This feature lets you remove hidden or not-so-evident content that you do not want kept in the document when you distribute it, such as bookmarks, comments, attachments, metadata, etc. You should inspect and de-feature a copy of the original document or use Save As to make a copy if you need to retain the original.
To inspect your PDF document
Select Security > Security > Remove Elements.
You can also specify this dialog box to appear whenever a document is closed, or whenever it is attached to an e-mail. Do this under File > Options > Document. By default these choices are disabled.
In the Remove Document Elements dialog box, the categories of sensitive/hidden contents found in the current PDF document appear as active, selected checkmarks. Deselect those you want to retain. The categories are:
Bookmarks
Bookmarks are links referring to specific pages of a PDF document. You can view all bookmarks of a PDF document in the Bookmarks panel. Bookmarks usually indicate the document structure, but may also include sensitive words and phrases.
Comments
Comments usually refer to text markups and show the opinions of the author or reviewers. View all comments in the Comments panel (click the tool on the left of the View bar). Comments include notes, markups, drawing objects as well as file and sound attachments. Attachments added through the Attachments panel are not removed by this choice.
Document Attachments
Document-level attachments are files (both PDF and other formats) added to a PDF document as reference or related data. View all attachments in the Attachments panel (click the tool on the left of the View bar). Attachments added as comments are not removed by this choice.
Deleted content
Deleted parts (pages, text, images, cropped items) are not always actually removed from the PDF, they are just invisible. They could be restored by curious parties.
Destinations
You can place an icon in your PDF file and link it to an external file. When the icon is clicked, the file is opened. You can view destinations in the Destinations panel (click the Destinations tool in the Panel bar). In general destination files will not open if the PDF is distributed.
Embedded thumbnails
Thumbnails are miniature PDF pages often embedded in a PDF document. View page thumbnails in the Pages panel (click the Pages tool in the Panel bar).
Form fields and actions
Form fields in a PDF document are dynamic controls that contain interactive features. If this item is removed, all form fields are flattened and cannot be edited, filled in, or signed any more. (View form fields in the Form Control panel (click the Form Control tool in the Panel bar).
All JavaScript
JavaScripts are active components that perform commands or actions under specified conditions. If this item is removed, all JavaScripts will turn inactive.
Links
Links lead to some specific targets or actions. If you remove this item, the link texts or objects remain but the PDF not longer contains links.
Metadata
Metadata include information about the PDF document such as author, subject, keywords, date, copyright information, etc. Metadata can be searched by PDF search utilities. View the PDF metadata in your document at File > Info). If you click Properties, you can see them in the in Document Properties dialog box.
Embedded non-display data
This removes internal data not covered by metadata that is not normally visible, but can be viewed with PDF tools. This removes an embedded index, which may contain text that was subsequently redacted.
Click Select All to select all active elements or to remove all selections.
Click Remove to delete the content of the selected item(s).
Select File > Save to save the modified PDF document. Select Save As and enter a new filename if you want to keep the original PDF document.
Notes
All selected items will be permanently removed from the PDF document after you save the file. If you close the PDF document file without saving it, all operations are cancelled and you will have to repeat this process.
Removing Document Elements is usually done together with redacting, which is offered in Power PDF Advanced. After redaction is performed, an invitation to inspect the document is given. Redacting a document does not redact the content inside an already embedded index. To maintain document security, you should choose to remove embedded non-display data, in order to delete the index. You can re-index the document after redacting it; the removed texts will not enter the new index.
Removing Document Elements is similar to document flattening, which removes selected annotation types, or transforms them into document objects.