The above phrase is the title of the note at http://sclbc.zehuti.co.uk/site.aspx?i=ed47875. I guess what the authors meant was who owns "bitcoins" while they also rightly point out relevance to other blockchain-based assets. It is nice to see this and other writings appearing in the course of last year which deal with the issues I have been discussing in this blog since 2015.
The note acknowledges that questions of choice of law could arise (See my previous post), it only examines English law. It does not diminish the value of the note in view of the preeminence of English law in the practice of international commercial transactions. Any global standard which might emerge in the future might indeed mirror the framework of English law.
What should attract the attention of civil law lawyers is the meaning of "ownership." The note explains that English law recognises that there can be multiple individuals each entitled to assert 'ownership' rights to the same property. The note further casts doubt on the availability of a proprietary restitutionary claim, a cause of action which seems to come closest to rei vindicatio in the civil law legal systems.
Like my previous post, the note draws an inspiration from the legal treatment of emissions credits. It observes similarity with Bitcoin but is careful to point out an important difference: a Bitcoin is mere information and does not come with a bundle of rights conferred by statute.
The note finds that an unjust enrichment claim is the most promising approach in English law to the recovery of a misappropriated bitcoin. Among the "property-like" remedies, however, the note observes that a claim for knowing receipt founded by a constructive trust is the most promising avenue. As my previous post has pointed out (at page 4 of the slide), this remedy constitutes an alternative avenue for recovery in some legal systems; it can indeed be the most potent one as in English law.