What is a private key? Ownership, custody and safety
A private key is a secret number that proves ownership of a crypto address and authorises every transaction from it — whoever knows the key controls the coins. You can hold it yourself or let a custodian hold it for you, and no legitimate desk will ever ask you to reveal it.
KEY FACTS
| Term | Private key: the secret that controls a crypto address |
|---|---|
| Size | 256 bits, about 1.16 × 10^77 possible keys |
| Backup format | Seed phrase of 12 or 24 words (BIP-39) |
| Rule when selling | Never share the key; you sign the transfer yourself |
| IWGT flow | From ~100,000 USDT; your keys until settlement |
Source: BIP-39 specification and IWGT published flow, as of September 2026.
How a private key works
A private key is a randomly generated 256-bit number from which the public address is derived and with which every transaction is signed; the network verifies the signature, not your identity. Your wallet stores the key and backs it up as a seed phrase of 12 or 24 words under BIP-39: guessing a key is not realistic, stealing the backup is.
Under self-custody you hold the key yourself and a lost key is a permanent loss; under a custodial model a licensed third party holds it and the risk shifts to a counterparty. In Dubai outside the DIFC, holding client keys is a regulated activity: VARA licenses custodians and requires client assets to be held separately from the firm's own; check a custodian's licence in VARA's public register.
Why it matters when selling USDT in the UAE
An OTC desk never needs your private key, only an on-chain transfer that you sign locally in your own wallet after accepting a written quote. Any counterparty asking for the key or seed phrase "to verify the wallet" is describing theft; the patterns are listed in crypto OTC scams in Dubai. A licensed desk verifies identity documents (see the onboarding section) and pays to a pre-registered own-name bank account (see address whitelisting).
Illustrative example
You hold 750,000 USDT on a hardware wallet and accept a quote at a 0.15% spread, as of September 2026. You confirm the desk's deposit address and amount on the device screen and sign. At the 3.6725 peg, 750,000 USDT is AED 2,754,375; minus the spread, AED 2,750,243 goes out by UAEFTS to your own-name account the same business day. The key never left the device.
FAQ
Is a private key the same as a seed phrase?
Not exactly. A private key controls one address; a seed phrase is a 12 or 24-word backup from which a wallet regenerates all of its private keys. Both must be kept secret — either one gives full control of the coins.
Can an OTC desk ask for my private key?
No. A desk needs only an on-chain transfer signed in your own wallet. Any request for your key or seed phrase — from a desk, an exchange or "support" — is a theft attempt, and the correct response is to walk away.
What happens if I lose my private key?
In self-custody the loss is permanent: no one can reset the key or freeze the coins, and the balance becomes unreachable forever. That finality is the price of removing counterparty risk.
How should I store a private key for a large USDT balance?
On a hardware wallet kept offline, with the seed phrase written on paper or steel and stored in two separate secure locations. Never in email, cloud storage, a phone photo or a chat app.
Sell USDT without ever sharing your keys
IWGT is a VARA-licensed Broker-Dealer in Dubai. You sign the transfer in your own wallet; AED lands in your own account by UAEFTS the same business day. All-in spread 0.08–0.40% by size, from around 100,000 USDT.
SOURCES
- BIP-39 specification — the seed-phrase backup standard, accessed 11 September 2026.
- VARA public register — licence status check, accessed 11 September 2026.
- Central Bank of the UAE — payment systems (UAEFTS), accessed 11 September 2026.
- IWGT published pricing bands and onboarding requirements, September 2026.
This guide is informational and is not legal, tax or investment advice, nor an invitation to buy or sell any virtual asset. Rules and figures are as of September 2026 — re-check the sources before acting. Virtual assets may lose their value in full or in part and are subject to extreme volatility.