PDF files have much less scope for incorporating metadata than HTML. The fields within ‘Document properties’ are the only ones we can use. These are:

Title

apply the same principles used for HTML titles

Author

apply the same principles used for HTML creators

Subject

apply the same principles used for HTML description

Keywords

apply the same principles used for HTML keywords

How

In Acrobat click on File > Document Properties >Description and complete as many fields as possible.

Metadata in PDF's can either be imported from the source Word document or can be added directly using Adobe Acrobat. The preference is the have the full and correct metadata in the source Word document. In Word See File and Properties.