Evan Schuman's StorefrontBacktalk

Next let’s consider the benefits of storing cardholder data. We need to make one point clear from the start: The card brands do not require merchants to keep cardholder data. That is the case, no matter what you may have heard. Your acquirer or processor may need to keep the data, but if you choose to do so, I hope you are getting something in return.

You definitely should keep what I call “payment data,” which includes date, amount, name, and either the first six or the last four digits of the PAN. All this information is out of scope for PCI, and the data can be used to locate any card transaction from your acquirer for chargebacks or refunds. So far, then, your benefits from storing PAN data add up to $0.

Some retailers keep PAN data for loyalty programs or other post-purchase applications. Re-coding these applications to use a different identifier will cost money. Your risk assessment should lead you to ask if you might use a secure one-way hash instead of the PAN.

The hash will be unique to the card, and it also will be out of PCI scope. It will cost to change your systems to use the hashed values, but that amount may be a lot less than the cost of storing and protecting all those PANs.

The hospitality industry presents an interesting challenge, as hotels like to retain guests’ PANs after checkout to cover any additional charges. The business case here is whether the benefits of the late charges for those $2 bottles of water (that the guest will dispute anyway) outweigh the costs of retaining the PAN data. There may be situations where keeping cardholder data makes sense. For example, hotels might want to retain it when housing rock groups that trash their rooms on a regular basis. But I have seen cases where, as much as we tried, the hotel could not cost-justify storing the data based on post-checkout charges.

The risk analysis you prepare for your PCI compliance presents yet another opportunity to reduce your risk and costs. If you decide to keep 60 days of PANs for exception item processing as a favor to your acquirer, maybe you can reduce that to 30 days. If you use PAN data for velocity checking or loyalty programs, maybe you can use a hash value instead.

Whether or not you act is almost secondary. The key thing is to use the work you have done to ask some direct questions. How you choose to answer those questions can have significant implications on your risk profile and your budget.

How do you use your PCI risk assessment? Whether or not we agree, I’d like to hear your thoughts. Either leave a comment or E-Mail me at wconway@403labs.com.