to the ERC-20 token, although it has not published a list of participating exchanges or their individual timetables.

Validators face separate shutdown conditions

Beginning Sept. 10, validators would be allowed to turn off their nodes as the network prepares for its final block. Harmony has set aside $1.372 million for eligible validators and their delegators, with payments scheduled across four quarterly installments.

Eligibility carries several conditions. Validators must stop their nodes within the required period, retain their stakes, sign an agreement, and continue serving as governors after the mainnet closes. The pool would also cover the difference between the rewards earned at a validator’s last block and the rewards it would have received through the final network block.

Harmony has not disclosed how the $1.372 million will be divided among validators and delegators. Final payments may depend on stake levels and compliance with the proposed agreements, according to the terms described by the team.

Operators could later remain in governance or join Harmony’s planned “remix economy” as operators or affiliates. Future ONE emissions would fund the new AI video initiative, although Harmony said governors could still provide feedback on the arrangement.

Under the proposed model, video creators would publish prompts and related assets that fans could copy and alter. AI agents would turn the resulting branches into additional clips, while operators would manage video generation, distribution and content moderation.

Harmony said staking levels and service uptime would affect operator rewards. The project also plans to subsidize graphics processing hardware during the first year and has projected up to $1 million in combined operator revenue, subject to the service and staking requirements.

The business model includes a proposed $10 monthly subscription. Affiliates would receive a recurring 30% commission from users they refer, while Harmony estimated that advertising could produce tens of millions of dollars if the platform reached 1 million users. Both revenue figures remain projections from the project rather than confirmed income.

August exploit pushed Harmony toward a shutdown

The retirement proposal follows an August security breach that produced unauthorized ONE tokens and forced the team to consider reversing several days of blockchain activity.

On Aug. 12, crypto.news reported an unauthorized mint after on-chain researcher Juiceberg estimated that almost 4 billion ONE had been created through empty blocks. The researcher claimed that about 2.8 billion tokens reached centralized exchanges, but Harmony had not confirmed either figure when it first disclosed the incident.

Harmony’s later investigation found that more than 3 trillion ONE had been generated through six transactions. The team linked the exploit to a weakness in cross-shard receipt verification that allowed valid receipts to be processed repeatedly without matching deductions elsewhere on the network.

One wallet connected to the activity attempted 534 transfers of 5 billion ONE within 106 seconds, according to Harmony’s reconstruction. Of the attempted transfers, 477 succeeded and moved a combined 2.385 trillion ONE.

Investigators traced the created tokens to standalone wallets, exchange accounts, decentralized exchange routers, liquidity pools, bridge contracts, wrapped ONE and staking wallets. Harmony said it contacted exchanges, bridges, and law-enforcement agencies while tracking the assets.

By Aug. 17, the team had proposed returning both network shards to checkpoints recorded at 11:25:37 p.m. UTC on Aug. 11. Shard 0 would keep block 92,730,034 and restart from the next block, while shard 1 would return to block 94,978,278 despite not being the origin of the unauthorized mint.

The rollback would remove 141,628 consecutive blocks from shard 0, including 109,126 regular transactions and 315 staking transactions. Harmony classified 104,545 of the regular transactions, or 95.8%, as automated activity, with almost 100,000 tied to decentralized exchange automation.

At the time, the team considered migration but said it would cause more disruption than a rollback. Less than a month later, moving ONE to Ethereum became part of the proposed mainnet closure.

U.S. holders may need detailed migration records

For U.S. token holders, the migration may create tax-record concerns even if Harmony distributes ERC-20 ONE automatically. The IRS treats digital assets as property and requires taxpayers to report sales, exchanges, and other taxable disposals.

IRS guidance says exchanging one digital asset for another that differs materially in kind or extent can produce a capital gain or loss. Harmony describes the replacement as the same ONE token with unchanged supply and emissions, but the agency has not issued guidance addressing this specific mainnet-to-Ethereum migration.

U.S. holders may therefore need to preserve their original purchase records, wallet history, the final Harmony snapshot, and the value of the Ethereum token when received. Exchange customers should also retain any migration notices and Form 1099-DA information supplied by their platforms, since the IRS says taxpayers remain responsible for reporting taxable activity even when a broker does not provide a form.

Harmony had faced security problems before the August incident. In December 2023, the project disclosed that faulty staking logic had created 146.28 million ONE across 74 delegator addresses, prompting an emergency hard fork at block 51,118,080.

Its largest earlier loss came in June 2022, when attackers stole nearly $100 million from the Horizon cross-chain bridge after gaining control of keys used by its multisignature wallet. Harmony responded by raising its hacker bounty to $10 million and working with exchanges, analytics firms, and law enforcement.

A month after the bridge attack, developers proposed minting 4.97 billion ONE to reimburse affected users over three years. Community members opposed the resulting dilution, and Harmony later withdrew the plan in favor of a recovery program that would not add tokens through a hard fork.