A new proposal from blockchain startup AmericanFortress claims to offer a solution to one of the most pressing existential threats facing Bitcoin: the eventual advent of quantum computing. The company’s patent-pending post-quantum signature scheme aims to secure Satoshi Nakamoto’s legendary 1.1 million bitcoin stash, along with millions more tokens that have lain dormant for over a decade, without requiring mass fund migrations or wallet disruptions.
Quantum computing, while still in its infancy, poses a fundamental risk to cryptocurrencies that rely on elliptic curve cryptography (ECC). Bitcoin, like many other blockchains, uses ECDSA (Elliptic Curve Digital Signature Algorithm) to secure transactions. A sufficiently powerful quantum computer could theoretically break this cryptography, allowing an attacker to derive private keys from public keys and spend funds from any wallet whose public key has been revealed. This includes the early Bitcoin addresses created by Satoshi Nakamoto—addresses that predate hierarchical deterministic (HD) wallets and were never moved.
AmericanFortress CEO (name from original article omitted per instructions) explained in an exclusive interview that the company’s solution is designed to be backward-compatible, requiring only a soft fork and simple node and wallet updates. The core idea involves freezing vulnerable addresses—specifically those created before the introduction of BIP32 (hierarchical deterministic wallets)—and then using zero-knowledge proofs (ZKPs) to allow owners to prove ownership without exposing their public keys. This prevents quantum adversaries from intercepting the signature and deriving the private key.
“The beauty is that we don’t need everyone to move their coins,” said the CEO. “We can protect the dormant supply at the protocol level, preserving the network’s history and stability. Then, governance can decide what to do with those funds—whether to let the original owners reclaim them, burn them, or redistribute them.”
AmericanFortress has already raised an $8 million seed round to develop the technology. The firm’s multi-layer quantum defense integrates with existing consensus mechanisms and can be applied to major chains like Ethereum, Solana, and Tron in addition to Bitcoin. The startup claims that the performance impact is negligible—less than a 1% increase in block validation time—and that the security gain is immense.
The threat of quantum computing to cryptocurrencies is not new. In 2017, the US National Institute of Standards and Technology (NIST) began a process to standardize post-quantum cryptography. Bitcoin’s developer community has long debated how to transition to quantum-resistant signatures. Vitalik Buterin has discussed potential quantum forks for Ethereum. However, until now, no practical proposal had addressed the legacy stash of Satoshi and other early adopters.
Satoshi’s 1.1 million bitcoin—worth over $70 billion at current prices—has never moved since being mined in 2009. The owner’s identity remains unknown, but the coins are considered a “time bomb” for the market if they ever become spendable. A quantum attack could allow a malicious actor to seize those coins, potentially crashing the market. AmericanFortress’s approach would freeze those addresses, preventing any unauthorized movement and giving the network community time to decide on a proper course.
The proposal also covers other dormant wallets from the early era, which collectively hold tens of millions of coins. Many of these might belong to lost keys or deceased holders. By freezing them now, before quantum computers become powerful enough to exploit them, AmericanFortress argues that the crypto ecosystem can avoid a catastrophic security event.
Critics, however, question the centralization implications. A soft fork that freezes specific addresses requires broad miner and node acceptance. If a majority agrees, the chain would split. While backward compatibility ensures that transactions from non-frozen addresses remain unaffected, the act of freezing could be seen as a violation of Bitcoin’s immutability principle. The AmericanFortress team responds by framing it as a security upgrade similar to previous soft forks (like SegWit or Taproot) that were adopted voluntarily.
Moreover, the proposal includes a governance mechanism to eventually unfreeze the funds once quantum-resistant signatures are widely adopted. The exact mechanism—whether through a DAO, miner vote, or community consensus—remains to be finalized. AmericanFortress plans to release a detailed tokenomics and governance white paper later this year.
Beyond Bitcoin, the company is targeting other blockchains. Ethereum uses the same secp256k1 curve for its accounts, so a quantum attack could drain externally owned accounts (EOAs). Solana and Tron use different curves but face similar vulnerabilities. AmericanFortress’s solution can be adapted to each chain by modifying the soft fork rules and the ZKP circuit.
The $8 million seed round was led by undisclosed venture firms with a focus on deep tech and privacy. The funds will be used to hire cryptographic engineers, build a testnet, and conduct audits. AmericanFortress plans to launch a public testnet in Q3 2026, with a mainnet soft fork proposal for Bitcoin by Q1 2027.
The timeline is aggressive but necessary. Quantum computing advances are accelerating. In 2024, IBM unveiled a 1,121-qubit processor; Google and Microsoft are racing to build fault-tolerant quantum computers. While breaking 256-bit ECDSA still requires millions of logical qubits, the timeline could shrink with breakthroughs. Many experts estimate a 10- to 20-year window before quantum computers pose a practical threat to Bitcoin. That means the industry has time, but not indefinitely.
AmericanFortress’s proposal is not the first quantum defense plan. In 2019, a research paper suggested a “quantum fork” where all coins would be migrated to new addresses using post-quantum signatures. But that required every holder to actively move their funds—a near impossibility for lost or dormant wallets. Another approach, “quantum hard fork,” would involuntarily transfer funds to new addresses, which many saw as too disruptive. AmericanFortress’s soft-fork-freeze approach strikes a middle ground: it reserves the right to freeze without immediate movement, but leaves the door open for future redemption.
The startup also emphasizes that the zero-knowledge proofs used in the scheme do not require trusted setups. Instead, they rely on transparent zk-SNARKs, which have been proven secure in the blockchain context. This ensures that no trapdoor or backdoor can be introduced.
If successful, the proposal could be a landmark moment for crypto security. It would demonstrate that even foundational protocols like Bitcoin can adapt to emerging threats without breaking the core principles of decentralization and permissionlessness. The dormant coins—often considered a dead weight—could become a test case for collective governance.
Meanwhile, the crypto community remains divided. Some purists argue that Satoshi’s coins should never be touched, even for protection. Others see them as a systemic risk that must be neutralized. AmericanFortress is banking on the latter view, betting that pragmatism will win over ideology when the quantum threat becomes more tangible.
The company’s next milestone is a technical paper detailing the full protocol, expected in June 2026. That will be followed by an open-source implementation and community engagement across major cryptocurrency forums. The seed round will also fund a bug bounty program to ensure the cryptographic primitives are robust.
In a world where cybersecurity threats evolve rapidly, AmericanFortress’s proposal offers a proactive stance. Whether it gains the necessary consensus or joins the ranks of ambitious but unadopted upgrades remains to be seen. But for the first time, there is a concrete plan to save Satoshi’s legacy—and the billions of dollars it represents—from the quantum abyss.
As one industry observer noted, “Bitcoin’s greatest vulnerability is its oldest coins. Fixing that is not just about technology; it’s about trust in the system’s ability to evolve.” AmericanFortress is betting that trust can be engineered.
Source: Coindesk News