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Hi tybi-seochat! I'm afraid there's no native way in Open Site Explorer to pull all of your links to PDFs. One option, though, would be to download the CSV with all of your links, and then filter out the ones whose targets don't end in .pdf. Keep in mind, though, that even that likely won't be every link. The Mozscape index is designed to give you a great sense of your overall link profile, but it isn't exhaustive.