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Eighteen jurisdictions have ethics opinions on metadata. All of them suggest that a lawyer who is sending an electronic document should take reasonable precautions to prevent disclosure of confidential information. While technically not metadata, the comments and tracked changes in a Microsoft Word document do present a significant opportunity to unintentionally expose confidential information. There are many ways to remove and reduce exposure of metadata, but one very important aspect is that the sender is aware of what is being sent. In some cases you may fully intend to send a document with comments and tracked changes.
Whether intentional or not, a notification that a document you are saving, sending, or printing has tracked changes or comments could be useful. Fortunately you can do exactly that with a setting in MS Word. In Word 2010-13 go to File – Options – Trust Center – Trust Center Settings – Privacy Options and check the box that says “Warn before printing, saving, or sending a file that contains tracked changes or comments”.
Once this option is checked if you click to save or save as, print to a physical printer or to PDF, save to PDF or use a PDF conversion tool like Acrobat or Nuance, or use any command under the “Save and Send” menu you will get a warning that the document has either comments and/or tracked changes and asks you to click yes to continue. However, the warning system is fallible because if you attach the file from an email program, such as MS Outlook you will get no notice.