I think way he meant a hashed chain: one where the history is tamper proof. The important part is that the data and logic used to process claim is digitally documented and sealed by hash. You get a copy of the hash in your claims. The hash chain is public or has to be given to an independent third-party. If you get into a kicking contest in court, the company they have to reproduce documentation with the hash. The hashing prevents forging the original documents in the process.