That's good information to know if it was Word 2007 or Word 2010 as they might not compress data streams when exporting to a PDF. LibreOffice (and presumably Apache OpenOffice) does compress the data stream.
As I noted I use PDFCreator and below show the "Options" page for PDF generation showing the compression option which is set as default.
The objective is simple. If one runs up against Verizon's overly zealous spam and content filters when sending email, put the information in a format that does not have the content as "Clear Text" and the email will get past the spam and content filters.
This can be using a format such PDF that uses compression, placing the text in a graphic or encapsulating data in a ZIP file. Anything that obfuscates that text that may be caught in the filter(s).
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