Trail disclosure is the leakage of privacy sensitive data, resulting from negligence, attack or abusive scrutinization or usage of personal digital trails. To prevent trail disclosure, data degradation is proposed as an alternative to the limited retention principle. Data degradation is based on the assumption that long lasting purposes can often be satisfied with a less accurate, and therefore less sensitive, version of the data. Data will be progressively degraded such that it still serves application purposes, while decreasing accuracy and thus privacy sensitivity. Categories and Subject Descriptors H.2.7 [Database Administration]: Security, integrity, and protection General Terms Algorithms, Management, Security, Human Factors Keywords Privacy, limited retention, data degradation