If the tags in a PDF file in Acrobat appear to be overly complicated and cannot be managed, it is possible to re-tag an already tagged document. To do this, first remove all existing tags from the tree. Use the Touch Up Reading Order tool to remove or replace the current structure. If the document contains mostly text, select a page and then remove headings, tables, and other elements to create a cleaner, simpler tagging structure.

Remove All Tags from a PDF Document

The Touch Up Reading Order tool is very useful to create tags in untagged PDFs or to add new tags to an existing tagged structure, but the Add Tags to Document command provides more detail. For example, tags such as paragraphs, bulleted and numbered lists, line breaks, and hyphens are available from Add Tags to Document. Before clearing the existing structure, make sure that manual tagging is the only recourse.

To remove the tags from the entire PDF document, do the following:

1. Open the Tags panel and select the root (topmost) tag, Tags.
2. In the Tags panel, choose Options > Delete Tag.
   
   

Note: The Clear Page Structure command in the Touch Up Reading Order dialog box removes all tags from the currently visible pages and not from any pages that are not visible.

Replace the Existing Tag Structure on a Page

This process works best in pages that contain a single column of text. If the page contains multiple columns, each column must be selected and tagged individually.

1. Select the Touch Up Reading Order tool.
2. In the document pane, drag to select the entire page. The selection includes both text and non-text elements.
3. Control-drag/Command-drag around non-text page elements—such as figures and captions—to deselect them, until only text is selected on the page. Click Text in the Touch Up Reading Order dialog box.
4. In the document pane, select a non-text page element, such as a figure and caption, and click the appropriate button in the dialog box to tag it. Repeat until all page content is tagged.
   

To perform more advanced reading order and tagging tasks—such as tags table of contents, adding replacement (actual) text for blocks of text, removing obsolete tags, and adding replacement (actual) text to links—it may be necessary to use the Content panel and the Tags panel, which provide an advanced set of tools and features for manipulating PDF tags. The Touch Up Reading Order tool generally changes and synchronizes both of these panels, but the two can become out of sync.

Content Panel

Use the Content panel to correct reflow problems in a PDF that cannot be corrected by using the Touch Up Reading Order tool. Take note that it is easy to damage a PDF by editing content objects as removing a content object will remove the object from the visual page. Be familiar with the PDF structure before changing anything. For comprehensive information about PDF structure, refer to the PDF Reference First Edition: Adobe Portable Document Format Version 1.7, on the PDF reference page (English only) of the Adobe website.

The Content panel provides a hierarchical view of the objects that make up a PDF, including the PDF object itself. Each document includes one or more pages, a set of annotations (such as comments and links), and the content objects for the page, consisting of containers, text, paths, and images. Objects are listed in the order in which they appear on the page, similar to tags in the logical structure tree. However, objects in the Content panel do not require tags to view or change the object structure.

To display the Content panel, choose View > Show/Hide > Navigation Panes > Content from the Acrobat DC menu.

Click the plus sign (+) (Windows) or the triangle (Mac OS) next to the document name to view each page content entry. Control + click expands the entire content tree. The Content panel provides an option to show the corresponding tag in the Tags panel by activating the context menu and choosing “Show in Tags Panel”.

Note: It is helpful to have Acrobat highlight items in the document view when the associated item in the Content panel is selected. By default, Acrobat will highlight content in the tag and content panel trees. To toggle the highlight feature on and off, from the Options Menu, select “Highlight Content” (See “Figure 34. Set Highlighting On for the Content Panel”).

Containers or objects can be moved by selecting them and doing one of the following:
Drag it to the desired location.

• Choose Cut from the Options menu, select the tag above the location, and choose
• Paste from the Options menu (Standard Windows and Mac keystrokes also work).

Note: Container elements can’t be pasted directly to page elements. To move a container to another page, cut the container to move, select a container on the page to move the container to, and choose Paste from the Options menu. Then, drag the container out one level to the desired location.

Content Panel Options

In the Content panel, use the Options menu or right-click an object to choose from the following options:

• New Container. Adds a new container object at the end of the selected page or container.
• Edit Container Dictionary. Specifies the dictionary for the container. Errors in this dialog box may damage the PDF. This option is only available only for containers that include dictionaries.
• Cut. Cuts and copies the selected object (not the related page content).
• Paste. Pastes content directly below the selected object at the same hierarchical level.
• Paste Child. Pastes content into the selected object as a child content item.
• Delete. Removes the object (not the related page content) from the document.
• Find Content From Selection. Searches for the object in the Content tab that contains the object selected in the document pane.
• Find. Searches for unmarked (untagged) artifacts, content, comments, and links. Options allow page search or document, and to add tags to found items.
• Create Artifact. Defines selected objects as artifacts. Artifacts are not read by a screen reader or by the Read Out Loud feature. Page numbers, headers, and footers are often best tagged as artifacts.
• Remove Artifact. Removes the artifact definition from the selected object.
• Highlight Content. When selected, highlights appear in the document pane around content that relates to a selected object in the Content tab.
• Show Metadata . Allows viewing and editing of image or object metadata.
• Properties. Opens the Object Up Properties dialog box.

The Tags panel allows the viewing and editing of tags in the logical structure tree, or tags tree, of a PDF file. Tags in panel appear in a hierarchical tree order that indicates the reading sequence of the document by assistive technologies such as screen readers. The first item in this structure is the Tags root. All other items are tags representing standard PDF structure elements and are children of the Tags root. Tags use coded element types that appear in angle brackets (< >). Each element, including structural elements such as sections and articles, appear in the logical structure order by type, followed by a title and the element’s content or a description of the content. Structural elements are typically listed as container—or parent—tags and include several smaller elements—or child tags—within them. The tag description is not seen by users of assistive technology and can be used by the author to provide comments during the tagging process.

Note: It is possible to directly change tag types by pressing F2 or double clicking the tag name in the tree. Tag names are case-sensitive, and care must be taken to properly enter the angle bracket if this method is used to change the type of a tag.

Many tagging issues can be corrected by using the Touch Up Reading Order tool, but it is necessary to use the Tags panel to address detailed tagging of tables and substructure items—such as paragraphs, lists, and sections that require multiple languages. First consider using the Autotag Document feature and the Touch Up Reading Order tool and then use the Tags panel to modify the tags.

Note: Important! Operations performed in the Tags panel cannot be undone with the Undo command. Save a backup copy of each document before beginning work on it in the Tags panel.

To display the Tags Panel Choose View > Show/Hide > Navigation Panes > Tags.

• Expand or collapse the tag for an individual element or section by clicking on it.
• Expand or collapse the entire tree or a node on the tree that has children with Control-click the plus sign (Windows) or Option-click the triangle (Mac OS) next to the Tags root to show all tags in the logical structure tree.

Note: You may find it helpful to toggle whether Acrobat highlights items in the document view when the associated item in the Tags panel is selected. From the Tags panel options menu, “Highlight Content” can be turned on or off—it is on by default in Acrobat DC. (See “Figure 34. Set Highlighting On for the Content Panel”). It is also possible to show the corresponding content tag in the Content panel from the Tags panel by activating the context menu and choosing “Show in Content Panel”.

Edit Tags in the Tags Panel

There are many actions that can be taken on a tag within the Tags panel. These include but are not limited to:

• Adding a tag
• Creating a tag from the document selection
• Editing a tag title
• Changing a tag location
• Changing the tag type for an element
• Deleting a tag

To reveal the Object Properties (See “Figure 36. The Object Properties Dialog: Tag Tab”) for any tag, select the desired tag in the Tags panel and perform one of the following:

• Right click (or activate the context menu) and select Properties from the context menu.
• Select Properties from the Tags Panel Option Menu.

Edit a Tag Title

From the Tags panel:

1. Expand the section of the desired logical structure to edit.
2. Select the desired tag to edit.
3. Choose Properties from the Options menu.
4. Enter text in the Title box.
5. Select the Close button.

Note: The F2 command can also be used within the tags tree to edit the tag type and title. Make sure that the tag type does not get overridden.

Move a Tag

From the Tags panel:

1. Expand the Tags root to view all tags.
2. Select the Tag icon of the element to move.
3. Then do one of the following:
   • Drag the tag to the desired location. When dragging, a line appears at available locations to place the tag.
   • Choose Cut from the Options menu, and select the tag that appears above the desired location to paste the cut tag. From the Options menu, choose Paste to move the tag to the same level as the selected tag, or choose Paste Child to move the tag within the selected tag.
     
     

Change the Element Type

From the Tags panel:

1. Expand the section of the logical structure that to change.
2. Select an element.
3. Choose Properties from the Options menu or from the context menu.
4. Choose a new element type from the Type menu.
5. Select the Close button.

Tags Panel Options

In the Tags panel, use the Options menu or right-click a tag in the logical structure tree to choose from the following options:

• New Tag: Creates a new tag in the logical structure tree after the currently selected item. Specify type and title of the new tag.
• Cut : Removes the selected tag from its current location and puts it on the clipboard.
• Paste: Places the tag on the clipboard into the location specified, replacing the selected tag.
• Paste Child: Places the tag on the clipboard into the location specified, as a child of the selected tag.
• Delete Tag: Removes the selected tag.
• Find Tag From Selection: Searches for the tag in the Tags tab that contains the text or object selected in the document pane.
• Create Tag From Selection: Creates a new tag in the logical structure tree after the item selected in the document pane. Specify the type and title of the new tag.
• Find: Searches for artifacts, OCR suspects, and unmarked (untagged) content, comments, links, and annotations. Options allow searching the page or document and adding tags to found items.
• Change Tag To Artifact: Changes selected tags to artifacts and removes the tagged content from the structure tree.
• Copy Contents To Clipboard: Copies all content contained within the selected tags.
• Edit Class Map: Allows the addition, modification, and deletion of the class map, or style dictionary, for the document. Class maps store attributes that are associated with each element.
• Edit Role Map: Allows the addition, changing, and deletion role maps for the document. Role maps allow each document to contain a uniquely defined tag set. By mapping these custom tags to predefined tags in Acrobat, custom tags are easier to identify and edit.
• Tag Annotations: When selected, all new comments and form fields are added to the tag tree; existing comments and form fields aren’t added to the tag tree. Highlight and Underline comments are automatically associated and tagged with the text that they annotate and don’t require this option.
• Document Is Tagged PDF: Flags the PDF as a tagged document. Deselect to remove the flag.
• Highlight Content: When selected, causes highlights to appear around content in the document pane when selecting the related tag in the Tags tab. The default option is on.
• Show in Content Panel: Shows the Selected tag’s contents in the Content panel.
• Show Metadata: Opens a read-only dialog box that contains reference information about the selected tag.
• Properties: Opens the Object Properties dialog box.

Create a New Child Tag

From the Tags panel:

1. Select the node the tag should appear inside.
2. Choose New Tag from the Options menu.
3. Select the appropriate tag type from the Type pop-up menu, or type a custom tag type, title the tag (optional).
4. Select the OK button.
   

Add Tags to Comments

When tags are added to a PDF that includes comments, the comments are tagged as well. However, if comments are added to a PDF that’s already tagged, comments are untagged unless comment tagging is enabled first.

Note: To Enable comment tagging in a PDF, in the Tags panel, choose Tag Annotations from the Options menu. Comments or markups that are added to the PDF are tagged automatically.

If a document contains untagged comments, they can be located in the logical structure tree and tag them by using the Find command in the Tags panel.

1. In the Tags panel, choose Find from the Options menu.
2. In the Find Element dialog box, choose Unmarked Comments from the Find pop-up menu, and click Find.
3. When the comment type appears in the Type field (for example, Text), activate Tag Element, choose Annotation from the Type pop-up menu in the New Tag dialog box, and then activate the OK button.
4. In the Find Element dialog box, activate the Find Next button to locate and tag all comments, and then activate the Close button.
   

Add Links or Form Fields

Links and form fields should have already been added to the document with the appropriate tags if the previous steps in this document were followed. However, if the form fields or links were already present and tags already existed in the document, use the following steps to make the form field or link accessible. It is NOT enough to simply place the content under a link or form tag in the tags tree -- an appropriate object tag must also be present as a child of the parent link or form tag in the tree along with the corresponding text node.

From the Tags panel:

1. Locate the parent element in the tree to insert the desired link or form field (if the appropriate node does not exist create it first).
2. Choose Find from the Options menu.
3. In the Find Element dialog box, choose “Unmarked links” to find and tag links or “Unmarked annotations” to find and tag form fields from the Find pop-up menu.
4. Select the Find button.
5. If the item is located, activate the Tag Element button.
6. In the Find Element dialog box, select the Find Next button to locate and tag all comments.
7. Select the Close button.

When a language is set for an element in the tag tree that language applies to all content under the tag. If the different language is part of the same tag it must first be split out into a separate tag. An easy way to do this is to create a new Span tag below the current element and then arrange the text content under the current tag in the appropriate location.

1. Select the text node that must be split.
2. Activate the context menu and choose New Tag.
3. From Type, choose Span and Activate the OK button.
4. Select the new span tag.
5. Select the text in a different language in the document pane.
6. Right click or activate the context menu on the new span element in the tag pane.
7. Choose “Create Tag from Selection”.
8. Reorder any text that appears after the span element so it appears after the span element (the text should appear as two separate text nodes under the parent element as siblings of the span element).

To set the language:

1. Select the tag in the Tags tree that contains the content in a different language.
2. Right click to activate the context menu.
3. Choose Properties from the Options menu.
4. Select the Tag tab of the Object Properties dialog.
5. Select a language from the Language drop-down.
6. Activate the Close button.

Note: The language that is specified for an element also applies to all elements nested under it in the logical structure tree.

Proceed to Step 8: Add Alternative Text.