Expert’s Violation of Prosecution Bar Warrants His Disqualification

My book on ethical issues in patent litigation (shameless plug there!) spends a significant amount of time on prosecution bars.  They create more issues than most people think, and deserve careful attention by counsel.  Perhaps because of the difficulty of policing violations, there are not many decisions addressing what to do if there is a violation.

Magistrate Judge Grewal out in the Northern District of California recently faced that.  The defendants learned that the plaintiff’s expert had prosecuted a patent application in a “barred” area.  The magistrate ordered the expert to return the information he had received during the suit, to not use any information he remembered for any purpose, and excluded the expert as a witness in the case.  The magistrate, however, pointed out that the plaintiff could retain another expert.  It did not award any costs.  Avago Technologies Fiber IP (Singapore) PTE. Ltd. v. IPtronics Inc., 5-10-cv-02863 (N.D. Cal. June 11, 2015) (Grewal, M.J.).  (Opinion here.)

There are lessons all around.  For experts, it is to understand what these bars mean.  For counsel, it is to ensure that experts understand what those bars mean.  For everyone, it means to use reasonable care to ensure compliance — by your team as well as the other side’s.

About David

Professor of Law, Mercer University School of Law. Formerly Of Counsel, Taylor English Duma, LLP and in 2012-13, judicial clerk to Chief Judge Rader.

10 thoughts on “Expert’s Violation of Prosecution Bar Warrants His Disqualification

  1. 2

    OT, but perhaps you can run a post on a particular “ethical” dilemma in patent law that does not seem to garner enough attention: asking the judiciary to assume the role of the legislator.

    Unfortunately behind a paywall, Ned Heller recently posted a link to a stern warning given by Judge Kathleen O’Malley.

    Since so much angst revolves around 101 and the judicial mess thereof, perhaps your views on the O’Malley text would be worthwhile…

    1. 2.1

      I don’t have the text. Don’t get me started on how the Supremes, without talking about the text of the statute, have forced the CAFC to engage in judicial law-making. It’s awful.

      1. 2.1.1

        David, if the Federal Circuit did not have a monopoly on patent law at the circuit court level, it would not have to power to change the law.

        The old system was provided a much better systems for developing patent law as the circuit courts could debate issues, not impose their will on the country. Monopolies, even in law, are inherently a bad choice.



          You do realize that this is statutory law we are talking about right?

          Your blindness and adoration of common law is a bug, not a feature.


            What “you” are talking about and what” we” are talking about are not the same thing, anon.

            The only way a court can “legislate” is if it has a monopoly. Now whether this is not following the statutes, not following the Supreme Court or well established precedents is simply a “design choice.” You might they do not follow the statutes. I complain about this and about their not following the Supreme Court as well.



              There is NO “we” in placing the Supreme Court in the legislative branch of the government in relation to the critical question of separation of powers and allocation of authority to write the statutory law that is patent law.

              Like most other points that you find inconvenient, you just clench your eyes tight when your inconsistencies scream out.

              link to


              That’s simply not true that a court can’t legislate unless it has a monopoly. Happens a lot among the circuits and the supremes don’t police everything/don’t want to police everything.

              Sadly, too many people treat the patent act like the Sherman Act, as a license by Congress to make up the law. It’s nothing like that, and hasn’t been since 1952.


                Did you mean a license by the Court to make up the law, Prof. Hricik?

                It is even more sad when people who should know better continue to try to re-write history and pretend that 1952 was only a codification of intervening judge-made law and seek to ignore the fact of the matter that Congress was reacting against an anti-patent judicial body that was making a mess of the patent system.

                History does indeed repeat.

Comments are closed.