I don't shop at Walmart. I just received this message for my platinum card.
Fraud Protection Alert
Please log into your account at AmericanExpress.com or call us at 1-800-824-9289.
For Your Security:
For your security, we regularly monitor accounts for possible fraudulent activity. Please review the attempted charge below which occurred within minutes of the timestamp of this message.
Transaction Date: 05/15/13
Merchant: WAL MART COM
Case Number: 799XX
Please log on to your account at AmericanExpress.com to verify this attempted charge. You can also call us using the number on the back of your Card or American Express Account Security directly at 1-800-824-9289. You should have your American Express Card handy when you call.
Some transactions are pre-authorized before the final sale. These can include purchases made at gas stations, hotels, and car rental merchants. Please note the amount shown above may not reflect the exact amount of your final transaction.
If we've already spoken to you about this matter, please disregard this message. No further action is required.
Thank you for your Cardmembership.
American Express Account Security
Fraud Prevention Network
You don't know what you can do when you don't know what you can't do.