NSA issues guidelines on redacting metadata

UPI story: "The National Security Agency has issued technical guidance for U.S. officials on redacting or editing sensitive documents for release following a series of embarrassing incidents in which so-called metadata stored in electronic formats like Microsoft Word or Adobe PDF files has been accidentally exposed."

The story talks about a kind of metadata that gets passed from Word to PDF called "undo stack," which is a list of every editing change made in the file, saved by the program so that they can be reversed using the "undo" function.  The NSA's 14 page guide, entitled Redacting with Confidence: How to Safely Publish Sanitized Reports Converted from Word to PDF, is available in PDF (naturally).