Plant Genetic Systems v. Dekalb Genetics Corp.

• Citation: 315 F.3d 1335
• Decision Date: 13 January 2003
• Docket Number: No. 02-1011.,02-1011.
• Parties: PLANT GENETIC SYSTEMS, N.V. (now known as Aventis CropScience N.V.), Plaintiff-Appellant, and Biogen, Inc., Plaintiff, v. DEKALB GENETICS CORPORATION, Defendant-Appellee.
• Court: United States Courts of Appeals. United States Court of Appeals for the Federal Circuit

315 F.3d 1335

PLANT GENETIC SYSTEMS, N.V. (now known as Aventis CropScience N.V.), Plaintiff-Appellant, and Biogen, Inc., Plaintiff, v. DEKALB GENETICS CORPORATION, Defendant-Appellee.

No. 02-1011.

United States Court of Appeals, Federal Circuit.

DECIDED: January 13, 2003.

Rehearing and Rehearing En Banc Denied: February 20, 2003.

COPYRIGHT MATERIAL OMITTED

Eric H. Weisblatt, Burns, Doane, Swecker & Mathis, L.L.P., of Alexandria, VA, argued for plaintiff-appellant. With him on the brief were Susan J. Dadio, R. Danny Huntington, and Barbara Webb Walker.

John F. Lynch, Howrey Simon Arnold & White, LLP, of Houston, TX, argued for defendant-appellee. With him on the brief were Thomas A. Miller, and Richard L. Stanley. Of counsel on the brief Daniel T. Shvodian, Howrey Simon Arnold & White, LLP, of Menlo Park, CA. Of counsel was Hemant H. Kewalramani, Howrey Simon Arnold & White, LLP, of Houston, TX.

Before NEWMAN, MICHEL, and PROST, Circuit Judges.

MICHEL, Circuit Judge.

Plant Genetic Systems, N.V. ("PGS") appeals the September 7, 2001 decision of the United States District Court for the District of Connecticut, Plant Genetic Sys., N.V. v. DeKalb Genetics Corp., 175 F.Supp.2d 246 (D.Conn.2001), entering judgment for the accused infringer, DeKalb Genetics Corporation ("DeKalb"), on all counts of the complaint in this patent infringement suit. The case was tried to the bench for thirteen days. At the end of the trial, the district court concluded that claims 1-5 and 10-11 of PGS' patent, U.S. Pat. No. 5,561,236 ("the '236 patent"), were invalid for lack of enablement and that claims 8-9 and 12-15, the remaining asserted claims, were not infringed. Id. at 270. Because as to enablement, the defendant established a need for undue experimentation and as to non-infringement, that the properly construed claims did not cover the defendant's products, we affirm.

BACKGROUND

This case involves only one patent, the '236 patent, which claims a priority date of March 11, 1987. The patent issued on October 1, 1996 to inventors from PGS and Biogen Corporation and is directed to transgenic plant cells, plants, and seeds. DeKalb makes and sells transgenic corn seeds. PGS sued DeKalb for patent infringement the day the '236 patent issued.

The '236 patent and DeKalb's transgenic corn products relate to the herbicide-resistant characteristics of a plant or plant cell. Non-selective herbicides may indiscriminately kill most plants by blocking an essential biochemical process of these plants — metabolizing ammonia via the action of glutamine synthetase. Thus, these herbicides are also called glutamine synthetase inhibitors. Two structurally-related compounds, bialaphos and glufosinate, are such herbicides. It has been desirable to obtain food plants that are resistant to non-selective herbicides. Herbicide-resistant plants can grow in the presence of the herbicide that kills other unwanted plants or weeds.

The '236 patent teaches a plant cell, or a plant or seed containing such a cell, that is genetically engineered so that the cell can produce a protein that prevents herbicides such as bialaphos or glufosinate from blocking the function of glutamine synthetase. The mechanism of the engineering is to incorporate into the genome of the plant cell a gene (today called either the bar gene or the pat gene)¹, the protein product of which can inactivate a glutamine synthetase inhibitor.

The claims in issue are claims 1-5 and 8-15. Claims 1-5 and 10-11 include the cell, tissue and culture claims and are referred to, post, as "the cell claims." This group of claims all depends on claim 1, which reads:

A plant cell having a heterologous DNA stably integrated into its genome; said DNA comprising a heterologous DNA fragment encoding a protein having an acetyl transferase activity which inactivates a glutamine synthetase inhibitor in said cell.

Claims 8-9 and 12-15 are referred to by the parties and herein as the "plant and seed claims." Claim 8 is representative of this group of claims and reads:

A plant which consists of the cells of claim 1 and which is susceptible to infection and transformation by Agrobacterium and capable of regeneration thereafter.

A key issue of this case is the scope of both sets of the claims, i.e., what kind of plants or plant cells are covered by the claims. Flowering plants can be broadly categorized as monocotyledons ("monocots") and dicotyledons ("dicots"), depending on whether the initial development of the seed produces one leaf (monocot) or two leaves (dicot). In the '236 patent, all the working examples are dicots, for example, tomato, potato, and tobacco plants. However, the accused infringing product made and sold by DeKalb is corn — a monocot. Additionally, the scientific community was not able to transform monocots until after it first transformed dicots. Thus, it is disputed whether the cell claims of the '236 patent, which are agreed by the parties literally to cover all plant cells, were enabled for monocots on March 11, 1987. It is also disputed whether the plant and seed claims are correctly interpreted to exclude monocots, therefore leaving DeKalb's corn products outside the scope of these claims.

The district court, at its thirteen-day bench trial, heard evidence on various transformation techniques and the chronology of scientific progress regarding monocot transformation. Plant Genetic Sys., 175 F.Supp.2d at 255-64. At the end, the court found that despite the teachings of the specification, practicing stable gene transformation for monocot cells in 1987 required undue experimentation and, thus, the cell claims of the '236 patent were proven invalid for lack of enablement. Id. at 265.

The district court also construed the limitation "susceptible to infection and transformation by Agrobacterium and capable of regeneration" that was added to the plant and seed claims during prosecution to overcome the Examiner's rejection for non-enablement. The court held that a person skilled in the art at the time the parent application was filed would have understood the plant and seed claims to exclude monocots. Id. at 266-68. The court additionally considered trial testimony that no methodology existed as of the effective filing date of the '236 patent by which monocots could be infected and transformed by Agrobacterium to produce plants capable of regeneration. Id. at 268-69. The court viewed this testimony as further supporting its claim construction. Thus, the court held that DeKalb's transgenic corn products could not infringe the plant and seed claims because corn is indisputably a monocot. Id. at 269-70.

Both the invalidity and non-infringement holdings have been appealed.

DISCUSSION

Enablement is ultimately a question of law which this court reviews de novo. Durel Corp. v. Osram Sylvania Inc., 256 F.3d 1298, 1307 (Fed.Cir.2001). However, the factual findings underlying the legal conclusion are reviewed for clear error. PPG Indus., Inc. v. Guardian Indus. Corp., 75 F.3d 1558, 1564 (Fed.Cir. 1996). Claim constructions are reviewed de novo. Cybor Corp. v. FAS Techs., 138 F.3d 1448, 1454-55 (Fed.Cir.1998) (en banc).

I

PGS asks this court to reverse the district court's invalidity decision regarding claims 1-5 and 10-11 because, PGS asserts, the district court (A) failed to make any findings regarding the pioneering nature of the invention claimed in the '236 patent; (B) improperly shifted the burden of proof to the patentee to establish enablement; (C) failed to consider all of the relevant evidence; and (D) misused post-effective filing date work in its enablement determination. After considering each of PGS' arguments, for the reasons set forth below we conclude that the district court did not clearly err in its evidentiary findings and did not err in its conclusion that DeKalb had proven non-enablement by clear and convincing evidence.

A

PGS argues that the '236 patent is a pioneer patent and thereby entitled to a broad scope of coverage and lower standard of enablement. PGS asserts that, in failing to make any findings regarding the pioneering status of the invention of the '236 patent, the district court committed reversible error.

A patent application is required to "contain a written description of the invention, and of the manner and process of making and using it ... as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same." 35 U.S.C. § 112, ¶ 1 (2000). "To be enabling, the specification of the patent must teach those skilled in the art how to make and use the full scope of the claimed invention without `undue experimentation.'" Genentech Inc. v. Novo Nordisk A/S, 108 F.3d 1361, 1365 (Fed.Cir.1997) (quoting In re Wright, 999 F.2d 1557, 1561 (Fed.Cir. 1993)). Enablement is determined as of the effective filing date of the patent, In re Hogan, 559 F.2d 595, 604 (CCPA 1977), which, it is undisputed, is March 11, 1987.

We reject appellant's argument that the district court erred for making no finding on whether the claimed invention was "pioneering." Such a finding was unnecessary to the disposition of this case. We have previously affirmed a lack-of-enablement rejection by the United States Patent and Trademark Office ("PTO") without addressing the "pioneering" issue. In re Vaeck, 947 F.2d 488, 495-96 (Fed.Cir. 1991). Even in Hogan, on which PGS heavily relies, the Court of Customs and Patent Appeals stated, in addressing the Board of Patent Appeals' failure to consider the "pioneer" status of appellants' invention, that "[w]hether appellants' invention is of `pioneer' status is not before us and bears no relation to our decision herein, though such status may influence the decision required on remand." Hogan, 559 F.2d at 602 n. 10. Thus, we hold that the district court's failure here to make findings on the "pioneer" status of the '236 patent, without more, was not erroneous.

Further, even assuming ...