lk/data/pdf_erasure.md

title	tags
PDF Metadata Erasure	Metadata Ghost Script gs .pdf

You cannot erase pdf metadata with exiftool (it only appends your changes). To delete pdf metadata, you'll need gs.

Make a text file called 'pdfmark.txt'.

[ /Title ()
/Author ()
/Subject ()
/Creator ()
/ModDate ()
/Producer ()
/Keywords ()
/CreationDate ()
/DOCINFO pdfmark

Then run:

gs -o output.pdf -sDEVICE=pdfwrite "$FILE".pdf pdfmark.txt