Last week, the retail giant won a patent for a system that would house medical records on a blockchain (the secure digital ledger technology). The purpose? To allow first responders to pull up medical data from a patient in the case of an emergency when he or she can’t communicate. Such a system would also theoretically involve a wearable device and an RFID scanner.

Here’s the abstract Walmart listed on its U.S. Patent & Trademark Office application.

A method for obtaining a medical record of a patient that is unable to communicate, wherein the medical record of the patient is stored on a blockchain, is provided, including receiving an encrypted private key and a public key associated with the patient stored on a wearable device of the patient, in response to a scanning of the wearable device of the patient at a scene of an emergency, wherein the encrypted private key is decrypted by a biometric signature of the patient, obtaining the biometric signature of the patient by scanning a bodily feature of the patient, decrypting the encrypted private key using the biometric signature of the patient to determine a private key associated with the patient, and accessing the medical records of the patient, using a combination of the public key and the private key associated with the patient, to access a local storage medium of the wearable device.

Let’s break that down into plainer terms. In essence, this system would depend on a wearable device which houses the actual patient data (on a blockchain). Another device, a biometric scanner, in conjunction with an RFID scanner, would be used to identify and then unlock the medical data stored on the wearable device. Two separate digital keys, one private and one public, would be at play, with the private key decrypted by scanning a major biometric feature of the patient (say, a retina image or fingerprint).

The purpose here is to reveal the medical information not only to first responders, but also with hospitals and health systems that the patient may eventually wind up at.

Walmart is reportedly in early talks to purchase health insurer Humana, a company with which it already has an extensive relationship. If its blockchain-driven electronic medical records system comes to fruition, that partnership could prove critical as a data depository.

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