Ex Parte Reexam Filings

By Jason Rantanen

In my Patent Law Year in Review talk this morning at the Wisconsin Bar Association’s Tenth Annual Door County Intellectual Property Law Academy, I touched briefly on ex parte reexamination filings.  With the heavy interest in inter partes reviews, ex parte reexam filings probably haven’t been on most people’s radar.  And until recently, data from the past year wasn’t available on the PTO’s website.   Recently, though, the PTO updated the data on ex parte reexamination filings (available here: http://www.uspto.gov/learning-and-resources/statistics/reexamination-information).  As the below figure shows, although there was a drop-off following the steep increase in the fee for filing ex parte reexamination and launch of inter partes review proceedings, parties are still filing about 50-100 requests for ex parte reexamination per quarter.  (For comparison, there are about 400-450 requests for inter partes review filed per quarter).

Ex Parte Reexam FIlings

I’d also like to give a shoutout for the assistance I received from calling the PTO’s ex parte reexamination hotline (571-272-7703).  It’s always great when a helpful voice is on the other end of the line.

20 thoughts on “Ex Parte Reexam Filings

  1. 6

    The above-hotlinked PTO ex parte* reexamination statistics seem to be lacking information badly needed by potential patent owner users or those facing being dragged into an ex parte reexamination by an adverse party. Please correct me if any of this data IS available anywhere:

    1. There is no breakdown between reexaminations filed by patent owners [to amend and/or add claims for assertion and obtain PTO blessing of claim distinctions over newly considered patent or publication prior art] versus reexaminations by adverse parties, in either filing or results. Nor the number of reexaminations filed anonymously.
    2. There is no data on the % of original claims surviving reexamination in these two very different kinds of reexaminations. Also, is there no data on the number of added claims?
    3. There is no distinction between reexamination results in software or business method related patents versus other technologies.
    4. There is not data on the % of reexaminations that are on patents that are in litigation.
    5. There is no data on how long the delay is averaging between CRU final reexamination decisions and PTAB appeal decisions thereon.
    6. There is no data on Fed. Cir. affirmance or reversal rates for PTAB decisions on ex parte reexamination appeals.

    *Also assuming that the CRU has now cleared out its entire former backlog of delayed old INTER PARTES reexamintion requests that were ended with the providing of IPRs.

  2. 5

    For those understandably upset about the high claim rejection rate in the IPRs which are instituted [not all IPR petitions are granted], note that the much more lucrative for the attorneys D.C. jury trial route is not exactly paved with patent owner roses these days either. E.g., the final* results just published on all the patent suits tried in 2013 in the presumed patent owner Valhalla of E.D. TX is 91% Defendant wins.

    Nor is the claim survival rate that great even in ex parte reexaminations filed by someone other than the patent owner.

    *that is final decisions after JNOVs and appeals

  3. 4

    The drop had less to do with the increased fee then it did the new AIA options opening to older patents on 9/16/12. Prior to that, ex parte reexams were necessary to challenge patents stemming from pre 11/29/99 patent applications. This is because inter partes patent reexamination was not possible for those patents, so, many went the ex parte route by necessity.

  4. 3

    “The result of the drop in ex parte reexams, and the elimination of inter partes reexams, has been that the Central Reexam Unit (CRU) at the PTO has not had much work to do, so the PTO just reassigned reissue processing to the CRU to give them something to work on.”

    If IPRs are to survive in some form, perhaps the CRU could be tasked with examining proposed new claims, with the petitioner allowed to chit-chat like in the former IP reexamination. Take these new claims off-line, and without the time requirements of an IPR.

    This simple change would simplify IPRs enormously, while providing office examination of new claims.

    1. 3.1

      Ned, a major reason for the drop in ex parte reexaminations vs IPRs is that they simply take too long for a patent that is in, or about to be in, litigation, even with the presumably reducing backlog of them. Not just because it is a two-step [CRU then PTAB] process rather than a one-step process. There is also the absence of any strict statutory time deadline for either step, the numbers of new claim that can be added, and other unknown delaying factors that need to be addressed. But allowing either patent owner or adverse party petitioners to “chit chat” off the written record in a reexam is not likely to help that problem, or be acceptable for patents that in many cases are in, or being groomed for, litigation.

      1. 3.1.1

        P.S. Another significant difference between reexaminations [handled by examiners assigned to the Central Reexamination Unit [CRU] and IPRs is that all IPRs are trials handled by Administrative Patent Judges [APJs], who are patent attorneys and are presumed to have legal expertise in the analysis of disputed and conflicting evidence and arguments. Hence it does not seem not logical to try to integrate the two proceedings in some way.


          Paul, as it is, almost no new claims are approved in IPRs due to the difficulty in proving a negative. The petitioner, as well, may have no interest in the new claims if they do not infringe them. Thus they may not have any incentive to conduct a search, etc.

          I would rather have an examiner take a look at new claims, with the burden to prove unpatentability on the PTO, rather than the other way ’round, as it turns out to be impossible to prove patentability.

          Sure it takes time — so we need to put some timelines on the PTO. They can do it if necessary. See the way they jump to it when we pay for Track I.

          Regarding the PTAB, currently they are not unbiased. I do not give a rats as about their skill level. They are out to get patents, and it is apparent for all to see.

          Also, even though the PTAB is currently the body that actually conducts IPRs, it is the Director, a political appointee, a minion of the president who is ultimately political, that actually calls the shots. There is nothing in the statute or rules to prevent him or her from doing so.

          Kinda reminds me of those show trials during the French revolution, where the accused received a “fair” trial. The burden was on the accused to prove innocence. The mob cheered and groaned as evidence was produced. And sitting there, next to the court of three judges, was Robespierre.


            Ned, if those unfounded allegations [with insults to APJ integrity and ignoring their strong civil service independence protection] were true, there would be a massive rate of Fed. Cir. reversals of PTAB IPR decisions, rather than the actual massive rate of IPR decision affirmances – much higher than the Fed. Cir. affirmance rate of jury trial decisions.
            Those who have lost big personal lawsuit billing opportunities on patents never properly examined as applications over missed more relevant prior art are hardly unbiased commentators on the IPR system.


              If there was anyone on these boards more biased as to the IPR’s in an anti-patent holder sense then Paul, I would be shocked.

              This “those who have” then comes across as a duplicitous false flag type of “logic.”

              Just don’t buy it, Paul – least wise from you.

  5. 2


    Is any data on whether or not at the present lower rate of total inter partes reexamination filings a higher percentage are now being filed by patent owners vis a vis adverse parties [including anonymous requests]?

    Or information on the % of inter partes reexaminations on patents that are in litigation?

  6. 1

    Not surprising, ex parte reexamination is not a particularly good way to challenge the validity of the patent as the challenger has no right to participate after the filing of its request.

    Ex parte reexamination has historically been a lot cheaper than inter partes alternatives, which explained some of its popularity in the past. But now with the fee hike, the only benefit of ex parte reexam (if one can consider it one) is that one can be filed anonymously, which generally isn’t enough to justify the cost.

    The result of the drop in ex parte reexams, and the elimination of inter partes reexams, has been that the Central Reexam Unit (CRU) at the PTO has not had much work to do, so the PTO just reassigned reissue processing to the CRU to give them something to work on.

    1. 1.1

      Fully agree, thanks.
      But ex parte reexamination is a useful pre-suit tool for some patent owners, along with the AIA “Supplemental Examination” version of it, and/or reissues [which the CRU should now handle faster and better than reissue-inexperienced examiners]. That is, being able to amend original claims and adding lots of new claims for assertions and obtaining PTO blessing of claim distinctions over newly considered patent or publication prior art completely ex parte.
      This has become far more potentially important since the prior assumption that claim validity will only be effectively challenged in the very small percentage of patent suits that are fought all the way through trial and appeal is no longer a valid assumption in view of thousands of IPRs filed by savvy defendants.
      As for anonymous reexaminations, once the subject patent is sued on, a party to the litigation should be allowed to find out in discovery if the reexam was by or for the other party or its privy. However, I know of one case in which the D.C. judge refused to grant such a discovery request. A third party subpoena to the reexam request submitter can be avoided by having someone in Ontario Canada file the anonymous reexam request

      1. 1.1.1

        Paul: As for anonymous reexaminations, once the subject patent is sued on, a party to the litigation should be allowed to find out in discovery if the reexam was by or for the other party or its privy.



          Ned, at least two reasons I can think of offhand:
          1. potential violation of a protective order preventing use of secret information [such as new product plans] obtained by litigation discovery in making claim amendments in the reexamination, and
          2. the requirement that some D.C. judges are quite strict about to promptly disclose any and all activities by the parties related to the suit. “Public Pair” access to papers filed in reexaminations and Office Actions thereon can be considerably time delayed even if the “anonymous” reexamination is known about to both parties.


            But we are talking here about the petition and the petitioner – they are anonymous. The patent owner must conduct the actual proceedings in the reexamination. So I don’t understand how your first point is relevant.

            The reexamination self should be brought to the attention of the court. But I don’t understand why the identity of the petitioner is relevant to anything – except for estoppel purposes.


            Aah. Your first point seems to assume that the patent owner or the accused infringer may have used patents and printed publications that were subject to a protective order in an anonymous filing.

            Something seems very or wrong with this statement because patents and printed publications should not be the highly confidential information of a party and designating them as such in the first place seems to be a violation of public policy.

            Be that as it may, I think any motion in court should demonstrate that the patent and printed publications relied upon in the petition must have come from a violation of the protective order.


            The anonymous nature of the ex parte reexamination is part of the statutory scheme, and a clear distinction over other forms of post-grant relief. I don’t think the anonymity ground is relied upon by that many filers these days, but it seems like if you wanted to pierce the anonymity, you’d need a good justification.

            Neither of the two rationales in this post make much sense.

            Regarding the first rationale, it’s hard to imagine how a protective order violation could stem from an ex parte reexamination filing. The ex parte reexam request is public, and the only prior art references you can rely upon are patents and printed publications, both of which must be publicly accessible. I do not know how confidential “new product plans” of the plaintiff, the example you give, would have any relevance to an ex parte reexam request attacking an existing patent that issued before those plans came into existence.
            But certainly if a litigant filed an anonymous ex parte reexam request and gratuitously disclosed confidential information in violation of a protective order, I suppose in that case, a district court may have cause to allow the plaintiff to seek discovery on the identity of the filer. But I think a district court would almost certainly require a threshold showing that something in the request raises a possibility of a protective order violation, before it would allow any such discovery.

            On the second rationale, that doesn’t make sense either. District courts often impose a requirement that parties inform the court of other related proceedings involving the patent. But that obligation extends to the plaintiff also, who would itself be obligated to bring the reexam to the Court’s attention once it was served with it. And the defendant could also bring it to the Court’s attention, saying it found it when looking at the file history through PAIR. The requirement of disclosure of concurrent proceedings does not necessarily require a party to disclose who originally filed the reexam.

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