Should I Request Ex Parte or Inter Partes Reexamination?

Scott Daniels | February 14, 2011

Each quarter, the PTO compiles its reexamination statistics showing the number of ex parte and inter partes reexamination requests filed, the number of cases where the claims are confirmed, amended or canceled, etc.  In recent years, the total number of reexamination requests has trended slightly upwards, with inter partes requests accounting for 25 to 35 % of the total.  In the last three months of 2010 (here, here), the inter partes request portion of the total was at the upper end of that range.

What interests us, though, is the fact that for those patents where the requestor has the option between ex parte and inter partes reexamination, ex parte reexamination is chosen at least 50% of the time. (Where the patent issues from an application filed before November 29, 1999, the requestor’s only choice is ex parte reexamination (see Cooper v. Dudas, 87 USPQ2d 1705, 1706 (Fed. Cir. 2008)).  One might expect that inter partes reexamination, despite its hefty PTO filing fee of $8,800.00, would the overwhelming choice.  Why is ex parte reexamination, with essentially no right for the requestor to participate, chosen so often?

Unfortunately, our answer is not based on a clean, specific statistical analysis, but on a subjective assessment of numerous reexamination decisions, plus a good amount of anecdotal evidence.   In most cases, we believe that inter partes reexamination is preferable because of the opportunity for the requestor to participate throughout the proceeding, even through an appeal to the PTO Board or the CAFC.  The patents in reexamination are typically of great commercial value, and the patentee acts accordingly, going “all out” to present the type of exhaustive legal argument and expert evidence normally associated with litigation.  The deck is stacked against the requestor unless it is permitted to reply to the patentee.  Our conclusion in favor of inter partes requests, at least where anonymity is not an issue, is supported by the behavior of the most frequent requestors.  For instance, when Apple is sued, it commonly requests inter partes reexamination against each of the patents-in-suit.

On the other hand, in an inter partes request, the real party in interest must identify itself, whereas in ex parte reexamination the request may be filed anonymously.  37 C.F.R. § 1.915(b)(8).  In some cases, a company’s requesting reexamination is equivalent to its hoisting a red flag announcing its concerns that it infringes the patent.  In those cases, the appeal of anonymity may override the privilege of replying to the patentee’s arguments.  More often, however, where the patentee has already sued or the patentee will readily infer the requestor’s identity, inter partes reexamination makes more sense.

Why then the large number of ex parte requests?  Requestors are frequently deterred from inter partes reexamination because, should the validity of the patents be confirmed in the reexamination, the requestor and “its privies” will be estopped from asserting in District Court any defense that the requestor “raised or could have raised during the inter partes reexamination proceedings.”  35 U.S.C. § 315(c).  Since there is no corresponding estoppel for ex parte reexamination, requestors hope to repeat their reexamination argument against the validity in a later District Court case.  We do not think that this is a realistic hope – we strongly expect that judges will be extremely skeptical of arguments rejected by the PTO, even under the lower “preponderance of the evidence” standard of proof.

Other factors tilt the choice in favor of inter partes reexamination.  For instance, the patentee may interview examiner in ex parte reexamination, but interviews are quite limited in inter partes reexamination. 

Still other factors may tilt the choice somewhat in favor of ex parte reexamination.  For instance, an accused infringer that loses its prior art invalidity argument in District Court cannot file a new inter partes request or even “maintain” an inter partes request already filed.  35 U.S.C. § 317(b). 

The relative likelihood of a court staying litigation in a parallel District Court case should not affect the choice between ex parte and inter partes reexamination.  For every court decision where a stay is refused because there is no estoppel in ex parte reexamination, there is another court decision where a stay is refused because inter partes reexamination takes so much longer than ex parte reexamination.     

But, as always, the facts of each case must be considered in their own light…

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