Glossary / Privacy & security
Rehypothecation
- Definition
- Rehypothecation is a custodian lending out, pledging, or trading the bitcoin you deposited, so the coins backing your account balance are working somewhere else entirely.
The word comes from securities lending, where a broker reuses collateral a client pledged. Celsius Network ran the crypto version at retail scale, and its bankruptcy court found that roughly 4.2 billion dollars sitting in customer Earn accounts had become property of the estate. An advertised yield on bitcoin is the sound of this happening.
How it works
Rehypothecation starts with a sentence in a terms-of-use document, not with a break-in.
Hypothecation is pledging an asset as collateral while still owning it. Rehypothecation is the party holding that collateral putting it to work again: lending it to a trading desk, posting it against its own borrowing, or using it to make a market. Traditional finance does this under position limits and disclosure rules. Crypto lenders did it under a checkbox.
The legal switch is ownership. Celsius Network's Terms of Use granted the company "all right and title" to assets placed in Earn accounts, and on January 4, 2023 Judge Martin Glenn held that those terms formed an enforceable contract, meaning the deposits belonged to the bankrupt estate rather than to the 600,000 or so account holders. The same company also ran Custody accounts, which were treated differently precisely because their terms were different. Two balances, one app, opposite outcomes.
Why it breaks is a maturity mismatch, and it is the oldest failure in banking. Deposits are redeemable on demand. The loans made against them are not. A withdrawal wave forces the custodian to recall loans that cannot be recalled, and the queue closes.
Nothing here requires fraud. A platform can disclose everything, price the risk fairly, and still fail, because the yield you were paid was the fee for a risk you were carrying without noticing.
Where you see it
Rehypothecation hides inside any product that pays you a return for leaving bitcoin somewhere.
Earn, Interest, and Flexible Savings products. Bitcoin generates no native yield. It has no dividend, no coupon, and no staking reward. A percentage return therefore means someone is lending your coins to someone else, and the only question is who and on what collateral. BlockFi paid 100 million dollars in February 2022 to settle federal and state charges over its unregistered interest accounts, then filed for Chapter 11 on November 28, 2022. Genesis Global Capital halted withdrawals on November 16, 2022; the SEC charged Genesis and Gemini in January 2023 over the Gemini Earn program, which had roughly 340,000 investors.
Margin and lending balances at ordinary exchanges. Coins in a margin-enabled account are frequently usable by the venue as collateral. This is usually documented, rarely read, and the relevant clause is often in a separate margin agreement rather than the main terms.
"Institutional custody" that is really a broker relationship. Ask whether assets are held in a segregated, bankruptcy-remote structure or on the platform's own balance sheet. The answer changes where you stand in a queue of creditors.
The practical test takes two minutes. Search the terms of use for the words "title", "lend", "pledge", "hypothecate", and "commingle". If the platform takes title, the coins are not yours in any sense a court will recognize, no matter what the balance screen says. If the product pays interest, assume rehypothecation until the disclosure says otherwise.
The response is not to find a safer yield. It is to keep only a working balance on any platform and move the rest to a wallet whose keys you hold, where there is no counterparty to lend anything to.