<blockquote>
  <p>only one of the keys is time-locked</p>
</blockquote>

<p>Keys aren't time-locked. Transactions are. However, Bitcoin now has an opcode for this purpose: OP_CHECKLOCKTIMEVERIFY.</p>

<p>Essentially, it forces the transaction to have a lock time further in the future than its argument, otherwise the transaction is invalid.</p>

<p>In your case, the script would look like this:</p>

<pre><code>OP_IF &lt;this pubkey can spend at any time&gt; OP_CHECKSIG OP_ELSE &lt;block number&gt; OP_CHECKLOCKTIMEVERIFY OP_DROP &lt;this pubkey must wait until block number&gt; OP_CHECKSIG OP_ENDIF
</code></pre>

<p>The spend-anytime key can redeem the transaction with</p>

<pre><code>&lt;Sig&gt; 1 &lt;above script&gt;
</code></pre>

<p>The other key can redeem with</p>

<pre><code>&lt;Sig&gt; 0 &lt;above script&gt;
</code></pre>

<p>but only after the given block number.</p>

CC BY-SA 3.0
2016-10-11T17:04:36.173Z
2016-10-11T17:12:29.950Z
2016-10-11T17:12:29.950Z
maservant
<p>No, not the way you are describing. The lock is placed on transaction outputs, not the private key(s). When the lock expires the outputs can be spent but it doesnt matter which of the M of N signatures are used, just as long as they are valid and that there are at least M of N. </p>

CC BY-SA 3.0
2016-10-09T06:28:06.540Z
Using OP_CHECKLOCKTIMEVERIFY the output being spent can require the locktime of the spending transaction to be a certain value in case one of the signers doesn't sign.
Pieter Wuille
CC BY-SA 3.0
2016-10-09T09:14:25.270Z
@PieterWuille this sounds like it achieves the same effect as the question implies, but I can't quite grasp how to do it. Could you elaborate or give an example? Thank you!
Msig2
CC BY-SA 3.0
2016-10-09T03:41:37.497Z
2016-10-09T03:41:37.497Z
m1xolyd1an
<p>Is it possible to create a 1 of 2 multi-sig address in which only one of the keys is time-locked and the other can sign any time?</p>

<multi-signature><locktime>
Is it possible to combine multi-sig and locktime?
Msig2
# Is it possible to combine multi-sig and locktime?

(Asked by: username_0 on 2016-10-08)

Is it possible to create a 1 of 2 multi-sig address in which only one of the keys is time-locked and the other can sign any time?

**Tags:** multi-signature, locktime


---

## 2 answers

### Answer by username_1 on 2016-10-11. Score: 3 | Accepted answer

> only one of the keys is time-locked

Keys aren't time-locked. Transactions are. However, Bitcoin now has an opcode for this purpose: OP\_CHECKLOCKTIMEVERIFY.

Essentially, it forces the transaction to have a lock time further in the future than its argument, otherwise the transaction is invalid.

In your case, the script would look like this:

```
OP_IF <this pubkey can spend at any time> OP_CHECKSIG OP_ELSE <block number> OP_CHECKLOCKTIMEVERIFY OP_DROP <this pubkey must wait until block number> OP_CHECKSIG OP_ENDIF

```

The spend-anytime key can redeem the transaction with

```
<Sig> 1 <above script>

```

The other key can redeem with

```
<Sig> 0 <above script>

```

but only after the given block number.


---

### Answer by username_2 on 2016-10-09. Score: 0

No, not the way you are describing. The lock is placed on transaction outputs, not the private key(s). When the lock expires the outputs can be spent but it doesnt matter which of the M of N signatures are used, just as long as they are valid and that there are at least M of N.

> **Comments:**
> **username_3**: Using OP_CHECKLOCKTIMEVERIFY the output being spent can require the locktime of the spending transaction to be a certain value in case one of the signers doesn't sign.  
> **username_0**: @username_3 this sounds like it achieves the same effect as the question implies, but I can't quite grasp how to do it. Could you elaborate or give an example? Thank you!  

---

