Align Technology Inc. sued ClearCorrect Holdings Inc., ClearCorrect Operating LLC and Your Smile Direct LTD of Dublin for patent infringement in the Chancery Division of the High Court of Justice of the U.K.

Align said ClearCorrect infringes four of its European patents by marketing ClearCorrect's clear aligners, and that Your Smile Direct infringes three Align patents by marketing ClearCorrect aligners under the Your Smile Direct brand.

U.S.-based Align Technology, maker of the Invisalign orthodontic system, also said it recommenced its stayed infringement litigation against ClearCorrect in federal district court in Houston.