American Express’ new blockchain technology could give the card issuer a trove of data on product purchases.
Amex has built a distributed ledger that merchants can use to tie card rewards to products they want to move off the shelf. For instance, if an auto insurance company wants to sell more policies or a coffee shop wants to serve more large coffees, it could offer American Express reward points for the featured items to make them more appealing. A merchant that wants to get people to download its app or join a program could offer the same enticement.
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