LIIBULLETIN-Patent

Li Second Family Ltd. Partnership v. Toshiba Corp., No. 99-1451, 2000 U.S. App. LEXIS 27921 (Fed. Cir. Nov. 8, 2000).

INEQUITABLE CONDUCT - PRIOR ART - ANTICIPATION - 35 U.S.C. § 102, 103, 120 - MATERIALITY - DECEPTIVE INTENT - AFFIRMATIVE MISREPRESENTATION - SEMICONDUCTOR TECHNOLOGY - GENEALOGY CHART

ISSUE & DISPOSITION

Issue(s)

1. Whether a party who, during patent prosecution, affirmatively claims the benefit of an earlier priority date under 35 U.S.C. § 120 and fails to disclose a PTO Board decision rejecting the benefit of that earlier date with respect to claims regarding the same technology in a related patent commits inequitable conduct.

2. Whether submission of a genealogy chart referencing a previously dismissed patent application constitutes sufficient written disclosure in a later patent application.

3. Whether an oral briefing of a patent examiner as to the perceived irrelevance of an earlier patent dismissal is sufficient disclosure of that dismissal.

Disposition

1. Probably. Nondisclosure and misrepresentation constitute inequitable conduct when there is intent to deceive the examiner and the information withheld would be material to an examiner's decision to issue the patent.

2. No. An applicant's submission of a genealogy chart with reference to a previously dismissed application, without specific mention of the PTO Board's decision, is insufficient disclosure to an examiner.

3. No. An applicant is responsible for ensuring that all business conducted before the PTO is documented in writing, including the substance of an earlier rejection.

SUMMARY

The Li Second Family limited partnership ("Li") owns U.S. Patent No. 4,916,513 (the '513 patent) and the related U.S. Patent No. 4,946,800 (the '800 patent), directed to the structure of and methods for making semiconductor devices. Both patents issued from applications that were continuations-in-part from a joint previous application and contained the limitation that the bottom of an "isolation groove" must be within 1.0 micron of a specific junction ("the 1.0 limitation") on the semiconductor body.

During prosecution of the '513 patent, Li attempted to overcome rejections for anticipation and obviousness under 35 U.S.C. §§ 102 and 103 by claiming the benefit of an earlier priority date for its patents under 35 U.S.C. § 120. Specifically, Li argued that the 1.0 limitation was supported by patents ancestral to the '513 patent. The examiner found that the earlier patents did not disclose the subject matter contained in the claims of the '513 patent and, therefore, denied the extension. Li appealed the decision to the PTO Board of Appeals which affirmed the examiner's findings and denied Li the benefit of the earlier priority date.

In subsequently prosecuting the '800 patent before a different examiner, Li continued to assert that it deserved the benefit of the earlier priority date for the 1.0 limitation. Li did not disclose the substance of the PTO Board's decision regarding the limitation to the examiner in writing, but referred to the '513 patent's application only through a genealogy chart of related applications that was included as a supplement. The examiner allowed the claims as the '800 patent, indicating that the priority date for the relevant technology was the earlier date under 35 U.S.C. § 120.

Li sued Toshiba Corp. ("Toshiba") in the US District Court for the Eastern District of Virginia for infringement of the '800 patent. Toshiba argued that the '800 patent was unenforceable due to Li's inequitable conduct in failing to disclose the PTO's decision to the examiner during prosecution of the '800 patent. Li alleged that its patent attorney discussed the PTO's decision with the examiner, but failed to make a written record of the substance of the discussion. The district court concluded that Li's failure to disclose or, alternatively, to make written record of the discussion with the examiner constituted inequitable conduct and ruled that the '800 patent was unenforceable. Li appealed.

Upon review for abuse of discretion, the Federal Circuit noted that a patent applicant is responsible for putting all prior, relevant communication with the examiner in writing. Additionally, the Court agreed with the district court that inclusion of a genealogy chart of related patent applications does not make an examiner sufficiently aware of the substance of a PTO's decision regarding one of those patents. Thus, the Federal Circuit found no clear error in the district court's findings that Li's failure to disclose the PTO's decision and instead affirmatively arguing the opposite constituted a "persistent course of nondisclosure and misrepresentation."

The Federal Circuit noted that nondisclosure and misrepresentation constitute inequitable conduct when there is intent to deceive the examiner and the information withheld is material. The Court found that information regarding the priority date of disclosed technology is critical to an examiner's decision to allow a patent claim. The facts supported the district court's finding that Li's arguing that it deserved the benefit of an earlier priority date revealed an intent to deceive the examiner. Thus, the Federal Circuit affirmed the district court's findings that the '800 patent is unenforceable for inequitable conduct by Li during prosecution of the patent.

Prepared by the liibulletin-patent Editorial Board.