Patents image (IMAGE) West Virginia University Caption Pharmaceutical companies use patent thickets — multiple patents covering the same drug — to manipulate the patent system in order to maintain an advantage over generic counterparts, according to research from Sean Tu, a West Virginia Unversity law professor. Credit WVU Graphic/Peter Habuda Usage Restrictions NONE License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.