A-PDF Content Splitter ( http://a-pdf.com/content-splitter/index.htm ) can separate PDF files by keywords. It can locate the position based on the rules you set. And then extract and compare the text, lastly generates series of small files. When you set the rules, you can customize your output PDF files. For more: http://a-pdf.com/faq/index.php?title=is-there-a-way-to-add-password-to-protect-pdf-file-with-a-pdf-content-splitter .