We've been asked a couple of times why Acrobat needs two versions of the highlight tool, and it's all down to this ability of the second type to contain a note. What started life as a 'highlight' has become a 'text note' as a result of entering something into the note field. Open the PDF and go to File menu>Properties>Security. If you are still not able to remove the highlight, then there is a possibility that the PDF is secured. The fifth button is the 'text note' tool, and this is the annotation type Acrobat uses if you type something into the popup field of a 'regular' highlight, and hence this is why you see the highlight and the tiny speech bubble icon on the page. Select the comment box for highlighted text and right click from your mouse. The first four do not display the sticky note icon even with a note attached, they simply display a tooltip (or open the note itself if you double-click them), so again there's no speech bubble on the icon. The bottom row contains text annotations. In the Comment tab, select Area Highlight.Then click and drag to make a shape you want to mark up. You can use the Area Highlight command to mark important area as a means of memory retention or for later reference.

The second-left on the top row is the 'regular' Highlight tool - this draws the colored block over a text selection without any sticky note attached it's all it can do (which is why the icon doesn't have a speech bubble overlay, as the next two have). Answer: A: Answer: A: You can remove highlighting from selected PDF text by right-clicking on the selection, and choosing the transparency item from the pop-up menu. This article will tell you how to mark up an area with a highlight color in PDF with Foxit PDF Editor. The Acrobat X Annotations panel explains it a little clearer:

Remove highlights from pdf