1. The Quantum Threat to Bitcoin

Quantum computing poses a significant but not immediate threat to Bitcoin's cryptographic foundations. As of July 2026, research indicates that while current quantum hardware cannot yet break Bitcoin's 256-bit encryption, the timeline for a "Cryptographically Relevant Quantum Computer" (CRQC) has compressed. Galaxy Digital has positioned itself as a primary institutional leader in addressing this risk, launching a $5 million readiness initiative on July 21, 2026.

1. The Quantum Threat to Bitcoin

The primary vulnerability lies in Bitcoin’s use of the Elliptic Curve Digital Signature Algorithm (ECDSA). A sufficiently powerful quantum computer using Shor’s Algorithm could derive a private key from a public key, allowing an attacker to forge signatures and drain funds.

• Vulnerable Supply: Approximately 6.9 million BTC (~35% of circulating supply), valued at roughly $461 billion, is considered at risk because the public keys for these addresses are already exposed on the blockchain (e.g., legacy P2PK addresses or reused P2PKH addresses) [Source: https://www.coindesk.com].
• Attack Windows: Beyond "at-rest" coins, research from Google Quantum AI (March 2026) suggests a theoretical "on-spend" attack could intercept and solve a transaction's public key in as little as 9 minutes, potentially within Bitcoin's 10-minute block confirmation window [Source: https://quantumai.google].
• Timeline: Expert consensus for a CRQC ranges from the early 2030s to mid-century. However, Google has set an internal post-quantum cryptography (PQC) migration deadline for 2029, and NIST finalized PQC standards in 2024 [Source: https://quantumai.google].

2. Galaxy Digital's Preparedness

Galaxy Digital (NASDAQ: GLXY) is proactively leading the institutional response through the Galaxy Bitcoin Quantum Readiness Initiative, announced in July 2026.

3. Protocol-Level Defenses

The Bitcoin developer community is already integrating defenses:

• BIP-360: Merged in February 2026, this introduces quantum-resistant "bc1z" address types (Pay-to-Merkle-Root) [Source: https://bitcoinmagazine.com].
• BIP-361: A phased migration plan published in April 2026 that proposes sunsetting vulnerable legacy signatures over a 5-year period, including a ZK-proof recovery path for lost keys [Source: https://bitcoinmagazine.com].
• Recovery Tools: Project Eleven unveiled a ZK-proof prototype in July 2026 that allows users to prove wallet ownership via parent key derivation even after signatures are compromised, running in just 243 milliseconds [Note: not independently confirmed].

Summary of Key Metrics

While the threat of signature reversion via Shor's algorithm is well-documented, there is currently no evidence that quantum computers can efficiently cause SHA-256 hash collisions to compromise Bitcoin's mining process. Galaxy Digital appears ready from a research and funding perspective, though actual protocol implementation remains a long-term community effort.