Can you inherit bitcoins without the private key?

Question

Since the private key is needed to validate ownership, how does it work when you cannot access the private key?

Say X owned bitcoins and willed it to Y, but Y does not have X's private key. Say X's estate does not want to to give access to the private key or the location of the private key is untraceable.

Answer 1

Y can't spend the Bitcoins. You need the private key for an address to spend the Bitcoins from that address. There's no way around it.

Answer 2

It would be possible to use a multisignature scheme in order to will the bitcoins.

A 2 out of 3 multisignature address would be shared among three keys controlled by the bequeather X, the heir Y, and a trusted third party Z, for example the notary of X.

Any two parties of the three could move the money:

• Bequeather X could change his will with the help of Notary Z.
• After demise of X, Heir Y can access the funds with support from Notary Z.
• Bequeather X and Heir Y could access it in advance for other reasons.

As Nick has pointed out, this would have to be done before the demise of the Bequeather, otherwise access would fall to whoever ended up in control of the private key, or the bitcoins would be lost if no-one regained it.