Scott Daniels | July 14, 2011
Judge Marsha Pechman made some interesting comments last week in F5 Networks v. A10 Networks, 2011 U.S. Dist. LEXIS 73689 (W.D. Wash.), regarding the use of the PTO’s reexamination records to construe claims. F5 had sued A10 for infringing four patents. A10 defended, in part, by requesting reexamination of the F5 patents. The examiner, however, denied each of A10’s requests. A10 petitioned the PTO to overturn the denials, alleging that the examiner had “ignore[d] the prosecution history, applied[d] the wrong legal standard, mischaracterize[d] the cited art, and adopt[ed] a claim construction that is significantly narrower than the construction asserted by the Patent Owner.” That petition is now pending.
In the meantime, A10 argued that Judge Peckham should consider the examiner’s treatment of the reexamination requests in her construction of F5’s claims – presumably, A10 believes that F5 is pressing for a broader claim construction in the infringement case than was used by the examiner to deny the reexamination requests.
In response to A10’s argument, the Judge carefully analyzed the use of reexamination records in subsequent infringement cases. She indicated that comments in reexamination by both the patentee and the examiner may be treated as intrinsic evidence. Although “the majority of the cases where courts have admitted evidence of reexamination proceedings have concerned the statements or arguments of patentees which have then been used by district courts to construe disputed claims,” there are also “instances where the patent reexaminer’s construction has been considered part of the prosecution history.” She explained that “[b]ecause an examiner in reexamination can be considered one of ordinary skill in the art, his construction of the asserted claims carries significant weight.”
Here, however, “the findings of the reexaminer [are] in a patent proceeding which is not yet concluded.” Since A10’s petition of the denial of its reexamination requests is still pending, “the Court is faced with a reexamination record which is not complete.” Accordingly, the reexamination evidence which A10 has asked her to consider “is part of a pending reexamination process and thus not ripe for consideration or entitled to the same weight as those portions of the prosecution history which represent the final decision of the PTO” (emphasis added). Later in her actual analysis of the claims, she expressly declined to discuss the reexamination record.
It is not clear whether Judge Peckham would refuse to treat as intrinsic evidence any incomplete reexamination. Perhaps the examiner’s consideration of A10’s reexamination requests was a special case because F5 had not been required to comment.