Wal-Mart Stores Inc. is thinking about using sensor technologies to track how much detergent a family has used or when milk is about to expire, according to a patent application made public Thursday, a sign the retailer is exploring new ways to fend off Amazon.com Inc.

The system proposed by the retailer could use sensors in homes and attached to products like toothpaste, milk or razors to trigger automatic delivery of another box or suggest related products to buy, all while collecting consumer behavior data to tailor marketing, says the application on the U.S. Patent and Trademark Office website.

The proposed system is an advanced version of subscription services already widely available through companies like Amazon.com andTarget Corp.  Amazon lets shoppers use a mobile phone to scan a product for home delivery and Dash Buttons, small brand specific devices that let shoppers order products like Colgate toothpaste by pushing a button.

Wal-Mart’s patent filing describes a system with a variety of sensor technologies inside products and homes including radio frequencies, Bluetooth, or bar-code scanners to track how often a product is used, where it moves in a home or what best to market to a shopper next.

For example, clothes could be “tagged,” then tracked as they enter a person’s home for the first time, says the patent application. Then the system could track the clothes going into a washing machine, helping to predict the number of times the clothes are worn and washed. “When a certain threshold was set by the manufacturer as to the durability of the articles, a new set of clothes may be automatically ordered,” says the filing. A carton of milk near its “use by” date could trigger a reminder for the shopper to drink it or order a new one for delivery.

A Wal-Mart spokesman declined to comment on the system described in the filing. It is unclear if Wal-Mart is currently testing something similar. It is common for companies to file patents for ideas that never become products.

The vast majority of Wal-Mart’s patents are related to stores or e-commerce efforts, not internet-connected devices used in shopper’s homes, says CB Insights, a research firm that first discovered the Wal-Mart patent application. The patent, made public Thursday, was originally filed in October.

Source: The Wall Street Journal