Writing down seed phrase: printer ink or pen ink ?

[BitcoinGirl.Club]

This sounds overly complicated.

overly complicated to me

I am interested to learn how you are handling your crypto.

Your suggested set up is better because you now have some redundancy in the system, but it still seems overly complicated to me and if it were me I would still prefer to use a 3-of-5 multi-sig set up.

I really do not want other people except my wife to know how much bitcoin I have. With the x of y multi-sig wallet I can not hide my numbers LOL

[o_e_l_e_o]

I am interested to learn how you are handling your crypto.

I have multiple back ups. My wife knows about all my back ups.

I really do not want other people except my wife to know how much bitcoin I have. With the x of y multi-sig wallet I can not hide my numbers LOL

Sure you can.

Let's take 3-of-5 as an example since that's what we've been using so far.

Back up 1: Seed A, xpub B, xpub C
Back up 2: Seed B, xpub C, xpub D
Back up 3: Seed C, xpub D, xpub E
Back up 4: Seed D, xpub E, xpub A
Back up 5: Seed E, xpub A, xpub B

Any 3 of those 5 back ups gives you 3 seeds and the other 2 xpubs, allowing you to fully recover the wallet, while preventing any person from viewing the contents of the multi-sig wallet.

[r0xy]

I feel engraving on metal is better option

[LoyceV]

I am interested to learn how you are handling your crypto.

Part of my OPSEC is not sharing the exact details. It feels better that way.

My wife knows about all my back ups.

It's one of the perks of being married

[BitcoinGirl.Club]

Part of my OPSEC is not sharing the exact details. It feels better that way.

Critical Venezuela mindset, Biden might go to you for oil and gas and reconsider sanctions from USA, I mean it's fine 😉

Let's take 3-of-5 as an example since that's what we've been using so far.

Back up 1: Seed A, xpub B, xpub C
Back up 2: Seed B, xpub C, xpub D
Back up 3: Seed C, xpub D, xpub E
Back up 4: Seed D, xpub E, xpub A
Back up 5: Seed E, xpub A, xpub B

Any 3 of those 5 back ups gives you 3 seeds and the other 2 xpubs, allowing you to fully recover the wallet, while preventing any person from viewing the contents of the multi-sig wallet.

My understanding is when you will create a 3-of-5 multi-sig, all five need to have all public master key to get the wallet created first. Or you are saying I create a 3-of-5 wallet and carefully give them the public key and public master key?

[LoyceV]

Let's take 3-of-5 as an example since that's what we've been using so far.

Back up 1: Seed A, xpub B, xpub C
Back up 2: Seed B, xpub C, xpub D
Back up 3: Seed C, xpub D, xpub E
Back up 4: Seed D, xpub E, xpub A
Back up 5: Seed E, xpub A, xpub B

Any 3 of those 5 back ups gives you 3 seeds and the other 2 xpubs, allowing you to fully recover the wallet, while preventing any person from viewing the contents of the multi-sig wallet.

My understanding is when you will create a 3-of-5 multi-sig, all five need to have all public master key to get the wallet created first.

Let's just test it

I created the following Multi-Signature Wallets in Electrum ("from 5 cosigners require 3 signatures"):
A. uphold plug victory much grunt plug convince option dizzy edge observe drastic
master public key: Zpub6xxXDnNQaCWT8QAZy9omUXxqtxFvaZyqpfaH79dZYVFZidZAnvJR7ta44V5ajdy16nr917DcWkK 9yGST24TFCTNgyxnk5uJPMEpQRVoGABk
B. scrub random route excite document walk decorate disorder raw float rubber typical
master public key: Zpub6xh6PiSGQbm4rHdk4Uzevhz1zuz5Vk8vwpPxDQvNRXbCdkDfsdPwZkdRQjxA7WfnH9t8vXL8oCF kaN3SepiPbxB2WcubPkh6TWzSmqsjfaB
C. grape thumb verify sail raven river regret view net laptop clump grocery
master public key: Zpub6xv1ZrjZp8qdrcR2NfG7ZUnnw1Ce8GH39WZ8ZWyjq1yFAnguYfvMLKjrpruu1uCCWynvR9diff3 nGWx52TdNbCp43NHTJzaGQGVybo8PN8s
D. tourist brick accuse tooth spike erode remind patch biology cheese auto dinosaur
master public key: Zpub6yATJpzSCj8ps6xGJXRjHfFotNXUCTpqz2CSQcbC5V16FDJNYp8bVmUQsV4p5yiVUWvW6r1QxfU vCXz9LbpfYcSjux1fiSsVsJNgxLDNUKL
E. dinosaur kit uphold ring region attract ill blur goose swamp noodle million
master public key: Zpub6xofxsy4oCYwkfCF2Aw8XhXW9yRVPx5kBeYHtFWjRR78mmpYUH4e8kYaG6X1StgvnRidK8UBgb5 gYjRmmgmRi4i3JzeL2vRChuSjuCAK5V3

Using the seed A and master public keys B-E, Electrum produces this address first: bc1qlcaruvdjc4em502w0pxadwrhjtrh4sd5jf7td65nctr7yhm0gfgq97ynk9

Or you are saying I create a 3-of-5 wallet and carefully give them the public key and public master key?

From my little test, I think this is correct. Anyone holding 1 out of 5 cards can help you recover funds, but doesn't know the address(es). Some combinations of 2 out of 5 cards are enough to recreate the address.

[o_e_l_e_o]

My understanding is when you will create a 3-of-5 multi-sig, all five need to have all public master key to get the wallet created first. Or you are saying I create a 3-of-5 wallet and carefully give them the public key and public master key?

If you are going to create 5 separate wallets, then yes, each wallet needs to be given the other four master public keys in addition to its own seed phrase. There is no need to actually create 5 separate wallets though. I can generate 5 seed phrase, derive the 5 master public keys, use those 5 seed phrases (or master public keys if you want a watch only wallet) to create a single wallet for my own use, and then create the 5 back ups I have specified above and hand them out to 5 friends or relatives. The friends or relatives don't need to create a wallet; they just need to hold on to the back up you give them.

[BitcoinGirl.Club]

My understanding is when you will create a 3-of-5 multi-sig, all five need to have all public master key to get the wallet created first. Or you are saying I create a 3-of-5 wallet and carefully give them the public key and public master key?

If you are going to create 5 separate wallets, then yes, each wallet needs to be given the other four master public keys in addition to its own seed phrase. There is no need to actually create 5 separate wallets though. I can generate 5 seed phrase, derive the 5 master public keys, use those 5 seed phrases (or master public keys if you want a watch only wallet) to create a single wallet for my own use, and then create the 5 back ups I have specified above and hand them out to 5 friends or relatives. The friends or relatives don't need to create a wallet; they just need to hold on to the back up you give them.

In a x - of - y wallet it's actually one wallet, isn't it? There are y set of seed and public master key. LoyceV's example is perfect to understand what I mean. We are considering that one wallet.

Anyway, the concept seems clear now. All I need is to create an x - of - y. In this case if it's 3 - of - 5 then I need 5 friends to hand out -
Friend one: Seed1, xpub2, xpub3
Friend two: Seed2, xpub3, xpub4
Friend three: Seed3, xpub4, xpub5
Friend four: Seed4, xpub5, xpub1
Friend five: Seed5, xpub1, xpub2

I see a problem here. I need all five people alive to get me the full set. If anything happen to anyone of them then I lose the wallet unless I find an alternative for each set. So I will need. Friend one (a, b), Friend two (a, b), Friend three (a, b), Friend four (a, b) and Friend five (a, b). It's involving too many people LOL. Or I messed up?

[o_e_l_e_o]

I need all five people alive to get me the full set.

No, you don't. That would be a 5-of-5. The set up you've quoted is a 3-of-5. Pick any 3 of those 5 friends, and you will have at a minimum three seed phrases and master public keys from the other two seed phrases. This gives you all you need to fully restore the wallet and spend the coins from it.

[BitcoinGirl.Club]

I need all five people alive to get me the full set.

No, you don't. That would be a 5-of-5. The set up you've quoted is a 3-of-5. Pick any 3 of those 5 friends, and you will have at a minimum three seed phrases and master public keys from the other two seed phrases. This gives you all you need to fully restore the wallet and spend the coins from it.

My understanding is I need at least three seed and all 5 xpub keys on a 3 - of - 5.

Let me pick

Friend two: Seed2, xpub3, xpub4
Friend three: Seed3, xpub4, xpub5
Friend four: Seed4, xpub5, xpub1

Am I not missing xpub2? Without it I can not restore the wallet.

The combination I need to restore the wallet is

1. Seed2: xpub 1, xpub2, xpub3, xpub4 and xpub5
2. Seed3: xpub 1, xpub2, xpub3, xpub4 and xpub5
3. Seed4: xpub 1, xpub2, xpub3, xpub4 and xpub5

Since xpub2 is missing, I can not restore the wallet.

[o_e_l_e_o]

You can derive xpub2 from seed2, which you do have. You only need the 2 xpubs from the seeds you don't have.

[BitcoinGirl.Club]

You can derive xpub2 from seed2, which you do have.

That I do not know how to do. Please drop a link about it to get some idea.

You only need the 2 xpubs from the seeds you don't have.

A bit confuse now. In a 3 - of - 5 wallet don't I need at least three cosigner and all 5 xpubs to restore the wallet. I have used 2-of-3 multi sig but did not try with 3-of-5 however my understanding is the algorithm should be similar for restoring an x-of-y wallet.

[LoyceV]

You can derive xpub2 from seed2, which you do have.

That I do not know how to do. Please drop a link about it to get some idea.

Electrum can do this: New Wallet > Multi-signature wallet > "From 5 cosigners Require 3 signatures" > "I already have a seed" > scrub random route excite document walk decorate disorder raw float rubber typical > "Here is your master public key": Zpub6xh6PiSGQbm4rHdk4Uzevhz1zuz5Vk8vwpPxDQvNRXbCdkDfsdPwZkdRQjxA7WfnH9t8vXL8oCF kaN3SepiPbxB2WcubPkh6TWzSmqsjfaB.

In a 3 - of - 5 wallet don't I need at least three cosigner and all 5 xpubs to restore the wallet.

If you have 2 xpubs and 3 seeds, you have everything you need to get 5 xpubs. Or in my example zpubs (which means it's using a native Segwit address).

[o_e_l_e_o]

That I do not know how to do. Please drop a link about it to get some idea.

Every wallet which uses seed phrases uses that seed phrase to derive your master private and public keys, and indeed, all your private and public keys. The process involves a number of hash functions to turn your seed phrase in to a seed number and then that seed number in to private keys, and then elliptic curve multiplication to turn the private keys in to public keys. You don't need to know how to do this manually (and few people do) - your wallet software will do it all for you. You give it the seed phrase, it will work out the corresponding xpub.

A bit confuse now. In a 3 - of - 5 wallet don't I need at least three cosigner and all 5 xpubs to restore the wallet.

You need the threshold number of seed phrases or master private keys, which in a 3-of-5 wallet will be three. You then need at least a master public key from the remaining shares, which will be the other two. However, for these other two shares, instead of the master public key you can use a seed phrase or master private key instead, since the wallet can derive the necessary master public keys.

[Pmalek]

You need the threshold number of seed phrases or master private keys, which in a 3-of-5 wallet will be three. You then need at least a master public key from the remaining shares, which will be the other two. However, for these other two shares, instead of the master public key you can use a seed phrase or master private key instead, since the wallet can derive the necessary master public keys.

Now you have confused me.
If I use a 3-of-5 multisig setup and I have all 5 seed phrases, will the wallet accept all those seeds or do I have to import some xpubs manually? I am asking if I am the one who need to get my hands on the xpubs or will the wallet do that itself? I know that everything is derived from the seed, but I always thought you need some xpubs as well without the wallet doing the deriving part. 

[o_e_l_e_o]

-snip-

Depends on the wallet software I guess, but most that I have used will quite happily accept five seed phrases. Even if you were to enter three seed phrases and two master public keys, the wallet would still need to derive the other three master public keys from the three seed phrases you entered in order to derive the addresses in the wallet, so no reason it couldn't derive all five master public keys from five seed phrases.

[Abdussamad]

You need the threshold number of seed phrases or master private keys, which in a 3-of-5 wallet will be three. You then need at least a master public key from the remaining shares, which will be the other two. However, for these other two shares, instead of the master public key you can use a seed phrase or master private key instead, since the wallet can derive the necessary master public keys.

Now you have confused me.
If I use a 3-of-5 multisig setup and I have all 5 seed phrases, will the wallet accept all those seeds or do I have to import some xpubs manually? I am asking if I am the one who need to get my hands on the xpubs or will the wallet do that itself? I know that everything is derived from the seed, but I always thought you need some xpubs as well without the wallet doing the deriving part. 

xpub can be derived from the seed so you don't need to store the xpub separately if you have the seed.

[SeezeFire]

saving your seed on any kind of mobile app or note on a PC/Laptop is absolutely not advisable.

I personally feel the safest is a diary, but I have had people have an opposite view on this.
but a diary is way better than a piece of paper, I'm sure you have faced the issue of finding an invoice or some paper on which you have written a phone number and now can't find it.
I keep my diary really safe so if you are that kinda person, I would suggest a diary over a piece of paper and please write using a BALL Point Pen

[LFC_Bitcoin]

Engrave it on steel & hide it in your home or something. I don’t like seed words written or printed on paper. Too many things can go wrong. You’ll need at least one copy, preferably not in the same location.

[larry_vw_1955]

piece of paper, I'm sure you have faced the issue of finding an invoice or some paper on which you have written a phone number and now can't find it.
I keep my diary really safe so if you are that kinda person, I would suggest a diary over a piece of paper and please write using a BALL Point Pen

why would a diary be any safer than a piece of paper? they made out of the same material. plus if anyone ever finds your diary, there will be no doubt that it's something to read through. because it contains personal information. private stuff.