One valid use case of non-repudiation that I can think of is the Poor Man's Copyright[0], where you email yourself your creative and have a timestamped record of when it existing.
What if you send the email from a reputable managed email service? That way, they're responsible for managing the keys, and can probably be trusted not to sign anything fraudulently.
Cheaper than paying for a digital signing service, but I imagine it wouldn't hold up as well in court.
Poor man's copyright is unfortunately quite tenuous and usually unenforceable.
At my start-up we've built an analogous system which instead uses a public blockchain for notarization (as dirty as that word has become). https://assembl.net or https://app.assembl.net if you'd like to try timestamping right away.
Non-repudiation here is useful, but the timestamping is the more important piece.
Yes, but that doesn't mean it can't be unenforceable. It simply means it hasn't passed the test of a court. However, isn't the same, from my limited research and knowledge, true for blockchain-based notarization?
DKIM does not offer cryptographic proof-of-existence or proof-of-time, which a blockchain does. That's the only functional difference, but crucial for copyright law.
Eh, fair question. Assembl is a pretty sought after name which we have the trademark on. I came up with the name after thinking it was necessary to "assemble" teams of scientists for collaborative research. I liked the name "Assembl" as it's the root for "assemble", "assembling", "assembly", etc.
are both infringers, but we haven't decided to go after them. The owner of https://assembl.com cannot be compelled to sell it, but can't sell it to anyone but us. For now, the focus is mainly on providing value to our userbase, as we grow these challenges are surmountable.
[0]: https://en.wikipedia.org/wiki/Poor_man%27s_copyright