Incriminating or sensitive email messages can now be instructed to destroy themselves. Disappearing Inc is a San Francisco-based start-up whose software encrypts, authenticates, tracks and deletes email messages – including those stored on backup tapes or forwarded to third parties. Unprotected email is like a postcard, explained CEO Maclen Marvit. The wrong people can read it, there is no proof of delivery and its stays around forever. Our email policy management system protects messages while they are in use, and then makes them expire whenever the company chooses.

It works like this: every email message is encrypted with a unique key to prevent unauthorized readers from gaining access. Receivers must authenticate themselves. Records are kept of every time an email message is read, and when a particular key is destroyed, the message associated with it can never be read again. When a message is deleted, all copies are rendered unreadable. (This feature alone might have prevented many of Microsoft Corp’s embarrassments at the hands of Department of Justice lawyers.)

The whole system is designed to give network administrators the power to specify and enforce policies on how email messages are retained. As an example, a publicly traded business might keep permanent records of correspondence only when that correspondence is about SEC compliance, deleting everything else after ninety days.

The software works with free web-based mailers, Microsoft Outlook, Netscape Mail and Eudora. Users should not have to change the way they read, write or file their messages. The system should also play nicely with Public Key Infrastructure (PKI) technologies and with automated email response management systems like eGain and Kana. With a head count of 20, Disappearing has already attracted funding from Red Rock Ventures, Angel Investors LLP and Ben Rosen, chairman of Compaq Computer Corp.