Fairchild Semiconductor Corp. and Fairchild (Taiwan) Corp.'s  (collectively, "Fairchild") moved in limine to preclude any reference to any pending reexamination proceeding or any completed reexamination proceeding of any asserted patent. Defendant Power Integrations, Inc. ("PI") asserted that the fact the PTO finally rejected all asserted claims of the patent "is central to the 'specific intent' element (or the lack thereof) of Fairchild's inducement claim" and also negated Fairchild's proof of intent with respect to willful infringement.

The district court disagreed with PI. Noting that the Federal Circuit "has often warned of the limited value of actions by the PTO when used for" the purpose of "negating the requisite intent for inducement," the district court stated that the "[t]he pending reexamination of Fairchild's asserted patent is not final, as Fairchild has appellate rights. Pursuant to Federal Rule of Evidence 403, the limited probative value of evidence of the reexamination' is substantially outweighed by the risk of unfair prejudice to Fairchild, especially the risk of confusion and the need to educate jurors on administrative proceedings governed by different standards and on the potential for reversal of the PTO on appeal." 

The district court also addressed PI's other patent-in-suit, which had successfully completed re-examination. "Evidence and argument relating to the completed reexamination of PI's '366 patent also has minimal probative value -- the '366 patent has been valid and presumed valid since its issuance, and remains so following reexamination -- which would be substantially outweighed by the risk of unfair prejudice to Fairchild if admitted, as jurors could mistakenly apply a higher burden to a challenge to the validity of claims that have withstood reexamination."

Accordingly, the district court determined that "[w]hile there shall be no reference to "reexamination," evidence (including prior art) used during a reexamination is not inadmissible solely due to its use or even creation during a reexamination, provided that general terminology (e.g., "prosecution history") is used and necessary redactions are made. In particular, the parties will be permitted to prove and argue that certain evidence was (or was not) reviewed by the PTO, but will not be permitted to prove or argue how many times such evidence was reviewed by the PTO."

Fairchild Semiconductor Corporation v. Power Integrations, Inc., Case No. 12-540-LPS (D. Del. Apr. 23, 2015)