At some point I expect some court to say "X shares were illegally transferred from person A, give them back". If we don't know where they went, it's impossible on block-chain to give them back, unless we assume the existence of someone who has the rights to make arbitrary changes, at which point there is no point having a blockchain.
But I think really the statement of interest is here: > ... at which point there is no point having a blockchain.
Lots of people have different reasons for liking block chains. Their reasons may disagree with yours.
And what if they refuse [despite consequences]?
> Lots of people have different reasons for liking block chains. Their reasons may disagree with yours.
I'd say the common/paramount feature is "decentralized, trustless ledger w/distributed consensus." Dillinger talks at length here about how "...the Trustless nature of Bitcoin was the main thing that convinced me Satoshi wasn't scamming." Yes, lots of private things calling themselves a "blockchain" exist. But those all submit themselves to some sort of authority/trust system. And it's likely the case that they do that in order to avoid the problem described.
IMO it's anarchy [good connotation] vs rule-of-law. Crypto-coin/asset systems can be ruled by distributed consensus but this feature is mutually exclusive with state-managed systems. When they intersect or when they're forced to intersect, we end up with an imbalance/mismatch.
I feel like this is a problem that is pretty commonly exercised in our legal system and incarceration is usually a strong last resort motivator.
This is just the tip of the iceberg BTW. What if they die or have a brain injury? Their password securing the wallet is now lost to the world. Now there's no way to reverse this transaction. We accept this risk with the trustless system of currency. But real estate, equities, this kinda stuff -- it just doesn't map well at all.
One other potential problem is that if an owner of some Bitcoin dies, there may not be access to their wallet at all. However, if there is considerable wealth in that wallet, they should have incentive to pass that on to their heirs, in which case they may have set up a will or otherwise passed on instructions for how to recover the money. Whoever that money is recovered to can then be approached for settling the estate or what-have-you.
In the end, though, laws and the consequences for breaking them are (in principle) set up to incentivize behavior that is good for society. If you break laws, you face consequences. If you avoid those (e.g. court orders you to pay and you refuse), you face other/worse consequences (e.g. garnished wages, contempt of court). If the consequences still aren't strong enough or enforceable enough to maintain the peace, then society has a problem and new laws can be passed.
The problem is using blockchains to represent shares in a company (for example). Ownership of a company can't be "lost", or "unpaid". Legally, someone owns each share of a company, and a court can declare ownership is moved. At that point, your blockchain doesn't represent reality any more (as declared by a court) and then, what value does it have?
Can a court actually declare that ownership is moved, or can they only declare that one is to transfer ownership, implicitly under penalty of something else if you don't? If you have a car and the court declares that it is my car now, that doesn't physically transport it to my driveway and you could steps to prevent that from happening (eg, driving it into a lake).
When it comes to things like houses, a court certainly can declare ownership is changed, there is no option for you to refuse, or have to do anything.
This already happens without block chains.
Can that be abused? Yes. But all such abuse will be evident in the public record, and then the usual legal system can easily get involved -- which it already did anyway, if you're doing a proper IPO just with stocks tracked on a "block chain".
And how do you think theft of stock certificates is handled (they are a piece of paper)? Stock certificates do satisfy legal requirements...
For example, when someone on Twitter raised the problem of collaterizing smart contracts (no one is going to lock capital away in extended escrow, which creates an obvious enforceability problem), Naval Ravikant argued in response that a third party guarantor would be necessary. As far as I can tell, he didn't recognize the irony in his own statement.
I only follow blockchain/ICO events from the peripheries so I'm sorry if I'm grossly misunderstanding.
Would you ever trust some random, small-time agent to collaterize a smart contract you're involved in? That's obviously foolish. Even trusting a mid-size agent is foolish. You don't know how these people are operating, and whether they might go insolvent the very next day. This is one of the primary reasons we have large, regulated, centralized institutions in the first place.