Document flattening lets you prepare a commented or annotated document for distribution. This removes such items from the PDF or transforms them into document objects that are selectable, movable and editable, for instance with the Edit Object tool. The flattened objects are no longer annotations and are removed from the Comments Panel.
To retain a fully-featured original, apply flattening to a copy of the document.
To flatten a PDF choose Advanced Processing > Process > Flatten File. In the Flatten dialog box select which annotation types or other elements you wish to flatten and click OK.
Flattening cannot be undone, and all other undo operations are removed. Here is how each item is handled:
Drawing objects
As annotations, these are placed by a drawing tool and can be selected by that same tool or the Select or Hand tools. On flattening they are removed from the Comments list and transformed to document objects that can only be selected and modified with the Edit Object tool.
Attachments
To place an attachment as an annotation, click the Attach File or Attach Sound tool and click a page location. An icon appears; a tooltip shows the attachment name and author – double-clicking opens the file. Such attachments are listed in the Comments panel and the Attachments panel. On flattening they are removed from the Comments and the Attachment lists. The file can no longer be opened, only the icon remains showing where the attachment previously existed.
Note: Attachments added in the Attachments panel are not affected by flattening: it acts only on attachments placed as annotations.
Text Boxes
As annotations, these are placed by the Text Box tool and can be selected by that same tool or the Select or the Hand tool. On flattening they are removed from the Comments list and transformed to document objects that can still be read, but can only be selected and modified with the Edit Object tool.
Notes
As annotations, these are placed by the Note tool. A double-click displays note text. On flattening they are removed from the Comments list and deleted; only the icon remains showing where the note previously existed.
Stamps
As annotations, these are placed by double-clicking or drag-and-drop from the Stamps panel. They can be selected by Comment tools or the Hand tool. On flattening they are removed from the Comments list and transformed to document objects that remain visible, but can only be selected and modified with the Edit Object tool. With the latter you are likely to select only one element from the stamp. Right-click and choose Select Parent Group to select the whole stamp.
Layers
Layers are not annotations. They are listed or created in the Layers panel. On flattening with the Flatten dialog box, all layers are merged into one, with no Undo facility. The Layers panel offers two commands: Flatten Layers and Merge Layers. Flatten Layers merges all layers into one, but Merge Layers allows you to choose which layers should be merged and which layer accepts the merged ones.
Text Markup
On flattening, deletions, highlights and other text markups remain visible, but can no longer be selected. Text that was inserted as new or replacement text is lost; only the insert symbol ^ remains to show where insertions were made.
Form
On flattening, all form controls cease to be active and can no longer be selected with the Hand tool. They can only be selected and modified with the Edit Object tool.
3D
On flattening, all 3D functionality is removed, the object becomes 2D can only be selected and modified with the Edit Object tool.
Movie
On flattening, the Movie ceases to be available, only the icon remains showing where the movie previously existed.
Redaction
When a file to be flattened contains real redaction, flattening the file conserves them. The black rectangles that block out redacted content can be selected and moved with the Select Object tool, but the removed content cannot be seen or searched. When a file to be flattened contains elements that are only marked for redaction, flattening the file does not conserve the redaction. The black rectangles that block out content marked for redaction can be selected and moved with the Select tool, but then the underlying content remains visible and searchable.
Tip
A similar process to document flattening is Document Inspection, in which selected item types are removed from the document.