reply on: Ask SN: How to sign multisig tx virtually \ stacker news ~bitcoin

474 sats \ 1 reply \ @ek 14 Jun 2023 \ on: Ask SN: How to sign multisig tx virtually bitcoin

I'm looking to setup a multisig wallet and wanted to have someone I trust be one of the signers, that way if I die or I loose a key they can help recovery funds.

So you are going for a 2of3 multisig where they can recover one key after you die or help you recover your funds if you lose one key?

Is there a way to have them sign the PSBT virtually? So far I think the best way would be to start a video call with them and have them scan the QR code / show their QR code to sign the tx but I'm not 100% sure how that would even work.

I think it's not clear to me what you are trying to do. Which transaction do you want them to sign? If you have a 2of3 multisig, you don't need them to sign any tx since you have two keys. If you lose one key, you can just tell them to give you their key so you can setup a new multisig.

And if you are dead, you can't do a video call anymore.

So I assume you are talking about the case where you lost one key and then want to do a video call with them, right?

Showing them a QR code of the PSBT over a video call should work.

Even if they were using Sparrow I'm not sure how they would actually just sign the tx since they didn't initiate the tx; would I have to send them the sparrow wallet file?

No, you need to export the partially signed bitcoin transaction (PSBT) from Sparrow and send this file to them. They can then import it into whatever software they are using and sign it.

This works since every signer needs to know the pubkey of every other cosigner.

10 sats \ 0 replies \ @021da48107 OP 14 Jun 2023

So you are going for a 2of3 multisig where they can recover one key after you die or help you recover your funds if you lose one key?

Correct

No, you need to export the partially signed bitcoin transaction (PSBT) from Sparrow and send this file to them. They can then import it into whatever software they are using and sign it.

Ah okay I think this answers my question. In the event that I lost a key I could create a tx with my remaining key, sign it and then send the PSBT to my remote cosigner. They would just import the PSBT and sign it.

I set this up as a test and for some reason my ledger hardware wallet doesn't seem to be able to sign the PSBT, not sure why, might have something to do with the deviation path being incorrect. Initially I setup the deviation path and tpub in sparrow from what I found in ledger live. However I noticed that the deviation path in ledger live and sparrow are different.