“The letters were wrong to imply we were looking at specific merchants,” said Susan Korchak, a company spokeswoman. The company uses hundreds of data points in making its decisions, she said, adding that the main factor in determining credit lines “has always been and still is the overall level of debt, relative to the card member’s financial resources.”

The company will still have plenty of other data to judge your creditworthiness, though. American Express executives have spoken candidly to investors and analysts about its deep dives into your data, though it’s safe to assume that other companies will also use such information if they think it will be useful.