Analysts have proposed five stages and three scenarios for the future in terms of the quantum threat to the integrity of the Bitcoin network
Analysts at the investment firm ARK Invest, in collaboration with the research firm Unchained, have published a comprehensive study examining the impact of quantum computing on Bitcoin’s security. Contrary to widespread fears of a “quantum apocalypse” that would destroy the cryptocurrency, the experts offered an alternative perspective.
The study’s main conclusion is that the threat is real, but it is not immediate and will develop gradually. Furthermore, the analysts concluded that 65.4% of all bitcoins are already secure, and the community has at least a decade to protect the remaining 34.6%.
In their paper, the authors identified five stages of quantum computer development and, based on the uncertainty surrounding the timing of these stages, constructed three probable scenarios for the future of the first cryptocurrency. The experts’ conclusions and assumptions are based on several dozen scientific papers and expert comments.
*ARK Invest manages exchange-traded funds (ETFs), some of which invest in shares of crypto companies and funds, as well as one of the largest spot Bitcoin ETFs—the ARK 21Shares Bitcoin ETF, which held $2.5 billion in Bitcoin as of March 13. Company CEO Cathie Wood has been predicting for several years that the price of a single Bitcoin will exceed $1 million by 2030.
Until recently, the threat posed by quantum computers to cryptocurrencies was considered remote. However, in 2025, an increasing number of major players began to view this threat as a real market risk. The crux of the matter is that, in theory, quantum computers make it possible to gain control over a portion of Bitcoin addresses using an outdated format. This is not a “hack” in the conventional sense, but a loss of cryptographic protection, which potentially allows for the spending of other people’s coins.
In their analysis, ARK experts evaluated Bitcoin addresses, dividing them into categories based on their level of vulnerability to attacks by quantum computers. An analysis of the distribution of coins across addresses revealed the following picture:
- Secure bitcoins (65.4%, or approximately 13 million bitcoins): Modern address types, such as SegWit and others that employ best security practices, are resistant to quantum attacks at this stage.
- Vulnerable bitcoins that can be moved to other, more secure addresses (25%, or about 5 million bitcoins): coins held in addresses that have already been used for transactions or in certain older formats. Their owners can transfer funds to secure addresses as the threat approaches.
- Vulnerable and presumably lost bitcoins (8.6%, or about 1.7 million bitcoins): coins stored in the oldest type of address - P2PK (Pay-to-Public-Key). These date back to the network’s early years and, according to experts, may be permanently lost to their owners. This segment is theoretically the most attractive category for attackers.
The vast majority of lost coins are bitcoins believed to be held by Bitcoin’s anonymous creator, known as Satoshi Nakamoto. There is no reliable information on exactly how many coins he owns. However, the generally accepted estimate of his holdings is 1.1 million BTC: this figure is based on the work of researcher Sergio Damian Lerner, who found a probable “pattern” in Satoshi’s transactions, dubbed the Patoshi Pattern.
The authors of the study criticize the concept of a sudden attack by quantum computers and propose five stages leading up to it.
- Stage 0 (today): Quantum computers exist, but they are commercially useless and pose no threat to Bitcoin.
- Stage 1: Quantum computing becomes useful in a number of fields, such as chemistry. We are still a long way from breaking cryptography.
- Stage 2: Machines capable of breaking old cryptosystems and weak cryptographic keys appear.
- In Stage 3, a quantum computer cracks Bitcoin private keys in a matter of hours or days. Only coins in vulnerable address categories are at risk.
- Stage 4: Cracking a key takes minutes, and this is already a threat requiring an urgent protocol update.
The transition between stages will be a long one, according to ARK experts, who cited forecasts from Google, IBM, and Microsoft; the first key break (Stage 3) is not expected until the mid-2030s.
In addition to the five stages of development, analysts at ARK and Unchained suggested that investors consider three basic future scenarios covering the entire spectrum of potential technological breakthroughs.
- Optimistic scenario. The development of quantum computing is hindered by physical or engineering barriers, and the industry enters a “quantum winter.” Bitcoin gains decades to test and implement post-quantum cryptography without panic or controversy.
- Pessimistic scenario. A breakthrough, possibly accelerated by artificial intelligence technologies, occurs unexpectedly quickly, catching the entire world off guard. The community is forced to rush the implementation of unpolished solutions. A sharp conflict over vulnerable coins is possible, leading to a split in the Bitcoin network. However, Bitcoin will survive this thanks to the protocol’s protection, backed by massive mining power.
- Base-case scenario. There are 10–20 years left before a real threat emerges. Quantum computers first become commercially viable (Stage 1), fostering an objective attitude toward the risks of developing these technologies. Developers have enough time to adapt, develop, or implement new algorithms for protection. In Stage 2, experts estimate that the community will agree on a protocol update that will introduce quantum-resistant address types. However, even in this scenario, disputes and volatility in the Bitcoin price are likely.
*Trade $BTC on OKX, special bonuses from us: https://okx.com/join/w3lab
