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Anrews Kurth

Mark Lemley
Mark Lemley
William H. Neukom Professor of Law
Stanford Law School

Click here for Professor Lemley's faculty listing

Rethinking Assignor Estoppel

Click here for the Spring Lecture Invitation

Thursday, March 24, 2016



Coronado Club

To RSVP or for further information, contact
ipil@uh.edu or 713.743.2180
One Hour of CLE Credit

Mark Lemley is the William H. Neukom Professor of Law at Stanford Law School and the Director of the Stanford Program in Law, Science and Technology. He teaches intellectual property, computer and internet law, patent law, trademark law, antitrust, and remedies.

Professor Lemley is the author of seven books (most in multiple editions) and 146 articles on these and related subjects, including the two-volume treatise IP and Antitrust. His works have been cited more than 200 times by courts, including 11 United States Supreme Court opinions, and more than 13,000 times in books and law review articles, making him one of the five most cited legal scholars of all time. He has published nine of the 100 most-cited law review articles of the last 20 years, more than any other scholar, and a 2012 empirical study named him the most relevant law professor in the country.

His articles have appeared in 22 of the top 25 law reviews and in multiple peer-reviewed and specialty journals. They have been reprinted throughout the world and translated into Chinese, Japanese, Korean, Spanish, Italian, and Danish. He has taught intellectual property law to federal and state judges at numerous Federal Judicial Center and ABA programs, has testified seven times before Congress, and has filed numerous amicus briefs before the U.S. Supreme Court, the California Supreme Court, and the Federal Circuit courts of appeals.

Professor Lemley clerked for Judge Dorothy Nelson on the United States Court of Appeals for the Ninth Circuit. He is a founding partner of Durie Tangri LLP, litigating and counseling clients in all areas of intellectual property, antitrust, and internet law. He also is a founder and board member of Lex Machina, Inc., a startup company providing data and analytics regarding IP disputes to law firms, companies, courts, and policymakers.

In his spare time, he enjoys cooking, travel, yoga, and feeding his addiction to video games (at this writing, Witcher 3: Wild Hunt).

Rethinking Assignor Estoppel

As patents have become increasingly important in society, we have focused more attention on the problem of bad patents. The Supreme Court and the Federal Circuit have repeatedly emphasized the public interest in testing the validity of patents, weeding out patents that should not have been issued. And Congress has created a number of new mechanisms to make it quicker and easier to identify and eliminate invalid patents.

But there is one important group of people the law systematically prevents from challenging bad patents. Curiously, it is the very group who may have the most insight into the problems with the patent: the inventors themselves. The century-old doctrine of assignor estoppel precludes inventors who file patent applications from later challenging the validity or enforceability of the patents they receive. The stated rationale for assignor estoppel is that it would be unfair to allow the inventor to benefit from obtaining a patent and later change her tune and attack the patent when it benefits her to do so. But the Federal Circuit has expanded the doctrine in a variety of dimensions and applied it even when the benefit to the inventor is illusory. Further, the doctrine misunderstands the role of inventor-employees in the modern world. And it interferes substantially with the goals of both employee mobility and the assessment of patent validity.

It is time to rethink the doctrine of assignor estoppel. The doctrine in its current expanded form is out of touch with the realities of both modern inventing and modern patent law, and it interferes with both the invalidation of bad patents and the goal of employee mobility. I explore whether the doctrine can and should be saved in a more limited form.



JEANNE FROMER2015 JEANNE FROMER, Professor of Law, New York University School of Law
Should the Law Care Why Intellectual Property Rights Have Been Asserted?

Commentator: Richard Phillips

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Julie CohenEvent Invitation2014 JULIE E. COHEN, Professor of Law, Georgetown University Law Center
Post-Industrial Property

Commentator: Bart Showalter

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David McGowanEvent Invitation2013 DAVID MCGOWAN, Lyle L. Jones Professor of Competition & Innovation Law and Director, Center for Intellectual Property Law & Markets, University of San Diego School of Law
The Unfallen Sky: Assessing the Relative Effectiveness of Legal and Market Adaptations to Technological Change


Commentator: Jacqueline Lipton

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R. Anthony ReeseEvent Invitation2012 R. ANTHONY REESE, Chancellor's Professor of Law, University of California - Irvine School of Law
What Does Copyright Law Owe the Future?

Commentator: Paul R. Morico

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Paul GoldsteinEvent Invitation2011 PAUL GOLDSTEIN, Stella W. and Ira S. Lillick Professor of Law, Stanford Law School
Copyright on a Clean Slate

Commentator: Phillip Page

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Douglas LichtmanEvent Invitation2010 DOUGLAS LICHTMAN, Professor of Law, UCLA School of Law
Pricing Patents: The RAND Commitment


Commentator: Gordon White

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William O. HennesseyEvent Invitation2009 WILLIAM O. HENNESSEY, Professor of Law and Chair, Intellectual Property Graduate Programs, Franklin Pierce Law Center
Thirty Years (and More) of IP in China: A Personal Reflection

Commentator: Margaret (Meg) Boulware

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Robert MergesEvent Invitation2008 ROBERT MERGES, Wilson Sonsini Goodrich & Rosati Professor of Law and Technology, Director, Berkeley Center for Law & Technology, University of California School of Law – Boalt Hall
The Concept of Property in the Digital Age

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Commentator: Henry N. Garrana


Joel ReidenbergEvent Invitation2007 JOEL R. REIDENBERG, Professor of Law and Founding Director of the Center on Law and Information Policy, Fordham University School of Law
The Rule of Intellectual Property Law in the Internet Economy

Commentator: Jeff C. Dodd

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Arthur GajarsaEvent Invitation2006 THE HONORABLE ARTHUR J. GAJARSA, United States Court of Appeals for the Federal Circuit
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Commentator: Scott F. Partridge


Scott KieffEvent Invitation2005 F. SCOTT KIEFF, Professor of Law, Washington University in St. Louis-School of Law
Theory & Practice in Commercializing Innovation


Commentator: John D. Norris

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Jane GinsburgEvent Invitation2004 JANE C. GINSBURG, Morton L. Janklow Professor of Literary and Artistic Property Law, Columbia University School of Law School
The Right to Claim Authorship after DASTAR

Commentator: Paul E. Krieger

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