Pop Top Corp has added a Western District of Texas case against Amazon (6:21-cv-00315) to a campaign over highlighting text within e-books. The litigation begun last July with a Northern District of California suit against Rakuten (Rakuten Kobo), followed by two Southern District of New York cases, one against each of Elliott Advisors (Nook Digital f/k/a barnesandnoble.com), filed last August, and Ectaco, filed this past January. Early dispositive motions are under consideration in those earlier cases.