Multisig

Every wallet so far shares one fatal flaw: a single key, or a single seed, is a single point of failure. Lose it and you’re locked out forever; let someone steal it and you’re robbed. Multisig is how you remove that single point.

Several keys, one transaction

A multisignature — “multisig” — wallet requires several keys to authorise a payment, say 2 of 3. No single key can move the funds on its own. Keep the three keys in three different places — home, work, a relative’s house — and a thief who finds one gets nothing, while losing any one of them doesn’t lock you out. You’ve turned “one key = total risk” into “no single mishap is fatal.”

Try it. Pick an M-of-N policy, then tap the keys you currently hold — the vault opens only when enough are present.

Tap a key to add or remove it.

Who uses it, and why

Individuals securing real savings use it. Families use it for inheritance — your key, an heir’s key, and a lawyer’s or a service’s key, so your coins can pass on without any one person ever having full control while you’re alive. Companies use it to require two officers to approve a spend. Some people use “collaborative custody” services that hold one key of the group as a backup and co-signer. It is institution-grade security that you can run yourself, for free.

Notice what a 2-of-3 rule really is: a small program running on the money itself, deciding the conditions under which it can move. That hints at something much bigger — Bitcoin can be programmed. Next.

Key takeaways

• Multisig requires several keys (e.g. 2 of 3) to spend, so no single lost or stolen key is fatal.
• It’s used for serious savings, inheritance, and company treasuries — institution-grade security you run yourself.

Check yourself

What does a 2-of-3 multisig wallet require to spend?

Any one keyAt least two of the three keysAll three keysA password

Why use multisig for large holdings?

It’s fasterA thief with one key gets nothing, and losing one key doesn’t lock you outIt’s cheaperIt hides the balance