Retailers often ask customers making a credit card purchase to provide their zip code. The assumption is that the information is needed to confirm that the card is valid.

But there have been an increasing number of reports that businesses are using the customer's name and zip code to put together a much more complete portfolio, possibly including their mailing address, telephone number and email.

This practice may be illegal under certain circumstances. In California, the Song-Beverly Credit Card Act of 1971 makes it a crime to request and then record personal information from a customer paying with a credit card.

A Seattle law firm, Hagens Berman LLP, says it is investigating Nike, Inc. after reports that the company did just that.

Third-party vendors

The firm began its investigation after receiving reports that Nike customers were being asked for their zip codes upon making a purchase with a credit card at a Nike store. The firm believes that Nike may have then employed third-party vendors to use the first and last name of the customer and their zip code together to narrow down customers' home addresses.

The firm said it is interested in talking to consumers who made a purchase at a Nike store with a credit card and complied with a request for their zip code. would also like to hear from consumers who've had this experience. Please use the complaint form to do so.