Author

Topic: Introducing The Bitcoin Note: Physical Bitcoin that Looks and Feels Like Cash (Read 1053 times)

newbie
Activity: 16
Merit: 0
It is a perfect idea to have a physical bitcoin note, this can unify a strong world central unit of exchange wherever it is acceptable, but come to think of it, the expiration date is quite not acceptable cause once it expires it loses it value!
full member
Activity: 1092
Merit: 227
Good to see you are launching new notes in the market. Well, I’m sure note is as impressive as it sounds while reading the OP. It would have been better if you shared the pics for the same. This is close to having your CC along with you and scanning it for the contactless less point of sale. Only in the bitcoin note we have extra layer of security with multi sig.

It’s what gives bitcoin ultra high security. If you miss one piece of information from the physical coins dig then you are done, no money can be accessed literally.

Great work mate.
member
Activity: 388
Merit: 30
Reward: 10M Sheen (Approx. 5000 BNB) Bounty
Just coming across this, it is a good idea and dream to fulfill. My question is that how possible will it be to convince the government of countries who still have doubt on Cryptocurrency to accept this type currency that throws them off the pitch. If there is any thing to address in the course of this vision should be about the government.

Another point to consider is that, there is still a high level of illiteracy in the developing countries, how do you thing such people will cope with the currency and rekeying of the notes. The process of spending will post a little difficulty as rekeying is so neccessary to ownership. If one have a thousand pieces, it means they have to be rekeyed.

Lastly, does it also mean that, a currency can assume any amount depending on the key and their assigned values
legendary
Activity: 3542
Merit: 1965
Leading Crypto Sports Betting & Casino Platform
So, do you think by owning and running servers to authenticate the notes.... centralizes Bitcoin again? Is the whole idea not to have Bitcoin running on a decentralized network? I hope I understand the concept of the server in this scenario ...correctly, so feel free to correct me if I am wrong.

Also, will the centralization of the server ....not place a target on your back..for government agencies to shut you down? We all know what happened with previous people who "printed" their own money.  Huh
full member
Activity: 896
Merit: 193
web developer for hire
http://bitcoinnote.com/ redirects to https://offline.cash

They aren't active in the thread. Is this venture operated by the OP or sold on?

We believe that the result of this design achieves the goal of Bitcoin that's incredibly easy to use -- like cash -- but still preserves the important quality of self-custody. Take a look at http://bitcoinnote.com/ to learn more and reserve a spot in line for our release later this summer. Any and all feedback is appreciated and I would be happy to answer any questions.
newbie
Activity: 35
Merit: 0
@ccamrobertson

Do you have a link to the public bitcoin script?
full member
Activity: 896
Merit: 193
web developer for hire
How many people did you register on site if you're sending deliveries in August it's high ?

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First deliveries are expected late August.
newbie
Activity: 18
Merit: 42
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Cool, this is not far away.
Only thing that I am little concerned is how this paper notes will be shipped to my home address, in regular envelope or with some protection against folding, and messing up the note shape during transport.
Few times I had some bad experience with my post office deliveries, especially for international delivery or if someone noticed that paper money is being sent, if you know what I mean Wink

Rigid mailers with "Do Not Bend" stickers Smiley
legendary
Activity: 2212
Merit: 7064
First deliveries are expected late August.
Cool, this is not far away.
Only thing that I am little concerned is how this paper notes will be shipped to my home address, in regular envelope or with some protection against folding, and messing up the note shape during transport.
Few times I had some bad experience with my post office deliveries, especially for international delivery or if someone noticed that paper money is being sent, if you know what I mean Wink
newbie
Activity: 18
Merit: 42
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Is there a deadline date where the code we received will no longer work?

We don't have one, but at some point we will move onto other folks waiting on the list and there might be price changes. Let me know if you run into any issues with an expired code.

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In case that website server is not working or permanently down, that means that Bitcoin note can't complete authentication, but can they still be used without that or not?
Oh, and you forgot to say when can we expect first deliveries for ordered bitcoin notes?

There is a sliding scale. If we are temporarily down, you can "offline" verify and see that the multisig is still loaded (assuming you can get data from the chain). If we are permanently down then you need to wait until the expiration ("claim before") date printed on the note.

First deliveries are expected late August.
jr. member
Activity: 51
Merit: 1
Is it true ? I still can't believe it. How cool does this look. Will it be applicable all over the world? Truly we are going to live the life of a metaverse where there will be transparency.
legendary
Activity: 2212
Merit: 7064
Good question -- in this case the exploiter can only access the notes they have in their physical possession. So they would be able to claim the funds off a note without cutting it, but that's about it. The key material that the server holds never lets you claim funds alone -- you always need the user key which is stored on the note.
Thanks for explaining this, I guess they would need to have physical possession of note together with access to server.
In case that website server is not working or permanently down, that means that Bitcoin note can't complete authentication, but can they still be used without that or not?
Oh, and you forgot to say when can we expect first deliveries for ordered bitcoin notes?
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
Ok - that is what others and I thought as well - just wanted confirmation.

I am also running a group buy in the collectibles area

Is there a deadline date where the code we received will no longer work?
newbie
Activity: 18
Merit: 42
Quote
I could see potential problem with this statement from your website.
What would happen if someone exploits your server and make fake authentication of Bitcoin Note?

Good question -- in this case the exploiter can only access the notes they have in their physical possession. So they would be able to claim the funds off a note without cutting it, but that's about it. The key material that the server holds never lets you claim funds alone -- you always need the user key which is stored on the note.

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Now my question is this, if the notes are sold unloaded and we have to fund them upon receipt, then what is the "+.017 BTC" for?

This is only to reinforce that you need 0.018 BTC + some for mining fees (the 0.017 BTC was a typo we missed before going live) in order to load the note. The payment to us is only $49 or $499 per pack plus S&H and taxes if domestic and in certain states. If you continue through checkout you will see that only the $49 plus these other fees is charged.

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The problem I was thinking of is that the NFC chip can be defective after some time. Since many people would use this kind of bill as cold storage, is there a solution to still get the funds if the NFC chip is defective?
Also if you receive such a bill you can never know if the NFC chip was scanned by the previous owner and he can simply withdraw the money after you receive the bill.

In theory you could scan the note using another app (our open source app won't do this) to capture the user key as a backup. If you receive a note from an untrusted or unknown party and you want to keep it for a while (e.g. not cut and claim or spend like cash), then you should go through a re-key procedure so you are the only holder of the user private key.
hero member
Activity: 1036
Merit: 642
Magic
I think it is a very good idea that you can load your own personal private key to the note. The problem I was thinking of is that the NFC chip can be defective after some time. Since many people would use this kind of bill as cold storage, is there a solution to still get the funds if the NFC chip is defective?
Also if you receive such a bill you can never know if the NFC chip was scanned by the previous owner and he can simply withdraw the money after you receive the bill.
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
got my email today and I have a few questions.


The site states clearly the notes are sold unloaded and that we fund them after we receive them and that the price does not include any bitcoin.

The site also says cost is $49 per set for seral number 00101 and higher - $499 per set for serial numbers under 00100.



Now my question is this, if the notes are sold unloaded and we have to fund them upon receipt, then what is the "+.017 BTC" for?
legendary
Activity: 2212
Merit: 7064
Any feedback is appreciated, notably if anything is confusing/unclear.
I see that currently we can only reserve a spot for Bitcoin Notes, but when can we expect to see them available for purchasing and delivery?
If I remember correctly I reserved my spot back in June when you first created this topic but I didn't receive any notification yet.

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A Bitcoin Note can be authenticated by scanning it via NFC. Our server will authenticate the note using keys embedded in the NFC chip.
I could see potential problem with this statement from your website.
What would happen if someone exploits your server and make fake authentication of Bitcoin Note?
newbie
Activity: 18
Merit: 42
We've just updated our homepage with an FAQ and more details on the security model of the Bitcoin Note and I thought it would be worth adding here:


Any feedback is appreciated, notably if anything is confusing/unclear.
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
Okay, but what happens if you lost the note?
The same as any other physical item you lose: it's gone, and someone else may find it.

Something like this will certainly draw the attention of governments, because it closely resemble the "printing" of a currency. Now on the other hand, if you designed it more to resemble a "Gift card" .....it will be more acceptable to governments.
It's just barter. I can exchange my TV for your bicycle. Or for a drawing you made, for something you printed, or for some magic internet money Satoshi created. Governments can't stop you, they'll just tax you.
legendary
Activity: 3542
Merit: 1965
Leading Crypto Sports Betting & Casino Platform
Something like this will certainly draw the attention of governments, because it closely resemble the "printing" of a currency. Now on the other hand, if you designed it more to resemble a "Gift card" .....it will be more acceptable to governments.

I know the ultimate goal with true Crypto enthusiast like us, is to use Bitcoin as a "Currency" and not as a "Commodity" .....but I think this is going to create a stir.

The laws and regulations in different countries differ, so I presume the target market for this is countries where Bitcoin are allowed as "Legal tender" ......and in countries where it is not allowed ===> Collectables? (Offline Cash is a bit controversial...right?)
newbie
Activity: 3
Merit: 0
Okay, but what happens if you lost the note?
legendary
Activity: 2520
Merit: 3238
The Stone the masons rejected was the cornerstone.
  Love the idea and the designs....You should also announce in the collectables section here...plenty of people would buy once available.

  https://bitcointalk.org/index.php?board=217.0

 
legendary
Activity: 3304
Merit: 8633
icarus-cards.eu
i became aware of the new Bitcoin notes yesterday and today i created an own thread in the collectors section Wink (after i couldn't find this thread in the search function) Tongue
find the design and the concept with nfc and multisig very interesting and would like to add this to my big collection after the Polymerbit notes

have today also put me on the waiting list Grin
will there also be other editions or it remains with these 4 motifs?
sdp
sr. member
Activity: 469
Merit: 281
Please comment on my Cheap Notes concept.  I think you could integrate some ideas.  I don't think 100 µBTC or 1 mBTC bills justify a NFC chip but the two redeem periods are a concept which I think is good.

https://bitcointalksearch.org/topic/introducing-cheap-bitcoin-notes-5402081

The user still has to trust the issuer, but the same is true about centralized exchanges....
newbie
Activity: 18
Merit: 42
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That would be great to see and anything less than $100 is acceptable for this in my opinion, and this could work almost like hardware paper wallet with NFC support.
One thing I would like to see is option to somehow have anonymous purchase and shipping to PO boxes, or maybe even local purchase.

We will very likely never make a larger note unless we change the security model; but we very much do want to make smaller notes over time.

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I'm in dual minds. It isn't original but it's a nice idea keeping bitcoin notes. They look nice but trusting strangers isn't easy. Who's comfortable believing cryptocurrency coins and notes makers ?

Our hope is that our model gives you a different trust model than previous notes where the private key could note be rotated.
full member
Activity: 896
Merit: 193
web developer for hire
I'm in dual minds. It isn't original but it's a nice idea keeping bitcoin notes. They look nice but trusting strangers isn't easy. Who's comfortable believing cryptocurrency coins and notes makers ?
legendary
Activity: 2212
Merit: 7064
We don't have pricing ready just yet, but think somewhere around a set of Opendimes. Limited production runs right now mean we don't get great volume discounts, but these notes will be low serial number (if that matters).
That would be great to see and anything less than $100 is acceptable for this in my opinion, and this could work almost like hardware paper wallet with NFC support.
One thing I would like to see is option to somehow have anonymous purchase and shipping to PO boxes, or maybe even local purchase.

Thanks! The apps will implicitly authenticate the notes with us (although, of course, that's trusting us) and we're investigating making them capable of auditing the multisig independently from us. In either case we hope that open sourcing the apps means that folks have an alternative means of verifying the multisig and how the apps function if so desired.
There are other bitcoin wallets that support NFC, so it would be cool if you could support third party wallets that have multisig.


newbie
Activity: 18
Merit: 42
Quote
You're contradicting yourself. It now sounds like it it has all the drawbacks of physical storage while it still requires an on-chain transaction. And after each on-chain transaction, the remaining value will be reduced (because of transaction fees).

It depends on your trust model. If you receive a note fresh from a family member as a gift, you might not re-key. If you are going to spend the note right away, you probably won't re-key. If you plan to claim funds off the note by cutting it soon you might not re-key. There are a bunch of scenarios where you may opt not to re-key and just spend like cash. We suspect gifting from a trusted party is going to be one of the most common cases near term, hence folks won't be re-keying frequently.

Most physical storage similar to this can't be re-keyed at all. Your options are, claim right away or trust the person who gave it to you (into perpetuity or until you will claim).

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However, one big question remains: what will this "re-keying" mean.
I hoped it's something that doesn't involve re-creation of a new wallet (and new address), hence no new tx, but I don't know...

It does require sending funds to a new multisig -- we are recommending/defaulting to really low fees since given the notes are long lived it doesn't make sense that bills need to be loaded within a few blocks.
hero member
Activity: 1008
Merit: 960
My guess is that they plan to sell them unfunded, basically expecting the first owner fund it on-chain.
Yeah, these Bitcoin notes won't be sold pre-funded. It's mentioned in the OP that they will write an encrypted private key on the paper and the user will write down the user key. After that, the note gets loaded.


Since OP didn't include any pictures and no one else shared any, I though this thread should have some, so people can see what is being discussed withoout having to leave the forum. Here are a few that can be found on the official website:
~snip~

Interesting. They look very similar to Australian bills:



I guess it's because they're polymer bank notes, and that technology was invented in Australia:

Modern polymer banknotes were first developed by the Reserve Bank of Australia (RBA), Commonwealth Scientific and Industrial Research Organisation (CSIRO) and The University of Melbourne
legendary
Activity: 2730
Merit: 7065
My guess is that they plan to sell them unfunded, basically expecting the first owner fund it on-chain.
Yeah, these Bitcoin notes won't be sold pre-funded. It's mentioned in the OP that they will write an encrypted private key on the paper and the user will write down the user key. After that, the note gets loaded.


Since OP didn't include any pictures and no one else shared any, I though this thread should have some, so people can see what is being discussed withoout having to leave the forum. Here are a few that can be found on the official website:




legendary
Activity: 3668
Merit: 6382
Looking for campaign manager? Contact icopress!
It now sounds like it it has all the drawbacks of physical storage while it still requires an on-chain transaction. And after each on-chain transaction, the remaining value will be reduced (because of transaction fees).

From my understanding on-chain transaction will happen only when this notes are getting funded. Most probably only once.
My guess is that they plan to sell them unfunded, basically expecting the first owner fund it on-chain. Afterwards it can be passed on with the nominal value being contained there.

However, one big question remains: what will this "re-keying" mean.
I hoped it's something that doesn't involve re-creation of a new wallet (and new address), hence no new tx, but I don't know...
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
When you re-key the user key you are really sending from the first multisig to a new one.
As a payment instrument that you pass from person to person, on-chain transactions should be fairly minimal (unless you want to re-key the note).
If you're the last holder and you didn't re-key the note, it's probable that someone else also has a copy of the key (hence why we recommend re-keying when you receive a note).
You're contradicting yourself. It now sounds like it it has all the drawbacks of physical storage while it still requires an on-chain transaction. And after each on-chain transaction, the remaining value will be reduced (because of transaction fees).
newbie
Activity: 18
Merit: 42
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Insert Quote
I really like this project, thanks for making it.

There's a weird feeling with this one though, on one hand it looks like a great item for a collection, being a limited edition. But on the other hand, the whole purpose of it is to become more mainstream and very common, so that a lot of people are trading it back and forth, which would lower the collector's value.

I guess the first edition might keep the value as a collector's item and next batches would be not limited...

Any plans decided now about the future of production of these bills?

Thank you -- we have to start somewhere and we believe collectable -> gifting -> mainstream is the right path. The first edition will get low serial numbers as at least one point of distinction. But yes, we would really like to do some much larger production runs of bills (ideally millions).

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awesome - I would love to set up a group buy!

Great! Stay tuned for the order notification email and drop me a line when it comes through. I'm just cameron [at] offline [dot] cash
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
That's really good to know, makes complete sense. We can probably coordinate something behind the scenes if multiple folks are in line.

awesome - I would love to set up a group buy!
hero member
Activity: 1008
Merit: 960
I really like this project, thanks for making it.

There's a weird feeling with this one though, on one hand it looks like a great item for a collection, being a limited edition. But on the other hand, the whole purpose of it is to become more mainstream and very common, so that a lot of people are trading it back and forth, which would lower the collector's value.

I guess the first edition might keep the value as a collector's item and next batches would be not limited...

Any plans decided now about the future of production of these bills?
newbie
Activity: 18
Merit: 42
That's really good to know, makes complete sense. We can probably coordinate something behind the scenes if multiple folks are in line.
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
the reason I ask is there are a few of us on the forums that arrange and process group buys where many members here may partake and then have all the ordered items shipped to one location where the members then also have their various orders consolidated to reduce shipping costs.

If it was possible to know a limit on quantity and/or price, it might be possible to arrange a group buy here where it is possible that 50 or more sets could easily be ordered as one order.
newbie
Activity: 18
Merit: 42
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1. Love the design, i think they can make for great collectibles and you could release different versions later down the road.

2. Amazing concept, i think this makes for great UX. Will definitely use this to spice gifts up. Is there an easy way for non key holders to verify what’s on the bill and that it’s genuine?

3. I would add some place in the app that will explain the expiration date, just in case there’s misconceptions and people think their Bitcoin will expire.

Thanks! The apps will implicitly authenticate the notes with us (although, of course, that's trusting us) and we're investigating making them capable of auditing the multisig independently from us. In either case we hope that open sourcing the apps means that folks have an alternative means of verifying the multisig and how the apps function if so desired.

Yes, definitely -- the UX of the app is really important in helping less technical users understand the notes and their limitations.
full member
Activity: 168
Merit: 421
武士道
1. Love the design, i think they can make for great collectibles and you could release different versions later down the road.

2. Amazing concept, i think this makes for great UX. Will definitely use this to spice gifts up. Is there an easy way for non key holders to verify what’s on the bill and that it’s genuine?

3. I would add some place in the app that will explain the expiration date, just in case there’s misconceptions and people think their Bitcoin will expire.
newbie
Activity: 18
Merit: 42
We don't have pricing ready just yet, but think somewhere around a set of Opendimes. Limited production runs right now mean we don't get great volume discounts, but these notes will be low serial number (if that matters).

We probably will let folks order more than one set, but can't confirm that just yet.
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
> maybe I dont understand the answers above - but what happens on Jan 4 2029 to any of the notes should they still be loaded?

On January 3 2029 the multisig downgrades from 2-of-2 to 1-of-2 where the only key that can spend the funds is the user key on the note. If you're the last holder and you didn't re-key the note, it's probable that someone else also has a copy of the key (hence why we recommend re-keying when you receive a note).

ahh ok gotcha.

is there an estimated price for the set of 4 notes? and how many sets will each reservation be able to purchase?
newbie
Activity: 18
Merit: 42
> maybe I dont understand the answers above - but what happens on Jan 4 2029 to any of the notes should they still be loaded?

On January 3 2029 the multisig downgrades from 2-of-2 to 1-of-2 where the only key that can spend the funds is the user key on the note. If you're the last holder and you didn't re-key the note, it's probable that someone else also has a copy of the key (hence why we recommend re-keying when you receive a note).
legendary
Activity: 2254
Merit: 2419
EIN: 82-3893490
Thanks for the feedback. Expiration is indeed a weird concept here -- maybe there is a better word. On the notes it states "Claim Before Jan 3 2029" as a warning, with the goal of indicating to a holder that *something* should be done before that date if they haven't re-keyed the note.

maybe I dont understand the answers above - but what happens on Jan 4 2029 to any of the notes should they still be loaded?
newbie
Activity: 18
Merit: 42
Thanks for the feedback. Expiration is indeed a weird concept here -- maybe there is a better word. On the notes it states "Claim Before Jan 3 2029" as a warning, with the goal of indicating to a holder that *something* should be done before that date if they haven't re-keyed the note.
legendary
Activity: 2212
Merit: 7064
Yeah, this is a great question. We needed to have a condition where the multisig reverts from 2-of-2 (the user key on the note and the encrypted key on the note) to 1-of-2 in the case where we go out of business or simply refuse to release the encryption key. This happens after the expiration date. It's a bit of weird concept, but we always want to make sure you retain ultimate control over the Bitcoin.
OK, that means that I could still spend Bitcoin from my Bitcoin Note even after it is ''expired''.
Maybe you should rephrase that and add explanation it is only related with multisig, because it reminded me on CBDC that central banks are creating with expiration period, after that digital currency becomes unusable and goes back to zero.
I would also like to see more information how multisig works, but it's nice to see you are going to release code as open source.
I am going to reserve my spot, and decide later about purchase depending on price.


newbie
Activity: 18
Merit: 42
> Is this going to work with lightning? The Bold Card for example uses NFC and allows lightning transaction by just tapping it.

We designed these to be long-lived with few transactions throughout their life. We thought about Lightning but decided to start first with vanilla Bitcoin. As a payment instrument that you pass from person to person, on-chain transactions should be fairly minimal (unless you want to re-key the note). The Bold Card makes way more sense for frequent on-chain transactions, e.g. like a debit or credit card.

> Also, is there any open source app, library, or standard that can be used to confirm that the bill actually holds the funds it says it has? Of course it can have a public address, but that doesn't mean it has control over it. Not sure if it's possible to prove this. I guess something like this is critical for mass usage of this type of thing.

Given knowledge of the redeem script and the public keys which are plaintext on the note you should be able verify the address.
hero member
Activity: 1008
Merit: 960
Is this going to work with lightning? The Bold Card for example uses NFC and allows lightning transaction by just tapping it.

Also, is there any open source app, library, or standard that can be used to confirm that the bill actually holds the funds it says it has? Of course it can have a public address, but that doesn't mean it has control over it. Not sure if it's possible to prove this. I guess something like this is critical for mass usage of this type of thing.

And finally, why are you guys patenting this?, it feels very far from the original idea of Bitcoin and the open source philosophy.
newbie
Activity: 18
Merit: 42
> How exactly does your chip change the multisig configuration when the expiration date is reached?

The script is created from a template when the first user loads the note; we are using OP_CHECKLOCKTIMEVERIFY to modify the conditions of the multisig from 2-of-2 to 1-of-2 in 2029. When you re-key the user key you are really sending from the first multisig to a new one. We're going to release the script for review prior to note shipment as well as have a more detailed article on security.

> Will you open source / peer review your technology?

The script and mobile app will both be fully open sourced for review.

> Will these items get redeemed only after expiration or by destroying them?

Exactly; those are the only two conditions where you can redeem. "Cutting" doesn't require slicing the whole note in half, only a portion of it.
legendary
Activity: 3668
Merit: 6382
Looking for campaign manager? Contact icopress!
We only release the decryption key when someone cuts the note and reports this via an authenticated and encrypted way to our server

I see this as yet another nice collectible, especially by changing the PK it should be safer than the established collectible items.
My questions are:
* Will you open source / peer review your technology? I mean that nothing stops you have something else than you claim (i.e. you can keep private keys, maybe make it 2-of-3 with 2 keys in your hands, and redeem yourself the funds after a couple of years).
* Will these items get redeemed only after expiration or by destroying them? I mean that usually collectibles do have a value even if they are redeemed (if they are not destroyed).
legendary
Activity: 1568
Merit: 6660
bitcoincleanup.com / bitmixlist.org
> What I don't understand is that each note has an expiration date, so does this mean that bitcoin can't be used or what?

Yeah, this is a great question. We needed to have a condition where the multisig reverts from 2-of-2 (the user key on the note and the encrypted key on the note) to 1-of-2 in the case where we go out of business or simply refuse to release the encryption key. This happens after the expiration date. It's a bit of weird concept, but we always want to make sure you retain ultimate control over the Bitcoin.

How exactly does your chip change the multisig configuration when the expiration date is reached?

I'm assuming that the unlocking script is already etched inside the NFC as 2-of-2 multisig (user-key and your own key).

This raises two situations where the unlocking script would have to be updated:

- You want to change your own plaintext PK
- (as I mentioned) the expiration date renders your key unnecessary.

From my understanding, you can't simply create a new unlocking script for the bitcoin without knowledge of the private key. You would need to have the expiration date check coded inside the unlocking script (I'm not sure if this is even possible), but it doesn't explain the other scenario, how can you change the user key and modify the multisig unlocking script to use the new key?
newbie
Activity: 18
Merit: 42
> What I don't understand is that each note has an expiration date, so does this mean that bitcoin can't be used or what?

Yeah, this is a great question. We needed to have a condition where the multisig reverts from 2-of-2 (the user key on the note and the encrypted key on the note) to 1-of-2 in the case where we go out of business or simply refuse to release the encryption key. This happens after the expiration date. It's a bit of weird concept, but we always want to make sure you retain ultimate control over the Bitcoin.
legendary
Activity: 2212
Merit: 7064
The Bitcoin Note is a cash instrument that is backed by Bitcoin via multisig. Each note is printed with beautiful, currency-grade elements that use secure printing techniques typically reserved for government documents like microtext, raised print and foil. More importantly, each note includes a secure NFC chip which is where a multisig lives that allows you to claim the Bitcoin at any time.
This bitcoin note looks great and I think it has potential to be very valuable collectibles item if there is limited number of first edition paper notes.
I have seen similar products before but I think this is the first product  that is offering multisig solution with locally encrypted key.
What I don't understand is that each note has an expiration date, so does this mean that bitcoin can't be used or what?
newbie
Activity: 18
Merit: 42
Hello --

Excited to show off something that we've been working on: the Bitcoin Note. The Bitcoin Note is a cash instrument that is backed by Bitcoin via multisig. Each note is printed with beautiful, currency-grade elements that use secure printing techniques typically reserved for government documents like microtext, raised print and foil. More importantly, each note includes a secure NFC chip which is where a multisig lives that allows you to claim the Bitcoin at any time.

We were heavily inspired by OG Bitcoin physical money like Casascius coins, however, we wanted to created a design whereby (1) anyone can spend, gift and share the Bitcoin for years to come without having to worry a sophisticated attacker who extracts a private key from under a label or scratch off and (2) trust was minimized on that part of the printer (us).

This lead us to the design we landed on for the Bitcoin Note --

  • An NFC chip readable by nearly all modern smartphones
  • A two part multisig where (1) we write an encrypted private key to the note (and don't keep a copy and (2) you write a user key to the note in plaintext and then load the note
  • We only release the decryption key when someone cuts the note and reports this via an authenticated and encrypted way to our server
  • The multisig reverts to only your key after a printed expiration date on the note
  • You can re-key the user key on the note you receive if you want to hold it for a long time

The result is you do not need to trust us as the creators of the note. While, as I noted, we do not keep a copy of the encrypted private key this doesn't really matter: by the construction of the multisig, this key can never access the funds alone. Likewise, the expiration date means that even if we aren't around or refuse to allow for the claiming of a note by cutting it, the holder can wait and then use the user private key to claim.

We believe that the result of this design achieves the goal of Bitcoin that's incredibly easy to use -- like cash -- but still preserves the important quality of self-custody. Take a look at http://bitcoinnote.com/ to learn more and reserve a spot in line for our release later this summer. Any and all feedback is appreciated and I would be happy to answer any questions.
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