Abstract: Techniques are described for examining data that may be communicated to a recipient in an item such as a gift certificate. In some cases, the data may include personal information, financial data, or otherwise sensitive data. To prevent inadvertent leakage of sensitive data to unauthorized processes or individuals, the sensitive data may be placed in a portion of memory that is accessible by authorized software modules. The modules may execute in a container that has access to the portion of memory. In some cases, a module may expose functions that are callable from outside the container. The functions may examine the data to determine whether portions of the data comply with requirements. The return values of the functions may indicate the results of the examination of the data without communicating the examined data.