user45908: Is it possible to make a multisig wallet that requires one of the keys specifically and any of the other ones in order to sign a transaction?
For example, let's say I have a 2-of-3 multisig that has signators A, B, and C. Can I make a multisig that requires that every transaction be signed by A specifically and then one of either of the other keys?

user137719: Yes, both of these policies achieve what you are trying to do.
thresh(2,pk(A),or(pk(B),pk(C)))
thresh(2,pk(A),thresh(1,pk(B),pk(C)))
Each of them use thresh() as defined here:

thresh(NUM,POL,POL,...): Require that NUM out of the following subpolicies are met (all combinations are assumed to be equally likely).


user26873: No, but instead you can make a 3-of-4 multisig where you hold both keys A and B, then you give key C to a family member, and D to someone else(just as an example). This way you are certain that you are involved in all transactions. I presume this is the end result you are after?

45908: <p>Is it possible to make a multisig wallet that requires one of the keys specifically and any of the other ones in order to sign a transaction?</p>

<p>For example, let's say I have a 2-of-3 multisig that has signators A, B, and C. Can I make a multisig that requires that every transaction be signed by A specifically and then one of either of the other keys?</p>
 137719: <p>Yes, both of these policies achieve what you are trying to do.</p>
<p><code>thresh(2,pk(A),or(pk(B),pk(C)))</code></p>
<p><code>thresh(2,pk(A),thresh(1,pk(B),pk(C)))</code></p>
<p>Each of them use <code>thresh()</code> as defined <a href="https://bitcoin.sipa.be/miniscript/" rel="nofollow noreferrer">here</a>:</p>
<blockquote>
<p>thresh(NUM,POL,POL,...): Require that NUM out of the following subpolicies are met (all combinations are assumed to be equally likely).</p>
</blockquote>
 26873: <p>No, but instead you can make a 3-of-4 multisig where you hold both keys A and B, then you give key C to a family member, and D to someone else(just as an example). This way you are certain that you are involved in all transactions. I presume this is the end result you are after?</p>
