When Andrea tried to use her Discover Card at Home Depot, the clerk told her she needed to show ID. Alarmed with this apparent violation of the merchant agreement, she called Discover and was told the ID-checking violated no agreement and was in fact company policy.

Unless it was a rogue customer service rep Andrea spoke to, this could be a sign that yet another sacred merchant agreement standby may be fading away. As we reported earlier this month, Discover joined the ranks of Visa, AMEX and MasterCard by allowing merchants to institute $10 minimum purchases.

We contacted Discover HQ about this and were told that — unlike Visa and MasterCard, which do not permit merchants to check ID when the card is properly signed — “It’s at the merchant’s discretion to request ID.”

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