The very real threat of sending out sensitive and commercial information within Microsoft Office documents can be effectively prevented with new software, claims its developer Workshare.

Office documents can give away e-mail addresses and sensitive comments, among other details, through the metadata stored with them. Although such data is hidden by simple viewing, it is simply and easily revealed by using the "Show Markup" command within the revelant applications.

Where documents have been worked on by several people then pre-final version text, comments and reviewers' notes can be shown, sometimes in embarrassing detail - as SCO found out in March last year. A document submitted in its lawsuit against DaimlerChrysler showed that SCO has originally planned to sue the Bank of America.

But Office documents also routinely add contributing authors' names and e-mail addresses in shared documents. They are classed as high security risks in Workshare's Trace product beta. Workshare's Trace is a metaware utility that detects the hidden data in Word, Word Email, Excel and PowerPoint documents. Other high security risk items is finds and lists are macros, comments, speaker notes, hidden columns and slides, and white text. Sensitive information could be deliberately sent inside an otherwise safe document by incorporating it as white-coloured text against the default white document background.

The latest version of Workshare's Protect product will detect, and remove, such hidden data. It will also alert you when an e-mail is to be sent with attachments that contain hidden data.

Microsoft's own remove hidden data plug-in does the same.