Introduction / Wesley M. Cohen and Stephen A. Merrill. - Patent quality / Are all patent examiners equal? Examiners, patent characteristics, and litigation outcomes. Iain M. Cockburn, Samuel Kortum, and Scott Stern. - Patent examination procedures and patent quality. John L. King. - Patent quality control: a comparison of U.S. patent re-examinations and European patent oppositions. Stuart J.H. graham, Bronwyn H. Hall, Dietmar Harhoff, and David C. Mowery. - Benefits and costs of an opposition process. Jonathan Levin and Richard Levin. - Patent litigation / Enforcement of patent rights in the United States. Jean O. Langouw and Mark Shankerman. - Patent litigation in the U.S. semiconductor industry. Rosemarie Ham Ziedonis. - Patents in software and biotechnology / Intellectual property protection in the U.S. software industry. Stuart J.H. Graham and David C. Mowery. - Internet business model patents. John R. Allison and Emerson H. Tiller. - Effects of research tool parents and licensing on biomedical innovation. John P. Walsh, Ashish Arora, and Wesley M. Cohen