Coinbase (COIN) said Wednesday that it was not affected by the $6.3 billion hack at Binance, using the disclosure to outline how it protects customer funds in a company blog post. The announcement came less than a week after the Oct. 29 breach.

The exchange's headline figure: more than 99% of customer assets sit in cold storage, offline and cut off from the internet. Coinbase maintains only a small hot wallet balance to handle deposits and withdrawals, while the remainder stays offline and out of attackers' reach.

Cold storage reduces the amount of assets directly exposed to online attacks, but it is one part of a broader custody system. Access controls, withdrawal monitoring, key management and the procedures used to authorize transactions also matter when assets must move between offline and online environments.

The company reiterated the message in a post on X on November 4, 2026:

Users come to Coinbase to keep their money secure. We make sure that stays true. Secure custody is daily work for us, not a one-time achievement. That means 1:1 backing, >99% of funds in offline cold storage today, audited financials, key splits, no single points of failure and… — Coinbase 🛡️ (@coinbase) November 4, 2026

How Coinbase Says It Locks Down Funds

At the center of the company's custody model is multiparty computation, or MPC, which splits signing power among separate participants so that no single place ever holds a full private key. Withdrawal limits and unusual activity detection add further layers of protection, and Coinbase also maintains controls capable of halting transaction signing altogether.

Customers can enable additional safeguards of their own, including two-factor authentication and security keys. Coinbase Vault can require several approvals before a withdrawal goes through.

According to the company, customer assets are held 1:1 and remain customer property. Coinbase says it does not lend or use those funds without customer instruction. Its latest quarterly filing listed about $377 billion in platform assets, along with $8.6 billion in cash and $2.2 billion in corporate crypto.

The protections described cover hosted Coinbase.com accounts. People who use self-custody wallets remain responsible for guarding their own private keys.

What Happened at Binance

Binance says the attack began with a fake job interview, which gave hackers access to employee laptops. On Oct. 29, the attackers sent fraudulent withdrawal requests. Reports say they reached an internal wallet signing service and moved assets outside the normal process. Binance said Tuesday that the hackers also used an internal AI tool.

Coinbase's blog post pointed to AI as a growing threat to employees, systems and customers. The company builds its security software in-house; the Bybit and Bitget incidents, by comparison, reportedly involved outside vendor systems.

Coinbase has had its own security troubles. In 2025, criminals bribed overseas support agents to obtain customer data, and the company said the incident could cost as much as $400 million. The exchange also cites SOC 1 and SOC 2 Type II examinations and regulatory oversight among its credentials, while acknowledging that these steps do not rule out a breach.

Binance co-founder Changpeng “CZ” Zhao said crypto firms need AI-based defenses and an industry alliance, adding that he wants stolen funds frozen faster.

On Wednesday, Binance said it had replenished about 98% of the affected assets and is buying the remaining 2% through market and over-the-counter channels. The exchange also expanded its Proof of Reserves to 44 tokens, up from 10, and said its new zero-knowledge proof is expected to take 50 to 60 hours to generate.

This article originally appeared on CoinCentral.