SnowBall archive



Information Systems For Biotechnology 
National Biological Impact Assessment Program
March 1999
News For The Agricultural And Environmental Biotechnology Community 
Bacillus thuringiensis (Bt) continues to breed controversy. Outside the United
States, January was a turbulent time for transgenic plants engineered to
express Bt toxins. Monsanto literally drew fire in India for its tests of
transgenic cotton when annoyed farmers torched test plots. In Ireland,
protesters reportedly sabotaged fields of genetically engineered potatoes,
while French farmers staged a raid on a cache of genetically modified
seeds. On
a more positive note, the House of Lords European Communities Committee gave a
green light for large-scale trials of genetically engineered crops, providing
that proper regulatory safeguards were in place. Despite this announcement,
there is still some resistance to the farming of herbicide tolerant and insect
resistant crops in the United Kingdom.
Meanwhile, the U.S. saw a number of skirmishes in the Bt patent wars in 1998.
Surprisingly, three courts decided that patents assigned to Mycogen
Corporation, Monsanto Company, and Novartis Seeds, Inc. are invalid.
Courting Disaster 
The first of these disarming decisions occurred in February 1998, when a jury
in a Delaware U.S. District Court decided that two Bt patents assigned to
Mycogen Plant Science, Inc. are not valid. The suit began in October 1996 when
Mycogen claimed that Monsanto, Delta & Pine Land Co., and DeKalb Genetics
infringed Mycogenís patents by marketing genetically engineered cotton,
potatoes, and corn. The Mycogen patents claim methods for making synthetic Bt
genes and using them to develop insect resistant plants and seeds.
According to
Mycogen's president, the patent claims at issue are merely a subset of broader
claims contained in another patent that covers the process of making bacterial
genes more plant-like. His statement might have referred to U.S. Patent No.
5,380,831, which is discussed below.
A June trial concerned Monsantoís patent infringement claims against the
Agrigenetics (now Mycogen) and the former Ciba-Geigy Seeds (now Novartis
Seeds). The patent in dispute, U.S. Patent No. 5,550,365, names David A.
Fischhoff and Frederick J. Perlak as inventors. The patent contains claims to
methods of modifying Bt toxin genes to achieve higher levels of expression in
transgenic plants. The jury of a U.S. District Court in Delaware decided that,
although Agrigenetics and Ciba-Geigy Seeds had infringed Monsanto's method for
making the synthetic Bt genes, the infringement was excused, which effectively
neutralized the patent.
Finally, in November, a Delaware federal jury decided that a Novartis Seeds
patent was invalid and not infringed by Monsanto and DeKalb Genetics, Inc.
lawsuit concerned U.S. Patent No. 5,595,733, which names Gleta Carswell,
Christian Harms, Yin-Fu Chang and Mary-Dell Chilton as inventors. Novartis had
charged that its patent covered all insect-resistant corn produced with Bt
technology. This sweeping assertion is understandable in light of the broad
language of the first and sole independent claim: "a method of controlling
insect larvae comprising: (a) feeding the larvae an insecticidal amount of
transgenic Zea mays cells containing an isolated or synthetic DNA which
a polypeptide having the insect toxicity properties of a Bacillus
crystal protein, wherein the cells have been grown or cultured in a manner to
permit expression of the toxin in the cells."
A contract dispute concerning Bt toxin technology was also the subject of a
trial last year. In March, a San Diego Superior Court jury awarded $174.9
million in damages to Mycogen in a breach of contract suit against Monsanto.
This case began in 1989 when Monsanto granted options to license technology,
including Bt insect-resistance technology, to Lubrizol Genetics, which was
subsequently acquired by Mycogen. When Mycogen tried to exercise the
options in
1993, Monsanto refused and Mycogen sued. A year later, a San Diego Superior
Court judge granted Monsantoís motion for summary judgment, which effectively
upheld Monsantoís refusal. Mycogen obtained a reversal of the ruling on
and filed the damage suit that led to the $174.9 million award for lost
due to the lack of access to Monsantoís technology. Monsanto filed motions for
a new trial or a modification of the jury verdict, but the Superior Court
denied the motions last May. Placing a positive spin on thi! 
s case, Monsanto noted that earlier the judge had denied Mycogenís contention
that Monsanto must license to Mycogen genetically engineered germplasm
containing Bt genes.
Battle Royal at PTO 
Both the February and June trials raised the issue of the identity of the
party to express a Bt toxin gene in plants or to modify a Bt toxin gene for
increased expression in plants. During the past year, Monsanto representatives
have alluded to an ongoing interference procedure at the U.S. Patent and
Trademark Office (PTO) that would determine the first inventor of the
"basic Bt
An interference proceeding is required when two or more patent applications,
filed by different inventors, claim substantially the same patentable
invention. Since the patent rights of one party would interfere with the
rights of another party, the PTO must determine who is the first inventor of a
patentable invention and entitled to the patent. An interference may involve
either two or more applications or one or more applications, and one or more
patents. In an interference, the patentable invention is defined by a "count,"
which is similar to a patent claim. Each interference party must submit
evidence proving when the invention, described by the count, was made.
Although the details of an ongoing interference are not open to the public, an
issue arose in a Bt toxin interference, which was appealed to the Court of
Appeals for the Federal Circuit. The published decision on this one issue
some light on the nature of the Bt toxin interference (1). In a nutshell,
interference No. 103,781 began in November 1996 when the PTO declared a
three-party interference between the following two patent applications and
issued patent: 1) U.S. Serial No. 07/827,906, entitled "Improved Expression of
Genes in Plants," filed by Kenneth A. Barton and Michael Miller, and assigned
to Agracetus; 2) U.S. Serial No. 08/434,105, entitled "Synthetic Plant Genes
and Method for Preparation," filed by David A. Fischhoff and Frederick J.
Perlak, and assigned to Monsanto; and 3) U.S. Patent No. 5,380,831, entitled
"Synthetic Insecticidal Crystal Protein Gene," filed by Michael J. Adang,
Thomas A. Rocheleau, Donald J. Merlo, and Elizabeth E. Murray and assigned
The PTO devised a single count in the interference, which relates to a method
for enhancing the expression of modified Bt toxin genes in plant host cells.
That count read "A method of designing a synthetic Bacillus thuringiensis gene
to be more highly expressed in plants, comprising the steps of: a) analyzing
the coding sequence of a gene derived from a Bacillus thuringiensis which
encodes an insecticidal protein toxin, and modifying a portion of said coding
sequence to yield a modified sequence which contains a greater number of
preferred by the intended plant host than did said coding sequence, or b)
analyzing the coding sequence of a gene derived from a Bacillus thuringiensis
which encodes an insecticidal protein toxin, and modifying a portion of said
coding sequence to yield a modified sequence which contains a greater
number of
codons preferred by the intended plant host than did said coding sequence and
fewer plant polyadenylation signals than said coding sequence! 
Possible Heir to the Throne 
Shortly after the declaration of the interference, Monsanto bought the plant
biotechnology assets and related intellectual property of Agracetus. Monsanto
wanted to continue the interference with both patent applications because it
was not possible, at least at that time, for Monsanto to choose the best
application for establishing priority of inventorship. This was because
discovery had not yet been completed, and it was not clear what the final
language of the count would be, or what evidence Mycogen would marshal to
establish the date of invention. That is, Monsanto's dilemma was that the
count might be supported by one of its applications and not the other. Not
surprisingly, Mycogen argued that Monsanto had sufficient information to pick
one of the two commonly owned applications. The PTO agreed with Mycogen, but
the Federal Circuit reversed the decision, explaining that the "three party"
interference should continue until the PTO determines the final count and
very is complete. The victor of this interference contest should have a
dominating patent in its arsenal.
Even before the dust of the Bt patent wars has settled, a new contender has
entered the fray. Researchers at the University of Wisconsin-Madison have
announced the discovery of insecticidal toxins produced by Photorhabdus
luminescens (2). Although a U.S. patent has not been issued on these new
bioinsecticides, the UW group does have several international patent
publications. An international patent publication from Bio Integrated
Technology S.R.I (Italy) also concerns P. luminescens toxins and their use as
insecticides. Is this the beginning of insect toxin wars: the next generation?
1. Barton v. Adang, 49 USPQ2d 1128 (Fed. Cir. 1998). A copy of this decision
(No. 97-1491) is also available from the Federal Circuit web site
2. See Bowen D et al. 1998. Insecticidal toxins from the bacterium
luminescens. Science 280:2129-2132; and Bowen DJ and Ensign JC. 1998.
Purification and characterization of a high-molecular-weight insecticidal
protein complex produced by the entomopathogenic bacterium Photorhabdus
luminescens. Applied and Environmental Microbiology 64:3029-3035.
Phillip B. C. Jones, Ph.D., J.D. 
Seattle, Washington