A new patent application from retail giant Walmart shows how blockchain could be used to augment its digital offerings for consumers.

The document, released last Thursday by the U.S. Patent and Trademark Office, outlines a blockchain ledger which would track the items that stores sell to a particular customer. It’s the latest example of an intellectual property play by Walmart, which has filed a number of related applications and has also piloted the tech for tracking food products.

The proposed system would allow a customer to register the item after it’s bought for the first time. The customer would then be able to choose a price for a resale, with the system itself acting essentially as a digital marketplace, according to the application.

Perhaps just as notable is the fact that the application appears to work in details from another use case – distributed delivery tracking – that was outlined in a past patent filing.

Walmart’s latest application explains how a “distributed delivery record blockchain” would be updated as products move from the seller to the courier to the buyer, with new transactions signifying each step.

The company wrote:

“By one approach, the transfer from the seller to the courier may require signatures from both the sender and the courier using their respective private keys. The new transaction may be broadcasted and verified by the sender, the courier, the buyer, and/or other nodes on the system before being added to the distributed delivery record blockchain. When the package is transferred from the courier to the buyer, the courier may use the courier’s private key to authorize the transfer of the digital asset representing the physical asset from the courier to the buyer and update the delivery record with the new transaction.”

The idea of Walmart actually pursuing such a use case isn’t that far-fetched – last September, the retailer detailed how it was testing automated delivery solutions with a limited group of customers in California.

Walmart image via fotomak / Shutterstock