Just guessing, but if appending to the chain requires signatures from IBM / Walmart, then all you need is to get the blockchain from somewhere, and you can veri

Just guessing, but if appending to the chain requires signatures from IBM / Walmart, then all you need is to get the blockchain from somewhere, and you can verify it. With in-build non-repudiation. This is of course also possible with signed responses to queries. I think the advantage here is that the signatures are build into the data-store. This just simplifies verification and replication.