Or you know, trusted timestamps and cryptographic signatures via normal PKI. A Merkle tree isn’t worth shit legally if you can’t verify it against a trust outside of the tree.

All of the blockchain bullshit miss that part - you can create a cryptographic representation of money or contracts, but you can’t actually enforce, verify or trust anything in the real world without intermediaries. On the other hand, I can trust a certificate from a CA because there are verifiable actual real-world consequences for someone if that CA breaks legal agreements.

I’ll use a folder of actual papers, signed using a pen. Have some witnesses, make sure they have a legal stake and consequences, and you are golden.