The Li Second Family Limited v. Toshiba

• Decision Date: 08 November 2000
• Citation: 231 F.3d 1373,56 USPQ2d 1681
• Parties: (Fed. Cir. 2000) THE LI SECOND FAMILY LIMITED PARTNERSHIP, Plaintiff-Appellant, v. TOSHIBA CORPORATION and TOSHIBA AMERICA ELECTRONIC COMPONENTS, INC., Defendants-Appellees. 99-1451 DECIDED:
• Court: U.S. Court of Appeals — Federal Circuit

Page 1373

231 F.3d 1373 (Fed. Cir. 2000)

THE LI SECOND FAMILY LIMITED PARTNERSHIP, Plaintiff-Appellant, v. TOSHIBA CORPORATION and TOSHIBA AMERICA ELECTRONIC COMPONENTS, INC., Defendants-Appellees.

99-1451

United States Court of Appeals for the Federal Circuit

DECIDED: November 8, 2000

Appealed from: U.S. District Court for the Eastern District of Virginia

Judge Leonie M. Brinkema

[Copyrighted Material Omitted] Rolf O. Stadheim, Stadheim & Grear, Ltd., of Chicago, Illinois, argued for plaintiff appellant. With him on the brief was Joseph A. Grear. Of counsel on the brief was Amy S. Owen, Miles & Stockbridge, of McLean, Virginia.

Arthur I. Neustadt, Oblon, Spivak, McClelland, Maier & Neustadt, P.C., of Arlington, Virginia, argued for defendants-appellees. With him on the brief was Carl E. Schlier. Of counsel on the brief were Ronald L. Yin and Stephen M. Everett, Limbach & Limbach L.L.P., of San Francisco, California.

Before PLAGER, CLEVENGER, and SCHALL, Circuit Judges.

PLAGER, Circuit Judge.

The Li Second Family Limited Partnership (Li) ¹ filed a patent infringement suit in the United States District Court for the Eastern District of Virginia against Toshiba Corporation and Toshiba America Electronic Components, Inc. (collectively Toshiba). Li alleged that Toshiba makes semiconductor devices using a process that infringes several claims of Li's U.S. Patent No. 4,946,800 (the '800 patent). Among its defenses, Toshiba alleged that the '800 patent is unenforceable because Li and his attorney engaged in inequitable conduct before the United States Patent and Trademark Office (PTO). After a bench trial on the issue, the district court agreed with Toshiba and concluded that the '800 patent is unenforceable due to inequitable conduct. Li Second Family Ltd. P'ship v. Toshiba Corp., No. 97-306-A (E.D. Va. May 19, 1999) (memorandum opinion and order). Because the district court did not abuse its discretion in holding the '800 patent unenforceable, we affirm.

BACKGROUND

1.

Li owns several patents, including the '800 patent and a related patent, U.S. Patent No. 4,916,513 (the '513 patent), in the area of semiconductor technology. Toshiba's inequitable conduct claim arises from Li's alleged failure to disclose to the examiner of the application that resulted in the '800 patent events that occurred during prosecution of the application that resulted in the '513 patent.

The '800 patent issued in 1990 from application Serial No. 05/386,102 (the '102 application), which was filed in 1973 as a continuation-in-part (CIP) of a now-abandoned 1971 application, Serial No. 05/154,300 (the '300 application). The '513 patent issued in 1990 from application Serial No. 05/838,758 (the '758 application), which was filed in 1977, also as a CIP of the '300 application. The '102 and '758 applications were assigned to different examiners at the PTO--the '102 application to Examiner Saba, and the '758 application to Examiner Larkins. The '300 application itself was a CIP of a 1968 application that issued in 1971 as U.S. Patent No. 3,585,714 (the '714 patent), which in turn was a CIP of a 1965 application that issued in 1969 as U.S. Patent No. 3,430,109 (the '109 patent).

The '800 patent is directed to a method for making a semiconductor device with isolation grooves used to separate regions of the device. More specifically, the '800 patent claims a method for making a semiconductor device by forming a semiconductor material substrate of one conductivity type (e.g., P-type); forming on the substrate a semiconductor material body of the opposite conductivity type (e.g., N-type), thus creating a PN junction; and forming an isolation groove in the body extending at least to the PN junction. All claims of the '800 patent include two important limitations: the bottom of the groove must be within 0.1 microns of the PN junction (the "0.1 micron" limitation), and the PN junction must meet the groove at a curved portion of the groove (the "rounding" limitation).

The '513 patent covers subject matter similar to that of the '800 patent, but its claims are directed to semiconductor structure rather than a method for making semiconductors. In the '758 application that resulted in the '513 patent, all originally filed claims, except claim 16, contained a limitation that the bottom of the groove must be within 1.0 micron of the PN junction (the "1.0 micron" limitation). Claim 16 contained the 0.1 micron limitation found in the claims of the '800 patent. Also, claim 8 as filed contained a limitation similar to the rounding limitation found in the claims of the '800 patent.

Prosecution of the '102 application, which resulted in the '800 patent, continued from its filing date in 1973 until February 10, 1977, when Examiner Saba suspended action on the application pending the outcome of an interference proceeding involving the '300 application. Prosecution of the '102 application did not resume until 1984. Meanwhile, prosecution of the '758 application proceeded without suspension.

2.

During prosecution of the '758 application, Examiner Larkins identified three prior art references--Peltzer, Murphy, and Sanders--that formed the basis for rejections under 35 U.S.C. 102 and 103. In response, Li attempted to eliminate the three references as prior art by asserting that, in accordance with 35 U.S.C. 120, his claims were entitled to the benefit of the filing date of either the application that resulted in the '714 patent or the application that resulted in the '109 patent. Examiner Larkins rejected Li's arguments, finding that the earlier patents did not disclose subject matter supporting the claims. In September 1979, Examiner Larkins issued a final rejection of all claims in the application.

Li appealed the final rejection to the PTO Board of Appeals (Board), ² which also rejected his attempt to establish an earlier priority date. In a June 17, 1981 decision, the Board found that Table 1, which appeared in the written descriptions of both the '109 and '714 patents, did not support the 1.0 micron limitation. Joint App. at 945. Even if Table 1 supported the 1.0 micron limitation, the parent--the '300 application--did not contain or incorporate by reference Table 1. Joint App. at 946. Upon Li's request for reconsideration, the Board explained that Table 1 showed distances both less than and greater than 1.0 micron and that neither the '714 patent nor the '300 application placed "particular criticality . . . upon the less than one micron feature." Joint App. at 960. Thus, the Board concluded that the claims of the '758 application were not entitled to the benefit of an earlier filing date, and that therefore Peltzer, Murphy, and Sanders were available as prior art references against the claims. Although the Board did not explicitly state that the earlier patents lacked support for the 0.1 micron limitation, it did so implicitly when it concluded that none of the claims, including claim 16 with the 0.1 micron limitation, were entitled to an earlier date. Furthermore, the reasoning behind the Board's decision applies equally to the 0.1 micron limitation and the 1.0 micron limitation--no prior patent or application placed any emphasis on the distance between the bottom of the groove and the PN junction.

The Board proceeded to sustain Examiner Larkins's 102 rejection of claim 1 as anticipated by Peltzer, which the Board found discloses the 1.0 micron feature. Although the Board did not sustain Examiner Larkins's 102 and 103 rejections of other claims, the Board entered a new ground of rejection: some claims were rejected under 103 as obvious in view of Peltzer, and some claims, including claim 16 with the 0.1 micron limitation, were rejected under 103 as obvious in view of Sanders. The Board explicitly found the 1.0 micron limitation would have been obvious in view of Peltzer's disclosure of a groove extending to the PN junction; this reasoning would also render the 0.1 micron limitation obvious. It appears that the Board rejected claim 16 over Sanders rather than Peltzer because Sanders disclosed the particular shape of the groove that was claimed in addition to the 0.1 micron feature. Original claim 8, which included the rounding limitation, was ultimately allowed and issued as claim 3 in the '513 patent.

3.

When prosecution of the '102 application resumed in 1984, the interference apparently having been discontinued, Li amended some of the claims to include limitations on the distance between the bottom of the groove and the PN junction. In rejecting these claims, Examiner Saba stated that several references, including Peltzer, inherently disclosed such distance limitations. Joint App. at 639, 727. Numerous times during prosecution, Li expressly indicated that the written descriptions of the '109 and '714 patents, and specifically Table 1, supported the distance limitations. Joint App. at 591-97, 599, 633. After Li amended the claims with distance limitations to include the 0.1 micron limitation, he continued to assert that his claims were entitled to either the 1965 filing date of the application for the '109 patent or the 1968 filing date of the application for the '714 patent, depending on the other limitations in each claim. Joint App. at 657-64, 767-68. These earlier priority dates were enough to overcome some of the cited references, including Peltzer, but not all of them. Li argued that the remaining prior art references did not sufficiently disclose the distance limitations. Joint App. at 746.

There is no written record of a disclosure to the PTO by Li of the Board's 1981 decision regarding priority dates in the '758 application. Li made reference to the '758 application only in a genealogy chart of related applications that he attached to the last supplemental amendment he filed. Joint App. at 777. Having accepted Li's argument that the claims of the '102 application were entitled to the benefit of an earlier filing date, Examiner...