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Re:Finality does not exist in payments by janandonly on Tuesday February 15, 2022 @02:30PM (#30351440)
There is a misleading, or more correctly put, wrong, statement here about bitcoin transactions not being final.

They are final.

https://bitcoin.stackexchange.com/questions/88289/what-is-tr...

Re:Finality does not exist in payments by tsatsawayy on Tuesday February 15, 2022 @02:39PM (#30351547)
I think that's the point that the author is trying to make. If the federal government disagrees with the bitcoin blockchain, then the blockchain is wrong.

It doesn't really matter what the code says, or what bits are inscribed somewhere. Finance and ownership are ultimately enforced by armies, not computer programs.

This is one reason why some people think that cryptocurrencies are playing with fire. It's also why major exchanges won't make it easy to cash out laundered bitcoins to USD.

Re:Finality does not exist in payments by outworlder on Tuesday February 15, 2022 @03:05PM (#30351894)
Yes, but even the federal government has no power to move the -original amount- if you throw away the key.

They can make you cough up an equivalent amount in fines, of course. But the original amount is gone.

Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @03:38PM (#30352338)
You can make the same point about cash, but it's not very interesting.

The point the article was making is that transactions can and will be deemed illegitimate, both in the sense that mistakes are made, and in the sense that the legal framework will decide you have to reverse the payment. If you've buried cash and refuse to tell people where it is, you are in roughly the same place as refusing to reveal keys. You can be held accountable of course, in various ways.

I think the article was more making the point that any payment system that doesn't recognize this reality will have inherently limited uptake, which is probably true.

Re:Finality does not exist in payments by yanmaani on Tuesday February 15, 2022 @03:56PM (#30352594)
It's true for cash, but not for cards. If a merchant incorrectly gets my $1000, and I charge him back, I will get my money, even if he spent $1000 on coke and hookers.
Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @04:08PM (#30352745)
You'll get different cash back, sure. Which was sort of the point; it's part of what makes CC useful.

I was noting that there is nothing fundamentally different between say you accepting a payment in bitcoin and refusing to cough up the key when told to reverse it, or accepting a payment in cash and burying it then refusing to tell police where.

Fundamentally there are mechanisms to reverse this, or punish/constrain you for obstructing the process. Some payment systems have them built in at a very low level (CC chargebacks), some rely on professional standard (hold harmelss), etc. Some rely on court systems. That's a trade off of convenience vs. risk, but doesn't change the fundamental point that a payment system without a standard reversal mechanism is going to have limited use.

Re:Finality does not exist in payments by yanmaani on Tuesday February 15, 2022 @04:19PM (#30352873)
> There is nothing fundamentally different between say ... bitcoin ... and ... cash ...

Agreed.

> That's a trade off of convenience vs. risk, but doesn't change the fundamentals.

There is. The ones that rely on court mechanisms aren't the payment mechanism being reversible, it's something else (the storage) that gives first.

It's true that if you keep it in your bank account, all transactions are reversible. But that's a statement about property rights, not about finality. If I have a solid means of "storing" my money, such as by burying it in my back yard, then the payment itself is irreversible. That's not true for cards, which are reversible even if your storage is 100% robust.

Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @04:24PM (#30352944)
> the payment mechanism being reversible, it's something else (the storage) that gives

I'm not sure we agree on this being fundamental. At least you can define it as a categorical difference (sure) but not really a practical difference.

I think the articles points were twofold: 1) Property rights, or more generally the legal & regulatory systems, trump any rules imposed or agreed in your system of payments 2) Most payments systems feature reversal processes for necessary reasons (but if they don't, see (1) as fallback position)

Both of these seem important to understand if you want to understand how a payment system works or could work in the future, and also to understand your exposure/risk in using them.

People mostly understand the trade offs and limitations of cash; mostly probably don't understand them well for lots of payment systems.

Re:Finality does not exist in payments by yanmaani on Tuesday February 15, 2022 @04:44PM (#30353194)
I don't think the first point is accurate. You have to study the entire system, which is made up of two parts:

1. Storage

2. Payment rail

If your storage is solid (e.g. keys in brain wallet, account in crooked bank, money in shoebox) and the payment rail is solid (e.g. gold, cryptocurrency, cash), you're good. (To clarify, "solid" here means "beyond the legal-regulatory system", which means the rules aren't trumped.) Otherwise, you aren't.

I say that Bitcoin has "finality," because it does the job of payment rail with 100% irreversibility.

Grant that Bitcoin is a mediocre storage (1). But the payment rail (2) truly is irreversible. The combined system of two disjoint parts, built out of bitcoin-as-storage and bitcoin-as-payment-rail, is not.

Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @05:01PM (#30353412)
> "beyond the legal-regulatory system",

I think it is a mistake to believe this is a thing. You can be allowed to operate in gray areas for a bunch of reasons, or you can be small enough not to be too bothered about (e.g. shutting you down not deemed worth the effort); but this is a choice of those same systems, not in your control really.

Although to be fair, I guess this stuff really varies by jurisdiction. Otoh, where the gray areas get bigger, your chances of having that go against you are bigger also.

Re:Finality does not exist in payments by yanmaani on Tuesday February 15, 2022 @05:14PM (#30353574)
It's certainly a thing for the payment rail - Bitcoin qua payment rail is entirely irreversible. So as a category in the real world, it is trivially a thing.

Whether such storage exists is a much better question. I think it depends on what you want to do with it. For example, if the Bitfinex guys were ideologically motivated, they could've spent all the money on, I don't know, political ads or whatever. More generally, I think you can certainly come up with storage that is outside the reach of a given threat actor in pursuit of a given goal.

Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @05:35PM (#30353811)
> > So as a category in the real world, it is trivially a thing.

I'm not saying bitcoin isn't a thing in the world; I was saying that I don't think that makes it "beyond the legal-regulatory system", or that that is really even a helpful/useful concept. I mean we can talk about various shadow economies, but they are just that - and not really in scope for OP article.

Re:Finality does not exist in payments by beaned on Tuesday February 15, 2022 @02:50PM (#30351707)
> If the federal government disagrees with the bitcoin blockchain, then the blockchain is wrong

It isn't, though. The record is kept, and in fact the government needs to submit to the blockchain's laws to move any coin around.

Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @03:11PM (#30351974)
> The record is kept

It is kept in the same sense that you can draft a contract declaring you the owner and supreme ruler of the moon.

> in fact the government needs to submit to the blockchain's laws to move any coin around

No, it's the opposite: Everybody moving around coins has to submit to applicable laws – or face the consequences of violating them.

Re:Finality does not exist in payments by beaned on Tuesday February 15, 2022 @04:24PM (#30352942)
I don't think you understand how the Blockchain works or what the proper concept of a finalized payment is.

The government cannot undo a Bitcoin transaction. If the keys are accessible, they can seize the coin and create a new transaction to redistribute according to the law.

If the keys are not accessible, then they are totally powerless to do anything at all.

The government submits to the blockchain's rules the same way everyone else does. That's kind of the point.

Re:Finality does not exist in payments by vageli on Tuesday February 15, 2022 @05:00PM (#30353395)
This becomes obvious when you consider that the government auctions the coins they seize. They either have to give the keys to the buyer or create a new transaction on the chain.

The interesting thing in this whole conversation is assuming the person holding the key is the custodian of the funds, when it is more the key itself that is the custodian. The keys hold the funds, the person holding the keys can change but that is entirely outside the system but so is getting robbed on the side of the street of the cash in your pocket.

Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @05:09PM (#30353515)
> If the keys are not accessible, then they are totally powerless to do anything at all.

If you truly believe that, I don't think you understand how law enforcement works.

Re:Finality does not exist in payments by beaned on Tuesday February 15, 2022 @06:45PM (#30354534)
I think you need to elaborate on this. Law enforcement can enforce the things they have power over, like putting someone in jail. But they do not have power over the blockchain and they cannot reverse a transaction.
Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @07:39PM (#30354967)
Governments can put a blockchain account/UTXO on a sanctions list and make it a crime to accept payments directly or indirectly funded from that account.

To my knowledge, this hasn't happened yet, but I strongly suspect that it's only a question of time. Embargoes/sanction lists are one of the most powerful mechanisms of law enforcement for governments – I doubt that they will continue to let cryptocurrencies undermine that for too long.

Re:Finality does not exist in payments by beaned on Tuesday February 15, 2022 @07:50PM (#30355054)
It's a tool, but not a silver bullet. Mixers exist, for example. But that's not even the main point. The key holder has the ultimate power to simply throw away the key. There is no recourse for that.
Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @09:47PM (#30355792)
> It's a tool, but not a silver bullet. Mixers exist, for example.

Definitely, but I don't think that mixers would be considered an acceptable "excuse" for dubious coin origin.

> The key holder has the ultimate power to simply throw away the key. There is no recourse for that.

True, but what is the utility of that?

Re:Finality does not exist in payments by beaned on Friday February 18, 2022 @07:50PM (#30393319)
Not talking about coin origin are we.

I suppose the point is to not have something seized from you which you do not want taken.

Anyway, these questions are now outside of/unrelated to common sense understanding of what a "finalized" payment is.

Re:Finality does not exist in payments by panqueque on Tuesday February 15, 2022 @06:32PM (#30354422)
What do you think a government would do if the private key was forgotten and not backed up?
Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @07:42PM (#30354990)
The same thing it would do if stolen physical cash turns out to have burned up in a fire or lost at the bottom of the ocean.
Re:Finality does not exist in payments by panqueque on Tuesday February 15, 2022 @06:46PM (#30354544)
Yeah, there's a certain irony to the fact that crypto currencies will remain subordinate to the powers that be until they themselves become the powers that be (at which point, of course, any elements of crypto-anarchy and cypherpunk would be long gone).
Re:Finality does not exist in payments by topher200 on Tuesday February 15, 2022 @02:39PM (#30351562)
From the beginning of TFA:

> An extreme example which proves the point: the cryptocurrency enthusiast community largely believes that code is law, “not your keys, not your coins”, etc. Many crypto enthusiasts would say that the Bitcoin protocol does not prohibit reversing transactions but provides a security guarantee which suggests that the likelihood of a reversal after an hour is infinitesimal.

> And yet: someone sent $70 million worth of Bitcoin in 2016, and that transaction was partially voided, with the reversal being worth slightly more than $70 million due to Bitcoin volatility. This didn’t happen an hour later; it happened in 2022. How?

> The answer is nowhere in the Bitcoin whitepaper or any codebase. A full recounting of it is outside the scope of this anecdote, but it rhymes with “If you and the United States federal government disagree whether a transaction is final, you are wrong.” That is true for notorious Bitcoin thefts, but also true for wire transfers, conveyances of real estate, credit card payments, and graverobbing. “Possession is nine-tenths of the law,” so the saying goes, but the state can conjure as many tenths as required if it is motivated to.

Re:Finality does not exist in payments by DennisP on Tuesday February 15, 2022 @02:45PM (#30351641)
"How" is easy: they were storing their private key in an online account and the government found it. Nothing in Bitcoin was reversed. The government confiscated their funds in the same way that criminals steal any other bitcoins with poorly-secured keys.

Just follow the link in the TFA if you want to verify that.

Re:Finality does not exist in payments by jonas21 on Tuesday February 15, 2022 @02:58PM (#30351814)
That's exactly the point. If you define the universe to include only Bitcoin, then yes, transactions are final. But if you define the universe to include the real world, then the answer is no, not really -- governments will almost always find a way to reverse the transaction, whether it's seizing your private key, or holding you in contempt of court until you divulge it.
Re:Finality does not exist in payments by tshaddox on Tuesday February 15, 2022 @03:13PM (#30352005)
The transaction was final though, in the real world. The fact that the government can physically find your private key (or physically compel you to give it to them) and use it to make new transactions is irrelevant. All you're pointing out is that after you receive money in a transaction you can later participate in a different transaction using that same money.
Re:Finality does not exist in payments by wewtyflakes on Tuesday February 15, 2022 @05:56PM (#30354044)
To the entity holding the coins, whether it is a single Bitcoin transaction as per the protocol of Bitcoin, or multiple transactions, makes no difference... ultimately they will or wont be holding a certain number of Bitcoins. To then say, "well technically that was _two_ transactions" seems irrelevant, since to the entity (no longer) holding the coins, things have been effectively reversed. I think may just be highlighting a disconnect between the writer of the article using the term transaction as understood by a layperson, and people who want to use the term transaction as per specific meaning of a particular protocol.
Re:Finality does not exist in payments by tshaddox on Tuesday February 15, 2022 @06:48PM (#30354570)
> To the entity holding the coins, whether it is a single Bitcoin transaction as per the protocol of Bitcoin, or multiple transactions, makes no difference... ultimately they will or wont be holding a certain number of Bitcoins.

But to the entity who received the coins, it also doesn't matter where the coins went after someone took them by force. If you get paid for a day's work in cash and a robber steals it on your way home, you wouldn't say that your work payment transaction was reversed or that it hadn't been finalized up to the point of the robbery.

Re:Finality does not exist in payments by wewtyflakes on Tuesday February 15, 2022 @07:10PM (#30354746)
I think that example breaks down for the laymen understanding of a transaction, since the robber is a different party than who gave the coins in the first place.

What if an employer paid you in coins, so you take your coins and go home, then tomorrow your employer decides to take back the coins they gave you since they were not happy with your work (or they're just jerks)? I think that would fit the layman understanding of "this was undone!" (i.e. the transaction wasn't final). If in this case, the underlying financial engines used two, none, or one transaction (as specifically defined by that engine), probably wouldn't matter to the one who no longer has their coins.

Re:Finality does not exist in payments by tshaddox on Tuesday February 15, 2022 @07:50PM (#30355060)
> I think that example breaks down for the laymen understanding of a transaction, since the robber is a different party than who gave the coins in the first place.

The government is certainly a different party that wasn't involved in the original transaction, right?

> What if an employer paid you in coins, so you take your coins and go home, then tomorrow your employer decides to take back the coins they gave you since they were not happy with your work (or they're just jerks)?

This can definitely happen, at least with checking accounts. It has happened to me once because an employer accidentally double-paid everyone, and they were able to withdraw one of the payments from our accounts. I'm not sure exactly how that works. It could just be that your employer essentially has full access to your checking account since you gave them your account and routing number. Incidentally, I was always curious what would have happened if I had moved everything out of my checking account before they make the correction. But regardless of how it is actually implemented in the banking system, it's pretty clear if your employer erroneously removed funds from your bank account, or if you cashed out the accidental second payment then quit your job, it would again just come down to the legal system.

Re:Finality does not exist in payments by DennisP on Tuesday February 15, 2022 @09:23PM (#30355633)
Your example with the employer is not possible with Bitcoin, unless for some crazy reason you share your private key with them.
Re:Finality does not exist in payments by repomies69 on Tuesday February 15, 2022 @03:08PM (#30351928)
It is not "reversing the transaction", it is just seizure. If you have spent the Bitcoin on a lamborghini, government will confiscate the lambo. Criminals however typically spend the stolen money on hookers and drugs. Seizure or confiscation has nothing to do with "reversing the transaction", calling it that is just stupid, mixing terms unnecessarily is just unnecessary and confusing here.
Re:Finality does not exist in payments by robot_no_419 on Tuesday February 15, 2022 @08:09PM (#30355180)
If you make a Bitcoin address, memorize the private key, and never write it down ever, then the only way for anyone to "reverse" transactions is to force you to physically say or write down the private key. This transaction finality seems to be orders of magnitude more final than a credit card transaction or a bank transaction.

So sure - it's technically reversible. But is this really a practical argument? It's like saying nobody is safe in public because you can be a victim of a terrorist attack any any moment. It's alarmist and practically wrong even if technically true.

Re:Finality does not exist in payments by Qworg on Tuesday February 15, 2022 @02:34PM (#30351492)
If you saw the "technosociolegal" position at the top, you'd appreciate a broader perspective.

Why is the couple who held the bitcoin from the hack being prosecuted? How were those funds being unwound if the transaction is final? If all of the exchanges were to denylist coins from a hack, do they actually exist or have they been taken away?

Re:Finality does not exist in payments by DennisP on Tuesday February 15, 2022 @02:42PM (#30351601)
Nothing was "unwound." The government found the criminals' private key, which they were unwisely storing in an online account. That allowed the government to make a new transaction, moving the funds wherever they liked. From the link in the article:

> special agents obtained access to files within an online account controlled by Lichtenstein. Those files contained the private keys required to access the digital wallet that directly received the funds stolen from Bitfinex

https://www.justice.gov/opa/pr/two-arrested-alleged-conspira...

Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @02:48PM (#30351669)
> Nothing was "unwound." The government found the criminals' private key, which they were unwisely storing in an online account. That allowed the government to make a new transaction, moving the funds wherever they liked.

This is how "unwinding" works in almost all payment systems: Creating a second transaction to (partially or fully) offset the effects of the original one.

Re:Finality does not exist in payments by tshaddox on Tuesday February 15, 2022 @03:16PM (#30352037)
Yes, this is how normal everyday commerce works. My employer transfers some USD into my bank account. I then transfer some of those USD to my landlord's bank account. This is in no sense a reversal of an earlier transaction or an indication that an earlier transaction was "not finalized."
Re:Finality does not exist in payments by DennisP on Tuesday February 15, 2022 @02:53PM (#30351746)
Fine, but the government has no special power over Bitcoin in this regard. If they hadn't found the key, they wouldn't have been able to issue that transaction, and any common thief who found the key could have done what they did.
Re:Finality does not exist in payments by lxgr on Tuesday February 15, 2022 @02:57PM (#30351803)
The relevant meta-point here is that the government is uniquely positioned to come into possession of most keys that it wants (or more indirectly, render them useless by including them on sanction/embargo lists).
Re:Finality does not exist in payments by Qworg on Tuesday February 15, 2022 @02:58PM (#30351818)
Yes. In a narrow technological definition of "final", you're right. However, not in the societal or legal sense.
Re:Finality does not exist in payments by woah on Tuesday February 15, 2022 @03:10PM (#30351954)
The definition of finality used by you and the author of the piece is so vague and all-encompassing as to be meaningless. There isn't really anything to debate other than semantics.

You could just as easily say that cash payments aren't final because you could lose your wallet after you put the cash in it, but using the example of Bitcoin and the federal government is going to get more clicks.

Re:Finality does not exist in payments by ska on Tuesday February 15, 2022 @03:40PM (#30352379)
> There isn't really anything to debate other than semantics.

Wasn't the point that a certain amount of ambiguity around finality is the usual (and natural) state of payment systems?

Re:Finality does not exist in payments by zaphar on Tuesday February 15, 2022 @02:49PM (#30351700)
Yeah, So the federal government unwound the transaction whether they wanted it unwound or not. Which is in fact how it works in banking institutions too. A reverse of the transaction is issued that in effect unwinds it. In the real world sense which is the context of the article the transaction has been unwound or reversed.
Re:Finality does not exist in payments by kobieyc on Tuesday February 15, 2022 @02:31PM (#30351453)
Yeah, major wtf by this author. Clearly didn't do their homework.
Re:Finality does not exist in payments by zaphar on Tuesday February 15, 2022 @02:46PM (#30351655)
There has been at least one fork that reversed bitcoin transactions. They are in no way final in practice even if the "spec" claims that they are.
Re:Finality does not exist in payments by int_19h on Tuesday February 15, 2022 @06:22PM (#30354319)
The resulting fork isn't Bitcoin, though, so no Bitcoin transactions are reversed in this manner.
Re:Finality does not exist in payments by zaphar on Wednesday February 16, 2022 @08:44AM (#30359810)
Actually the non-bitcoin fork is the one that didn't reverse the transactions. Bitcoin proper is the one that did reverse them if memory serves. I'll grant that sometimes memory does not serve though and I'm just too lazy to grab the citation right now.
Re:Finality does not exist in payments by smitop on Wednesday February 16, 2022 @05:16PM (#30366548)
I think you're thinking about this incident? https://en.bitcoin.it/wiki/Value_overflow_incident

In that case, ~9 hours of transaction history were reversed because of a transaction that resulted in an overflow in the main (and I think only at the time) Bitcoin client allowing the creation of unlimited Bitcoin.