The Role of an Patent Procedure Expert in Patent Litigation

Steve Kunin

What follows is the final segment of my interview with Steven Kunin, the former Deputy Commissioner for Patents for Patent Examination Policy and current partner at Oblon Spivak. In part 1 of our interview we discussed the Federal Circuit, de novo review and how to manage patent examination policy when the Supreme Court refuses to allow bright line rules. In part 2 we discussed administrative patent trials brought into being by the America Invents Act (AIA). In this final segment we discuss the role of a patent expert and particularly focus on inequitable conduct since Therasense.

Without further ado, what follows is the interview finale.

QUINN: Let’s shift gears a little. I know one of the reasons that we wanted to sit down and talk today is to talk about the role of an expert witness in patent cases post-Therasense.  So maybe we could just jump right in with your initial thoughts and then we can go from there.

KUNIN: I think there is a significant misunderstanding  of the value of patent office practice expert witnesses in patent litigation.  Some people have the misperception that all of the work of patent office practice experts has been in support of or defending against inequitable conduct allegations in the federal courts .  Some believe that as a result of the Therasense case patent office practice experts have no longer any role to serve.  Certainly a patent office practice expert cannot testify as an expert on the law; that is the province of the judge.  But there are lots of aspects of PTO practice and procedure, which are a black box to both juries and judges in  patent litigations.  In those cases, a patent office practice expert will serve a valuable role to help navigate the judge and jury through the patent examination process and the intricacies of what happened through the lens of the applicable practices and procedures governing the process.

QUINN: Well, let me just stop you there before we go to much further and address that. I think there are a lot of things that are a black box, but is it even true that post Therasense the role of the expert has been diminished?  It seems to me that inequitable conduct still gets alleged in virtually every case, correct?

KUNIN: That’s true.  There remains a role for patent office practice experts post-Therasense.  The patent office practice can rely of the opinions of a technical expert.   For an issue like inequitable conduct, questions of non-cumulativeness and materiality are treated first by the technical expert, then are translated by the patent office practice expert into the aspects of patent office rules and procedures.  The patent office expert brings together all the various elements that make up the duty of candor and good faith, including the duty of disclosure owed to the PTO.

QUINN: I assume you’ve probably had situations where you’ve testified that there has been inequitable conduct and I’m sure there are times where you’ve testified that there hasn’t been inequitable conduct.  How do you approach both procedurally or mechanically on your end? What is it that you contribute in terms of the piece of the puzzle that really will be the most helpful for the judge or jury?

KUNIN: Well, of course now that we have the “but-for” materiality standard under Therasense, the question of materiality is, based upon the preponderance of the evidence whether an original patent claim, given a broadest reasonable interpretation, would have been issued based upon the undisclosed information taking into consideration any patent owner rebuttal evidence.  Materiality is not an invalidity standard proven by clear and convincing evidence.  But-for materiality is very much akin to what is applied in USPTO proceedings, whether it’s done in a patentability determination in a reexamination or an administrative trial or even an appeal from an examiner’s final rejection.  So typically the technical expert is only going to be able to address the issues from a person of ordinary skill in the art perspective.  This includes whether under a given claim interpretation is a reference anticipatory or not.  If there’s a question of obviousness under KSR the analysis of the technical expert would include whether there would there have been apparent reason why a person ordinarily skilled in the art would have found the claimed invention to have been obvious.  But typically the technical expert has no experience whatsoever in dealing with patent examiners and  how examination is conducted in the PTO.  So how would a technical expert appreciate what the PTO would or would not do with the evidence in terms of deciding whether to allow a claim be issued?  That is where the patent office expert comes in.


QUINN: All right. One more question on inequitable conduct.  I know a number of people thought that inequitable conduct was going to go away when the standard changed to “but-for.”  I guess except for intentional fraud, right?

KUNIN: You mean affirmative acts of egregious misconduct which are material per se or as a matter of law.

QUINN: Yes, apply the “but-for” materiality standard unless there is egregious misconduct.  So many thought this was going to essentially wipe this whole area away.  But that isn’t really what’s happened, is it?

KUNIN: No.  What you find in litigation is that the technical expert is working from the mindset of trying to establish that claims of a patent are invalid, or on the flip side why the claims of the patent are not invalid.  And their focus really is typically on the higher level test for proving claim invalidity.  And therefore because they are applying a higher level invalidity standard and the preponderance of the evidence “but-for” materiality standard is a lower standard, you still get to the same place because it’s a lower burden of proof to establish “but-for” materiality.  In fact, in one of the post-Therasense cases decided by the Federal Circuit, the Honda or  Calcar case found that the “but-for”materiality standard was proven by proving claim invalidity.

QUINN: I think that’s a surprise to a lot of people who haven’t followed the development of this area post Therasense.  It is true that Therasense changed the standard but it didn’t change the reality that the defense raises inequitable conduct all the time and the reality that inequitable conduct continues to be found in at least some cases.

KUNIN: Yes.  In fact, there are some recent Federal Circuit cases such as Intellect Wireless v. HTC that has found inequitable conduct and in particular would reach back to the old Rohm & Hass case with respect to providing more of the contours of what constitutes affirmative acts of egregious misconduct.

QUINN: Okay.  Now, let’s circle back to where I interrupted you – back to the black box discussion.  There are a lot of other areas where patent practice is a black box, as you called it. How do you as an expert convey to a judge or a jury our Byzantine process so that they can understand it?

KUNIN: Well, that’s always a challenge because you want to be able to explain things in laymen terms so that they can appreciate why things happen at the PTO and how things work within the PTO.  So therefore, if you resort to legal jargon such as discussing that there was a restriction between independent and distinct inventions or an election of species you’ve lost them right from the git-go.

QUINN: You lose your wife and kid when you talk like that, too.

KUNIN: That’s right.  They  will leave the room.

QUINN: Right, right.  It works 100% of the time.

KUNIN: That’s right.

QUINN: Now I also suspect that when you’re going down that path, I mean the term is “restriction” and how do you explain it so that you get the point across but then haven’t really just opened up really a red herring on cross-examination?

KUNIN: It’s really plain and simple.  Because if you stay within the scope of your expertise, namely as a patent office practice expert who references specific provisions of the MPEP, or more particularly the PTO rules of practice, to support your opinions then you don’t need to worry about cross-examination because the bases for your opinions can be found within PTO published policy, practice and procedure.  You don’t need to use the technical language within our profession to bring across concepts that even a lay jury can understand.  Using examples brings home the concepts to them to makePTO practice and procedure comprehensible.

QUINN: So what other kinds of issues typically come up in a case that a patent expert can assist with?

KUNIN: Well, I’ll give you an example with respect to obviousness type double patenting and the safe harbor provisions of Section 121.  To be eligible for the safe harbor consonance must be maintained with respect to the claims in a later filed divisional application even when filed as a result of restriction requirement.

QUINN: Right.

KUNIN: — In the litigation of a divisional patent the question many times arises about whether the safe harbor provision of 121 applies such that obviousness type double patenting can’t be applied.

QUINN: Right.

KUNIN: It is part of PTO practice and procedure to look at the different groupings of claims in the restriction requirement, then determine whether the elected invention in the application where the restriction requirement was made was reclaimed in a divisional application resulting in consonance being lost and the safe harbor provision beinglost as well.  Obvious type double patenting could then apply.

QUINN: And that is just a nightmare type of a situation as well.  In the Bristol Myers case they had the great-great grandchild patents and they had gone all along the way just willingly acquiescing the restriction after restriction, which makes sense because you’re realistically never going to win a petition or restriction.

KUNIN: And you don’t have to challenge the restriction requirement for the safe harbor to apply.

QUINN: Right.  So they just kept acquiescing and then they found that consonance was lost along the way because the restrictions that they were getting were inconsistent with each other.  That struck me as an unfair scenario.  Maybe it’s a highly technical double patenting issue and you don’t necessarily see that all that often, but I think people would be really surprised because many times patent applications are pending for five years or more, ten years is not uncommon to have a file open at the patent office. The procedural machinations that these cases go through can be quite bizarre.

KUNIN: There’s no question about it.  When you review file histories as a patent office practice expert it’s an eye-opening experience because sometimes it’s almost inexplicable as to what happened and how it could possibly have happened.  And that’s what leads to some of the litigation because of the kinds of things that happen in these cases.  It demonstrates why there’s still a place for a patent office practice expert in patent litigations due to the eccentricities of the practice and procedure that lead to peculiar results.  An expert is needed to explain how and why these situations happen in the PTO.

QUINN: Yeah, no, I can imagine.  I had a case, and this is a few years ago, where we responded timely twice and it went abandoned.  I won’t bore you with the details, but I wound up calling the ombudsman and when I got through the whole story the ombudsman said, “So you responded timely twice and the case is now abandoned?”  Yes.  “I can help with that.”

KUNIN: Well, I think that really answers the question as to why you need a patent office practice expert in litigation because it can be so difficult to navigate and explain the patent examination process.  Sometimes you shake your head in terms of how one thing happened after another that led to a particular result that is defies how proper PTO practice and procedure is defined in the rules of practice and the MPEP.

QUINN: Right.

KUNIN: And then you have to figure out, as you point out, what are the various machinations at work in terms of how things can go down different paths during patent examination depending upon a given set of circumstances.

QUINN: Right.


KUNIN: I’ve been involved with a number of cases that have to do with trying to figure out, for example, what information the examiner considered or did not consider.  This can go down a very complex path.  For example, what if you have an examiner who does an automated search of non-patent literature?  And the examiner is supposed to print the search logic and the search results and include it in the file history.  Suppose you see the search logic and the search results and included in the search results are certain documents, which are identified but there’s only an abstract of the results printed.  You look at the examiner’s notice of references cited and let’s assume that maybe 10% of the ones that are on that search results print out list are listed in the notice of references cited.  The search notes section of the file wrapper is not annotated.  Did the examiner consider the ones that are not in the notice of references cited?  There’s a printout there and there’s an identification of certain technical literature and at least an abstract.  Did the examiner read them or not?

QUINN: Right.  And isn’t that to some extent what the i4i v. Microsoft case was about whether there should be different standards for invalidity with respect to what the examiners consider versus what the examiner hasn’t considered. But how will we even know because when you’re doing a search or you’re reviewing a search you look at everything to at least decide whether and to what extent you are going to consider the reference.  But you considered it to at least decide that it wasn’t as relevant as something else.

KUNIN: There are all of these different types of issues that arise in patent litigation.  Some issues are straightforward to resolve when, for example, the examiner initials next to a particular document indicating that it was reviewed, even though it doesn’t appear on the notice of references cited. Or the examiner lines through the document on the search results.  But what if the examiner does nothing?  Consider problem when the examiner puts a patent classification in the search box of the electronic file wrapper and you ask yourself did the examiner look at every document in that classification or did the examiner only look at those documents that were related to a full text search based on a limited search query?  Despite the excellent guidance that the PTO provides in the MPEP with respect to how examiners are to annotate their search notes I’ve reviewed hundreds and hundreds of file histories and I can tell you that it’s more likely than not that the examiner has not annotated the search notes in the way the MPEP 719.05 instructs them to do.


KUNIN: There is a presumption that the file history is complete and therefore it should be available to be relied on in a litigation.  But then you get into these anomalies where the PTO says do this and do that but the file history doesn’t show it’s been done.  Did the examiner actually do it and fail to annotate or did the examiner not do it and that’s why it wasn’t annotated.

QUINN: It’s hard to know how you would come out on a question like that.  I mean you’d probably have to take the totality of the file history into account and maybe even look at some of the other cases that the examiner handled to see how they operate.  I mean that’s one of the frustrating things I think is the patent office gets bigger and bigger and bigger and it seems to be a whole lot of lack of uniformity at the patent office.  And I don’t know—I mean I suppose I can guess why that is.  I tell the students when I teach the patent bar courses that you printed out the MPEP it would be as big as a Chicago area phone book in size.  Despite that size there’s still not a simple direct answer to many questions that you would think should be addressed.

KUNIN: People like Drew Hirshfeld and Rob Clarke at the USPTO say that their plan is to update the MPEP on a more regular basis.  Maybe even issue revisions multiple times in a given year.  Historically you wait a whole year before you got a new edition or revision of the MPEP and then by the time it was published it was not up to date with changes in the case law.

QUINN: Right.  And one of the problems we have now and with the patent bar is the—and the exam is much more up—I mean it’s up to date, it was just updated January 2014 with all kinds of new things.  For example the Patent Law Treaty Implementation Act is now tested, but one thing that is frustrating for students is that Chapter 1200, which deals with appeals, hasn’t been updated to incorporate the update to the Rules that became effective in November of 2011.

KUNIN: Remember that Chapter 2000 of the MPEP on the Duty of Disclosure hasn’t been updated since 2004.

QUINN: Oh, wow.  I guess I didn’t realize that.

KUNIN: Yes it has not been updated in ten years.

QUINN: Wow.  So they don’t even talk about Therasense in there.

KUNIN: No, Chapter 2000 covers none of the post 2004 case law. Prior to Therasense every one of five different materiality standards were applicable.  The PTO proposed a post Therasense revision of rule 56, which has not been finalized.

QUINN: Right, even the intent standard has changed eliminating the gross negligence should have known standard.

KUNIN: Which if you go back to 1989 was eliminated by the Federal Circuit sitting en banc.—

QUINN: Contradicts Kingstown, right?

KUNIN: —the Kingstown  decision held that gross negligence is not the appropriate standard for intent.  But it took us almost up to Therasense for a return to the actual knowledge of materiality standard as an element in proving intent to deceive the PTO.  And then of course what was added by Star Scientific is the intent test that the single most reasonable inference drawn from all inferences must be intent to deceive the PTO.  That’s probably the one very significant difference that we see in the law of inequitable conduct now.

QUINN: And it makes some sense since you’re dealing with intent on some level you’re never going to know for sure.  I mean some cases you will because there will be a memo or an email or something somewhere that we could never turn this over.

KUNIN: Some courts say you have to have a “smoking gun” to prove intent under current law.  I’m not convinced that that’s the standard even under the single most reasonable inference test, but it’s interesting to see that in some judge’s mind you nearly have to have a “smoking gun” to succeed in proving intent to deceive.

QUINN: Well, I can’t say I disagree with that either just simply because that would be pro patentee, which seems to be in such short supply any more.  Whether it be in the Executive Branch or in Congress or in the Judiciary. Well, thank you very much, Steve, I appreciate you taking time to talk to me.

KUNIN: Always a pleasure, Gene.


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Join the Discussion

2 comments so far.

  • [Avatar for Steve]
    March 20, 2014 07:49 pm

    Thanks for the great interview guys.

  • [Avatar for Lisa]
    March 20, 2014 02:04 pm

    Lot of useful information. Thanks!