Promega Corp. v. Novagen, Inc. (6 F. Supp. 2d 1004, 1997)

OPINION AND ORDER

CRABB, District Judge.

This is a civil action for injunctive and monetary relief in which plaintiff Promega Corporation alleges that defendant Novagen, Inc. infringed its patents for biotechnological inventions relating to protein synthesis. The parties have filed cross-motions for summary judgment on the validity, enforceability and infringement of the two patents held by plaintiff, United States Patents Nos. 5,324,-637 (’637) and 5,492,817 (’817). The action arises under the patent laws of the United States. 35 U.S.C. §§ 1-371. Jurisdiction is present. 28 U.S.C. §§ 1331 and 1338(a).

In its motion for summary judgment, defendant contends that plaintiffs patents are invalid because: plaintiff engaged in inequitable conduct by affirmatively misrepresenting experimental facts to the United States Patent and Trademark Office; plaintiffs claim's are anticipated by the prior art; and plaintiffs claims are obvious to those skilled in the art. Alternatively, defendant asserts that if plaintiffs patents are not covered by the prior art, defendant’s products do not infringe plaintiffs patents. Plaintiff contests all these arguments vigorously in a series of its own motions for summary judgment. For the reasons articulated below, I conclude that: 1) the term “coupled transcription and translation” as used in plaintiffs patent claims covers reactions in which “any” simultaneous transcription and translation occurs; 2) plaintiff did not intend to limit the scope of its patent claims to the exact sequential order set forth therein; 3) defendant’s STP2 and Amersham system products infringe plaintiffs patents; 4) plaintiff did not engage in inequitable conduct by submitting the First Declaration of Dr. Gregory Beckler to the patent office or by failing to submit the Perara and Lingappa reference; 5) there is a material dispute of fact precluding summary judgment with respect to whether plaintiff engaged in inequitable conduct by submitting the Second Declaration of Dr. Gregory Beck-ler to the patent office; 6) the Lewis et al. reference does not anticipate plaintiffs patent claims; 7) there is material dispute of fact precluding summary judgment with respect to whether the Stueber et al., Coen et al. and Perara and Lingappa references anticipate plaintiffs patent claims; 8) there is a material dispute of fact with respect to whether the Baranov et al. patent application by itself or in combination with the Suzuki reference renders plaintiffs patent claims obvious; and 9) the Baranov et al. patent application cannot be combined with the Lewis et al. reference to render plaintiffs patent claims obvious. A trial will be necessary to resolve the outstanding issues of anticipation, obviousness and inequitable conduct. Anticipation and obviousness will be tried to a jury; the court will try the issue of inequitable conduct.

To succeed on a motion for summary judgment, the moving party must show that there is no genuine issue of material fact and that the moving party is entitled to judgment as a matter of law. Fed.R.Civ.P. 56(c); Celotex Corp- v. Catrett, 477 U.S. 317, 322, 106 S.Ct. 2548, 91 L.Ed.2d 265 (1986); Indiana Grocery, Inc. v. Super Valu Stores, Inc., 864 F.2d 1409, 1412 (7th Cir.1989). The non-movant must do more than present some evidence on an issue it asserts is disputed. Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 249-50, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986) (“[TJhere is no issue for trial unless there is sufficient evidence favoring the non-moving party for a jury to return a verdict for that party. If the evidence is merely colorable, or is not significantly probative, summary judgment may be granted.”). A primary purpose of the summary judgment rule is to “isolate and dispose of factually unsupported claims or defenses,” Celotex, 477 U.S. at 323-24, 106 S.Ct. 2548, a purpose as salutary in patent eases as in any other area of litigation. Chore-Time Equipment, Inc. v. Cumberland Corp., 713 F.2d 774, 778-79 (Fed.Cir,1983); see also Conroy v. Reebok Int’l Ltd., 14 F.3d 1570, 1575 (Fed.Cir.1994).

UNDISPUTED FACTS

A. Parties

Plaintiff Promega Corporation and defendant Novagen, Inc. are Wisconsin corporations with their principal places of business in Madison, Wisconsin. Plaintiff is in the business of manufacturing and selling products to biological researchers. Defendant is in the business of manufacturing and selling products for use in gene expression.

B. Background

In all known living organisms, genetic information is carried in one or more long molecules of a chemical named DNA. These long molecules of DNA are known as chromosomes. Each chromosome comprises a number of subunits called genes. Each gene contains information that can be used to synthesize a single, specific protein. Genes help to synthesize new proteins by a process known as expression, which is composed of two parts, transcription and translation.

Proteins are the fundamental “action” molecules of living cells. Proteins are used both for structural purposes within cells and as enzymes that make the other chemical constituents of cells. The basic organization of all proteins is the same. Proteins are large polymeric molecules consisting of chains of smaller building blocks, called amino acids, that are linked together covalently. The chemical bonds linking amino acids together are called peptide bonds. A polypeptide is two or more amino acids linked by a peptide bond. The identity of a protein and its chemical characteristics are determined by the exact sequence in which amino acids are linked in a polypeptide chain. Although there are only 20 amino adds, they are strung together in different orders to produce the hundreds of thousands of proteins found in nature. Although both polypeptides and proteins are composed of amino acid chains, proteins can be distinguished because they contain the complete sequence of amino acids making up that protein and have sometimes undergone post-translational modifications.

Transcription and translation is the essential method for protein synthesis in all cellular life forms. Transcription begins when messenger RNA polymerase (mRNA) binds to a DNA segment known as a promoter and makes a copy of that information. Translation is the transformation of that mRNA transcript into a protein. Messenger RNA is translated into proteins by large structures called ribosomes that bind to the mRNA. The ribosomes and associated molecules read the information in the mRNA, shifting along the strand of mRNA and adding the specified amino acids to a growing polypeptide.

Living organisms can be divided broadly into two large groups, prokaryotes and euka-ryotes. Prokaryotes are unicellular organisms that lack a nucleus, such as bacteria. Eukaryotes have a nucleus and include higher life forms such as plants and animals. The nucleus of a eukaryotic cell contains a membrane separating the DNA in the nucleus from the rest of the cellular components.

A major difference' between prokaryotes and eukaryotes is the method by which they process DNA into proteins. In prokaryotic cells, the ribosomes and associated molecules that make proteins from mRNA can come into contact with the DNA! This permits translation and transcription to be “coupled,” in the sense that as an mRNA strand is being transcribed from DNA, the protein assembly machinery can begin to work simultaneously on the same mRNA strand, translating the mRNA into protein. In eukaryotic cells, the DNA is confined within the nucleus, while the protein assembly machinery of the cell is located outside the nucleus, in the cell’s cytoplasm. In eukaryotic cells, the mRNA is transcribed in the nucleus and then is transported by cellular mechanisms into the cytoplasm outside the nucleus for translation. Thus, in eukaryotic organisms, the transcription and translation processes take place at physically separate regions within the cell.

With the advent of modern biotechnology, scientists became interested in reproducing proteins not only inside living organisms but in test tubes also, referred to as “in vitro” experimentation. Various researchers performed transcription and translation in vitro reactions and developed the tools and techniques for such reactions.

Numerous patents and patent applications in the field of biotechnology involve specific proteins or methods for making and using proteins. Many valuable proteins occur in nature only in minute quantities, or are difficult to purify from natural sources. Therefore, a goal of many biotechnology inventions is to devise methods to synthesize useful quantities of specific proteins by controlling the mechanism by which living cells make proteins.

C. United States Patent 5,32b,687

On June 28,1994, the United States Patent and Trademark Office granted plaintiff United States Patent 5,324,637. The ’637 patent includes 76 claims that measure and define the protection afforded by the patent. Claims I through 67 are method claims defining specific methods for coupling transcription and translation. Claims 68 through 76 are product claims defining specific products used in methods for coupling transcription and translation. The relevant claims of the ’637 patent read as follows:

1. A method for coupling transcription and translation in a cell-free extract derived from cells from the group consisting of plant and animal cells in a static reaction to produce protein, said method comprising

adding a DNA template to said extract, adding ribonucleotide triphosphates to said extract,

adding a RNA polymerase to said extract, and

adding a sufficient amount of a magnesium salt to said extract to raise the magnesium concentration to a level where RNA is transcribed from said template DNA and the RNA translates into said protein.

2. The method of claim I wherein said extract is rabbit reticulocyte lysate.

3. The method of claim 2 wherein said final magnesium concentration is about 2.5 mM [millimolar] to about 3.5 mM.

4. The method of claim 2 wherein said final magnesium concentration is about 2.6 mM to about 3.0 mM.

5. The method of claim 2 wherein a pol-yamine is added to said lysate.

6. The method of claim 5 wherein said polyamine is added to spermidine.

7. The method of claim 6 wherein said spermidine is added to said' lysate to'a concentration of about 0.2 mM to about 0.4 mM.

8. The method of claim 2 wherein the potassium concentration of said lysate is adjusted to about 40 mM to about 100 mM.

11. The method of claim 2 wherein said polymerase is selected from the group consisting of SP6, T7 and T3 RNA polymerases.

16. The method of claim 2 wherein said DNA template is in a form which is selected from the group consisting of a super-coiled molecule, a covalently closed circular molecule, a linear molecule or a DNA segment made by the process known as a polymerase chain reaction.

17. The method of claim 2 wherein 0.4 mM of each of said ribonucleotide triphosphates are added to said lysate.

34. A method for producing protein from a DNA template having a specific polymerase promoter sequence through coupled transcription and translation in a batch reaction, said method comprising the steps of preparing a solution of eukaryotic cell-free extract of cells selected from the group consisting of plant and animal cells, modifying said extract solution with sufficient concentrations of said template DNA having a specific polymerase promoter sequence, ribonucleotide triphosphates, amino acids and a polymerase corresponding to said promoter sequence of said template DNA, and adding a sufficient amount of a magnesium salt to said extract solution to raise the final magnesium concentration to a level where RNA is transcribed from said DNA template and said RNA translates into protein.

36. The method of claim 34 wherein said extract is rabbit reticulocyte lysate.

37. The method of claim 36 wherein said final magnesium concentration is about 2.5 mM to about 3.5 mM.

38. The method of claim 36 wherein said final magnesium concentration is about 2.6 mM to about 3.0 mM.

39. The method of claim 36 wherein a polyamine is added to said solution.

40. The method of claim 39 wherein said polyamine is spermidine.

42. The method of claim 36 wherein the potassium concentration of said solution is adjusted to about 40 mM to about 100 mM.

45. The method of claim 36 wherein an RNA polymerase is added to the lysate.

46. The method of claim 45 wherein said polymerase is selected from the group consisting of SP6, T7 and T3 RNA polymerases.

47. The method of claim 36 wherein said DNA template is in a form which is selected from the group consisting of a super-coiled molecule, a covalently closed circular molecule, a linear molecule or a DNA segment made by the process known as a polymerase chain reaction.

48. The method of claim 36 wherein said DNA template has a multiple cloning region.

68. A kit for producing protein from a DNA template through coupled transcription and translation, said kit comprising the following components adapted to be used in a batch reaction: eukaryotic cell-free extract of cells selected from the group consisting of plant and animal cells, ribonucleotide triphosphates, RNA polymerase, and magnesium salt at a concentration whereby RNA is transcribed from DNA and RNA translates into protein. 70. A kit as set forth in claim 69 wherein said magnesium salt has a concentration of about 2.5 mM to about 3.5 mM.

76. A eukaryotic cell-free extract for producing protein from a DNA template through coupled transcription and translation in a batch reaction, said extract comprising: cells selected from the group consisting of plant and animal cells, ribo-nucleotide triphosphates, RNA polymerase, and a sufficient amount of a magnesium salt to raise the final magnesium concentration to a level where RNA is transcribed from the DNA template and RNA translates into protein.

The specification of the ’637 patent states: Col. 1, lines 21-25: In prokaryotic cells (bacteria) transcription and translation are “coupled”, meaning that RNA is translated into protein during the time that it is being transcribed from the DNA.

Col 2, lines 4-7: Prokaryotic E. coli cell-free systems are considered “coupled” because transcription and translation occur simultaneously after the addition of DNA to the extract.

The specification of the ’637 patent teaches that the critical component in successful coupling of transcription and translation in eu-karyotic systems is ' the concentration of magnesium ions in the reaction mixture. Magnesium occurs naturally in most rabbit reticulocyte lysates, typically in the range of 4.2 to 5.0 mM. . Production of protein does not occur when magnesium concentrations present in the standard lysate are left unchanged. The inventive concept claimed in the ’637 patent is that the control of the magnesium concentration makes the difference between the success and failure of the coupled transcription and translation reaction.

Plaintiffs expert witnesses have testified that the term “coupled transcription and translation” as used in the key, independent claims of plaintiffs patent refers to:

a reaction in which RNA is translated, into protein during the same time period in which it is being transcribed from a DNA template in one reaction vessel.

Defendant’s expert witnesses have testified to much the same definition. Dr. David H.L. Bishop stated that:

Coupled' has been applied to situations where both transcription and Translation occur in the same reaction tube and at the same time and under specified conditions. Dr. Carl W. Anderson remarked that: Coupled suggests that events are spatially and (most likely) temporally linked so that they do or appear to occur simultaneously in the same reaction vessel.

Dr. Robert Mierendorf explained that:

The term “coupled”' transcription/translation refers to a reaction in which RNA is produced from a DNA template and translated into protein in the same vessel over a single incubation period.

D. United States Patent 5,4.92,817

On February 2Ó, 1996, the United States Patent and Trademark Office granted plaintiff United States Patent 5,492,817. The ’817 patent, includes 17 claims that measure and define the protection afforded by the patent. Claims 1 through 12 are method claims. Claims 13 through 17 are product claims. The relevant claims state:

1. A method for coupling transcription and translation in a eukaryotic cell-free extract to produce protein in a static reaction comprising .the steps of:

adding a DNA template to the extract;

adding ribonucleotides triphosphates to the extract;

adding a RNA polymerase to the extract; and

adding a sufficient amount of magnesium salt to the extract to raise the magnesium concentration to a level where RNA is transcribed from the DNA template and RNA translates into protein.

3. The method of claim 1 wherein the RNA polymerase is selected from the group consisting of SP6, T7 and T3 RNA polymerases.

13. A kit for producing protein from a DNA template through coupled transcription and translation, said kit comprising the following components adapted to be used in a batch reaction: eukaryotic cell-free extract, ribonucleotide triphosphates, RNA polymerase, and magnesium at a concentration whereby RNA is transcribed from the DNA template and RNA translates into protein.

The specification of the ’637 and ’817 patents are identical and the claims are similar. Plaintiff filed the application for the ’817 patent to extend its claims in the ’637 patent to all eukaryotic cell-free extracts, rather than just the plant and animal cell-free extracts of the ’637 patent. The principal difference between the claims of the two patents is that the claims of the ’817 patent would cover cell-free extracts from euka-ryotes that are not plants or animals, such as yeast.

E. Prior Art

Before plaintiff applied for a patent on its protein synthesis product, separate transcription and translation systems were known in the prior art. In separate transcription and translation reactions, DNA is transcribed into RNA in a transcription reaction and the RNA from the transcription mixture is then added to a second reaction, a translation reaction. This type of process would not be considered “coupled” as that term is used in this ease, but would be considered a “linked” or “two-step” process. Plaintiff marketed two-step transcription and translation kits for some time before filing the patent application that became the ’637 patent.

The “References Cited” section of plaintiffs ’637 patent lists one foreign patent document, Russian PCT patent application, WO91/02076 (European Patent No. 0593757A1) (Baranov et al. patent application), as well as a number of “other publications” that include: Zubay, G. (1973) Ann.Rev.Genet., vol. 7, p. 267; Pelham, H.R.B. and Jackson, R.J. (1976) Eur. J. Biochem., vol. 67, p. 247; Walter, P. and Blobel, G. (1983) Meth. Enzymol, 96, 84; Glass, C.A. and Pollard, K.M. (1990) Promega Notes 26; Roberts, B.E. and Paterson, B.M. (1973) Proc.Natl.Acad.Sci. USA, vol. 70, p. 2330; Anderson, C., et al. (1983) Meth. Enzymol, 101,635; Krieg, P. and Melton, D. (1984) Nucl. Acids Res., vol. 12, p. 7057; Roberts, B.E., et al. (1975) Proc.Natl.Acad.Sci. USA, vol. 72, p.1922-1926; Pelham, H.R.B., et al. (1978), Eur. J. Biochem, vol. 82, pp. 199-209; Spirin, et al. (1988) Science, vol. 242, pp. 1162-1164; Ryabova, et al. (1989) Nucl. Acid.Res., vol. 17, No. 11, 4412; Baranov, et al. (1989) Gene, vol. 84, pp. 463-466; Suzuki, J. Biochem., vol. 82, pp. 251-260 (1977). The “Background of the Invention” section of the ’637 patent describes some but not all of the work done by others on in vitro transcription and translation reactions, explaining that in vitro systems were available in the prior art.

I. The Lewis et al. reference

J.B. Lewis, C.W. Anderson, J.F. Atkins and R.F. Gesteland published a paper in 1974 entitled The Origin and Destiny of Adenovirus Proteins, Cold Spring Harbor Symp. Quant. Biol. 39, 581-90 (1974). Plaintiff did not include.this reference in its application for the ’637 patent. The Lewis et al. paper describes a study of the proteins produced by a particular class of virus known as adenovi-ruses. In studying the proteins produced by adenoviruses, the researchers sought to use DNA from the virus to make proteins, without reproducing the virus itself. The paper includes a section entitled “Coupled Protein Synthesis From SV40 DNA,” discussing a linked transcription and translation reaction in a fractionated mammalian cell-free system. Lewis et al. used a DNA template composed of DNA from the SV40 virus and a cell-free extract of mammalian cells made from purified fractions different from the cell-free extracts disclosed in the ’637 and ’817 patents. Ribonucleotide triphosphates (abbreviated “ATP,” “GTP,” “CTP” and “UTP”), 60 (mi-ero)g/ml of RNA polymerase and 5.6 mM of magnesium acetate were added to the reaction mixture. The paper reports that with the addition of the template SV40 DNA, a number of “polypeptides” were synthesized and that “incorporation of amino acid into polypeptide was significantly stimulated by SV40 DNA....” The paper does not report that “proteins” were produced. The experiments performed in this section of the paper were not intended to optimize a coupled transcription and translation system, but rather were designed to study the proteins produced by adenoviruses.

2. The Roberts et al. reference

The 1975 Roberts et al. reference teaches those skilled in the art to synthesize proteins or polypeptides coded by SV40 DNA by performing two sequential reactions, i.e., linked transcription and translation reactions. The first step is a transcription reaction lasting 15 minutes under reaction conditions optimize for transcription. The second step is a translation reaction performed by changing the reaction conditions to optimize them for translation, including changing the temperature and magnesium salt concentration and adding a wheat germ extract. The transcription and translation reactions are separated temporally. There is no suggestion in the reference for changing the time or reaction conditions of either the transcription or translation reaction. Nor is there any suggestion what reaction conditions would be used if one wished to combine the two reactions.

3. The Pelham and Jackson reference

The 1976 Pelham and Jackson reference defined the preparation of rabbit reticulocyte lysate. Today, rabbit reticulocyte lysate is the most popular form of cell-free extract from eukaryotic cells used for in vitro protein translation.

4. The Roberts and Paterson reference

The most practical alternative to rabbit reticulocyte lysate is a wheat germ extract, described in the 1973 Roberts and Paterson reference.

5. The Krieg and Melton reference

The 1984 Krieg and Melton reference describes a linked transcription and translation system. A transcription reaction is performed first under conditions optimal for transcription. Then, mRNA is purified from the products of that transcription reaction. Next, the purified mRNA is added to the translation reaction, with conditions optimized for translation. In Krieg and Melton, there is no opportunity for transcription to occur during translation.

6. The Coen et al. reference

Coen et al., Proc.Natl.Acad.Sci. USA, vol. 74, 5487-5491 (1977) teaches those skilled in the art to synthesize proteins coded by DNA fragments by performing linked transcription and translation reactions. The Coen et al. reference is not cited in either the ’637 or ’817 patents. The first step in the Coen procedure is a transcription reaction for 30 minutes under conditions optimized for transcription, after which conditions are changed to optimize them for translation, including changing the temperature and magnesium salt concentration, and the translation reaction is performed. There is no suggestion in the reference concerning what conditions to use if the two reactions were combined. The reference does not present any data demonstrating that transcription occurs after the initial 15-minute step. The reference teaches that the purification step in Krieg. and Melton is unnecessary.

Defendant conducted seven experiments related to the Coen reference. None of the experiments replicated the exact conditions reported in the Coen piece. Defendant used different components. The first experiment consisted of several reactions using various DNA templates. The second experiment consisted of several reactions during which RNA synthesis was monitored at various times. The experiment showed that if the label 3H-CTP is added at the beginning of the transcription reaction, there appears to be a slight amount of degradation of RNA during the translation reaction and incorporation takes place. The third experiment involved several reactions using different DNA templates at different concentrations. Defendant performed two sequential reactions of the type described by Coen as well as modified reactions in which the two Coen reactions were combined. Protein synthesis was measured by incorporation data and gel analysis. Only two of the five templates produced any specific protein. The fourth experiment consisted of several reactions using dual DNA templates. Defendant performed two sequential reactions of the type described by Coen and also performed modified reactions in which the two Coen reactions were combined. Protein synthesis was determined by gel analysis. The fifth experiment was the same as the third except that this time defendant used 5 (micro)g plasmid and measured incorporated counts as well as a gel analysis.

7. The Stueber et al. reference

D. Stueber, et al., Embo J., 3:3143-3148 (1984) is a 1984 piece that teaches those skilled in the art to utilize a protein expression system by performing linked transcription and translation reactions. The Stueber reference is not cited in either the ’637 or ’817 patents. The first step is a transcription reaction for 20 minutes at conditions optimized for transcription. Then the conditions are altered by changing the temperature and magnesium salt concentration and the translation reaction is performed. The paper does not provide any suggestions on how. to change the reaction conditions in order to perform the reactions at the same time. The paper does not contain any explicit suggestion that transcription occurs after the initial 20-minute first step. The reference shows that the purification step in Krieg and Melton is unnecessary.

8. The Perara and Lingappa reference

Eve Perara and Vishwanath R. Lingappa, A Former Amino Terminal Signal Sequence Engineered to an Internal Location Directs Translocation of Both Flanking Protein Domains, J. Cell. Biol., 101, 2292-2301 (1985) discloses a linked transcription and translation system involving two separate reactions. The Perara and Lingappa reference describes the author’s’ recreation of the Krieg and Melton experiments. The two references differ in that Perara and Lingappa leave out the final purification step before performing the second and separate translation step. Plaintiff never submitted the Per-ara and Lingappa reference to the patent examiner. There is no recognition in the article that either of the reactions is coupled.

Defendant conducted four experiments related to this reference. (None of the experiments replicated the exact conditions reported in the Perara and Lingappa piece. Defendant used different components and different concentrations of a number of components.) The first experiment consisted of several reactions in which defendant varied the magnesium concentration of the translation reaction. The second experiment consisted of several reactions in which defendant varied the time allowed for the transcription reaction. In the third and fourth experiments, defendant compared the experiments of Perara and Lingappa to standard and modified STP2 (defendant’s gene expression product) reactions.

The Perara and Lingappa reference did not come to plaintiffs attention until defendant’s counsel pointed it out to plaintiff in a letter dated March 6, 1995. At that time, the ’637 patent had issued but the ’817 patent was still being prosecuted in the Patent & Trademark Office. Dr. Gregory Beckler, one of plaintiffs scientists, reviewed the Perara and Lingappa reference, concluding that it presented no new information relevant to the claims of plaintiffs proposed patent and that it was cumulative and less material than Krieg & Melton. Plaintiff informed defendant of this conclusion a letter dated April 25, 1995. Plaintiffs kit claims in the ’817 patent each require a polymerase, template and extract, just as Perara and Lingappa’s experiment does.

9.The Baranov et al. patent application

Another piece of prior art is a published Russian PCT patent application, W091/02076 (European Patent No. 0593757A1), referred to here as the Baranov et al. patent application. The Baranov et al. patent application describes a coupled transcription and translation system that is intended to operate in a continuous flow mode. In a continuous flow mode reaction, the protein assembly machinery, or cell-free extract, is placed inside a porous membrane with DNA and other constituents necessary for transcription and translation. Then a buffer is permitted to flow through the membrane to wash out the protein produced and to introduce into the reaction additional raw materials for manufacture of additional protein. In this type of system, some components of the system are continuously added and some are continuously removed as protein is translated over extended periods of time. In contrast, a batch reaction (the type of reaction in the ’637 and ’817 patents) is carried out under one set of conditions in a contained volume. Batch reactions can be run in a small reaction volume, usually twenty-five to fifty microli-ters, and are often completed in one to two hours.

In the Baranov et al. patent application continuous flow system, the lysate components necessary for sustained protein synthesis are retained by a semipermeable membrane of an ultraflltration unit. Example 4 of the Baranov et al. patent application includes two sets of materials, an “incubation mixture” and “buffer A.” The incubation mixture is combined in an ultraflltration unit with buffer A, which contains ingredients necessary for the coupled reaction. Buffer A is pumped continuously through the ultrafil-tration unit, into the incubation mixture and out through the semipermeable membrane. The continuous flow of Buffer A lasts 34 hours. Protein synthesis does not begin immediately but continues throughout the 34 hours once it has started. The membrane is permeable to CAT specific protein, which has a molecular weight of about 30,000 Daltons. Magnesium ions have a molecular weight of 58 Daltons. Thus, the membrane is permeable to magnesium also. The dialysis of buffer A through the Baranov continuous flow system proceeds at rate of 1.5 — 2.0 mis an hour. The initial volume of reaction mixture in the reaction chamber is 0.5. ml.

The second ingredient in buffer A is magnesium acetate (MgAc2), which Baranov et al. report is included in buffer A at a concentration of 1.5 mM. The concentration of magnesium for the initial reaction conditions of Baranov et al. is determined by the concentration of magnesium contained in the rabbit reticulocyte lysate of the incubation mixture plus the magnesium contained in buffer A. The concentration of magnesium in any given rabbit reticulocyte lysate may vary; standard rabbit reticulocyte lysate has a magnesium concentration of 4.2 to 5.0 mM. Baranov et al. does not provide the concentration of magnesium in the rabbit reticulocyte lysate used. Dr. Lyuba Ryabova, a co-inventor on the Baranov et al. patent application who performed the experiment described in example 4, has verified that 1.5 mM of magnesium was added to Buffer A in example 4. Ryabova arrived at the conclusion that 1.5 mM was the proper amount of magnesium to add to Buffer A by performing a series of batch reactions using varying amounts of magnesium. The Baranov et al. patent application does not discuss or suggest how one would convert its continuous flow system to a batch reaction and it does not disclose either the magnesium concentration of its initial reaction conditions or the concentration of magnesium that should be used for a batch reaction.

10. The Baranov et al. Gene reference

Baranov et al. (1989) Gene, vol. 84, pp. 463-466 describes experiments involving naturally coupled, prokaryotic cell extract and E. coli RNA polymerase.

11. The Suzuki reference

The Suzuki, J. Bioehem., vol. 82, pp. 251-260 (1977) reference teaches that the magnesium concentration of rabbit reticulocyte ly-sates used for translation should be optimized for optimum translational efficiency and fidelity. The reference teaches also that the magnesium concentration should be optimized for each individual lysate since results can vary from one lysate to another.

F. Plaintiffs and Defendant’s Products

While plaintiffs application for the ’637 patent was pending, plaintiff was selling the commercial embodiment of the application as its “TNT” kit. Defendant subsequently offered its own one-step coupled transcription and translation product under the name “STT” (Single Tube Protein). Upon learning that its ’637 patent had been approved, plaintiff wrote to defendant, advised it of the forthcoming issuance, of the patent and asserted that defendant’s STP system was an infringement of the ’637 patent. On the basis of that representation, defendant withdrew its product from the market.

In late 1994, defendant introduced a new product, now referred to as “STP2.” Defendant tried to design STP2 to avoid infringement of the ’637 patent. Defendant has another product similar to the STP2, called the Amersham system, which defendant manufactures and sells to a company named Am-ersham. The protocols for each product are substantially the same. Both state that the product is designed for in vitro synthesis of proteins from DNA templates containing a bacteriophage T7 or SP6 RNA polymerase promoter and can be used to express proteins from supercoiled plasmids, covalently closed plasmids or products of PCR. Both the STP2 and the- Amersham systems use a two-step reaction. First, the user of the kit combines a transcription mix including ribo-nucleotide triphosphates, RNA polymerase and magnesium salt with a DNA template and performs a transcription reaction for 15 minutes. In this step, no simultaneous transcription and translation occurs. Following the completion of the transcription reaction, the user adds a sample of the reaction products from the transcription reaction, in unpu-rified form, to a translation mix (consisting of rabbit reticulocyte lysate, amino acids, and nucleotides). This translation step continues for 60 minutes. The translation reaction is a static or batch reaction. During the translation reaction, there is sometimes simultaneous transcription and translation, but not always. When the ingredients are combined in the second step, the magnesium concentration is 2.74 mM.

By letter dated February 16,1995, plaintiff informed defendant that the STP2 system infringed the ’637 patent just as the STP system had. Defendant responded in a letter dated March 6, 1995, denying plaintiff’s accusations. Plaintiff sent another letter to defendant dated April 25, 1995, reasserting its infringement claims. Defendant responded the same way in a letter dated June 19, 1995. No further communication took place until plaintiff filed this suit in February 1996.

G. Patent Application History

Plaintiff filed its original patent application (S.N.775, 136) on October 11, 1991. On March 10, 1992, the examiner of the United States Patent and Trademark Office rejected nearly all of the claims of plaintiffs original patent application, explaining that the invention as claimed in the patent application was anticipated by Baranov et al. (the patent application) and obvious over the work of Baranov et al., in view of Suzuki. The examiner asserted that the Baranov et al. patent application method would result in protein production even without the continuous flow dialysis described therein. Plaintiff responded that Baranov did not include any information useful for setting up a batch reaction. The examiner rejected plaintiffs application a second time on November 3, 1992, stating:

Applicants [sic] remarks do not clearly indicate that Baranov et al. protocol described in the prior art does not work. A Declaration stating the results of the use of the Baranov et al. patent showing the Examiner that the protocol in the prior art cannot work as suggested in the rejection [i.e., as a batch mode] should be submitted if this is what Applicant means.

On February 3,1993, plaintiff appealed the examiner’s decision to the United States Patent Office Board of Appeals and Interferences. Plaintiff filed a reply brief on April 14, 1993, explaining that “coupling means the simultaneous transcription of RNA from a template DNA and the translation of that RNA into a protein.” In that same reply brief, plaintiff refers interchangeably to the Baranov et al. “reference,” “method” and “patent.” On February 23,1994, in a change of strategy, plaintiff withdrew the appeal and filed a continuation application to bring the patent application back to the examiner. The continuation application was assigned a new serial number (S.N.149, 715). Legally and conceptually, the patent application remained the same but the examiner examined it anew. Plaintiff amended its claims to limit them to batch reactions and supplemented its earlier record and arguments with respect to all the rejections entered by the examiner, including those based in whole or in part upon the Baranov et al. patent application. Plaintiff submitted a series of declarations, including one by Dr. Josephine Grosch explaining that plaintiffs product was a commercial success and two by Dr. Gregory Beckler describing his attempts to convert the continuous flow transcription translation reaction of Baranov et al. to a batch reaction.

Dr. Grosch declares in part:

More than 75. scientific experts in a variety of disciplines and R & D Magazine editors selected the commercialized invention TNT Coupled Reticulocyte Lysate System as one of the 100 most technically significant new products of the year.

The commercialized invention TNT Coupled Reticulocyte Lysate System had total sales of over $600,000 in the product’s first year and over $1,000,000 in its second year.

Beckler’s first declaration (The First Declaration of Dr. Gregory S. Beckler), signed by him on February 22, 1994, contains the following statements:

I am familiar with the Baranov et al. reference (“Baranov”) and its disclosed subject matter in that Promega conducted research for over a year, which included the work of myself and other scientists, in attempting to duplicate the results of Bar-anov in order to develop and commercialize in vitro continuous translation/transeription kits based on prokaryotic and euka-ryotic extracts. The majority of these experiments at Promega were done using the naturally coupled, transcription/translation prokaryotic E. Coli S30 extract ...

Promega then abandoned its efforts on getting the Baranov process to work and switched its research focus to eukaryotic extracts. After approximately five months of research using eukaryotic extracts, the key to coupling transcription and translation in a static reaction, Mg concentration, was discovered. Optimization of the claimed method took approximately another four months.

Prior to the development of the claimed method at Promega, I became convinced that the Baranov method would not work as a continuous transcription/translation system with the information provided as did other researchers in the translation field. During the period from 1991-1992,1 discussed the Baranov method, i.e. continuous-flow cell-free (CFCF) with other researchers in the translation field. Many researchers had tried the Baranov procedure without any success. Researchers I spoke with questioned the validity of the method, which became evident.in a 1992 publication ... On the first page of the [1992] publication, the authors reference the CFCF coupled transcription/translation system of Spirin and his co-workers. This [sic] the same work as in the Baranov reference. Baranov is a co-worker of Spir rin and this technology is most often known in the translation field as the Spirin work because Spirin is the head of the Russian scientists working on CFCF ...

Promega scientists never attempted to run the Baranov system with a eukaryotic extract in a static mode. During the development of the claimed method at Promega and at- the time the parent application to the above-identified patent application was filed, I did not believe the Bara-nov system could be converted to a static system and actually work to produce protein due to Promega and other researchers [sic] problems in getting the system to work in a continuous mode;

Further, it is my opinion that the conditions disclosed in the Baranov reference would not work for eukaryotic extracts under static conditions ...

Part of Beekler’s first declaration refers to RNA polymerase and magnesium concentrations that are the concentrations found in example 4 of the Baranov et al. patent application.

In his second declaration (The Second Declaration of Dr. Gregory S. Beckler), dated March 10,1994, Beckler states in part:

I designed and performed two experiments in an attempt to convert the continuous transcription/translation reaction of the Baranov reference to a batch reaction.

The first experiment (hereafter “Reaction 1”) utilized the incubation mixture alone as defined in Baranov Example 4. The second experiment (hereafter “Reaction 2”) utilized the incubation mixture and buffer A as defined in Baranov Example 4. See Exhibit 1 attached hereto for Table A which shows the components, concentrations, and amount added for a 0.5 ml batch Baranov incubation mixture. See Exhibit 2 attached hereto for Table B which shows the components, concentrations, and amount added for a 0.5 ml batch Baranov buffer A.

The text of the declaration does not mention that exogenous magnesium was not added to buffer A in Reactions 1 and 2, although that information is contained in table B attached to the declaration. (Tables A and B are appended to this opinion). The second line of table B shows that the only magnesium used in the reactions was the 1.53 mM of magnesium inherently present in the rabbit reticu-locyte lysate. Beckler had read the ’637 patent application before submitting his declarations. That application stated, “Leaving magnesium concentrations at levels present in the standard lysate, protein production does not occur.”

In Reaction 1, Beckler utilized the incubation mixture alone as defined in Baranov example 4 but changed some of the concentrations of the ingredients in attempts to make the mixture work in batch mode. For this first experiment, Beckler added the incubation mixture to water instead of buffer A. (The constituents of the incubation mixture as prepared by Baranov et al. and by Beckler are set forth in attached table A. The ingredients of buffer A as prepared by Baranov et al. and by Beckler are set forth in attached table B.) In Reaction 2, Beckler used the incubation mixture and buffer A as defined in Baranov example 4 (again changing the ingredient concentrations to account for the conversion to batch mode), plus water to make 0.5 ml (13.15(micro)l). Beckler did not add any exogenous magnesium acetate to buffer A but relied instead on the magnesium concentration present in the reticulocyte ly-sate. Beckler used a 60 % volume of a special Promega reticulocyte lysate (Flexi®) that has a magnesium concentration of 2.5 mM to achieve a final magnesium concentration of 1.53 mM. Beckler completed a gel autodiagram showing that no protein was produced using the conditions of Baranov.

On March 11, 1994, plaintiffs attorneys Dave Smith and Billy Jean Strandt and plaintiffs employees Greg Beckler and John Schulz met with United States Patent and Trademark Office examiner Robert Wax and supervisory examiner David Schmichel. Plaintiff submitted the Second Declaration of Dr. Gregory Beckler in person at that time. The Examiner’s Interview Summary Record reports that the second Beckler declaration demonstrates that “Baranov et al. as a static reaction does not work.” Relying on that information, the examiner decided that he had erred in rejecting plaintiffs claims and withdrew that rejection. On March 22, 1994, the patent examiner issued a “Statement of Reasons for Allowance” stating:

Applicants have submitted declaration by Beckler that indicates that the Baranov et al. method of in vitro protein synthesis does not work as described. By performing the reaction as directed in the Baranov et al. reference, but in a batch mode, applicants have demonstrated that no protein is produced. Applicants had also presented evidence that the Baranov et al reference could not be used with some experimentation to produce proteins as is described in the reference in the continuous mode. As the reference did not enable those-of ordinary skill in the art to make protein either in batch as claimed nor much protein in a continuous mode as detailed in the prior art the instant invention is not obvious over that reference. Applicants have presented additional data that indicates the invention is a commercial success.

On June 28, 1995, plaintiffs attorneys filed the same Beckler declaration asking the patent examiner to allow its ’817 patent. On September 26, 1995, the patent office issued a “Notice of Allowability,” citing the same reasons for allowing the patent as mentioned with respect to the ’637 patent.

Dr. Robert C. Mierendorf, one of defendant’s scientists, reviewed Dr. Beckler’s reports of his attempt to replicate the experiments of Example 4 of the Baranov et al. patent application and convert it to batch mode. Under Mierendorfs direction, scientists for defendant replicated Beckler’s “Reaction 2” experiment as Mierendorf understood it. These same scientists performed the same experiment with the addition of exogenous magnesium in the amount of 1.5 mM in the Buffer A as specified by Baranov et al. These experiments showed that if Beckler had added exogenous magnesium to the reaction mixture, protein would have been produced. Mierendorf reviewed the additional experiments performed by Robin Hurst at the plaintiff company on the same issue. Plaintiffs data revealed that its experiments yielded the same result as defendant’s experiments, i.e., protein is produced when 1.5 mM of exogenous magnesium is added to Buffer A.

In deposition testimony, Beckler acknowledged that he had never attempted to duplicate the Baranov et al. patent method in a continuous flow mode. Two of plaintiffs scientists, doctors John Van Herwynen and Tom Van Oosbree, attended a talk in June 1990 by Dr. Alexander Spirin (a colleague of Baranov). Van Herwynen and Van Oosbree submitted a two-page written report to Beck-ler that explained, among other things, that “eukaryotic systems can be supplemented with SP6 or T7 RNA polymerases and perform better than prokaryotic systems.”

OPINION

I. INFRINGEMENT

Each party has moved for summary judgment on plaintiffs claim that defendant’s STP2 and Amersham system products infringe plaintiffs ’637 and ’817 patents. As the patent owner, plaintiff has the burden of proving infringement by a preponderance of the evidence. ZMI Corp. v. Cardiac Resuscitator Corp., 844 F.2d 1576, 1582 (Fed. Cir.1988). The determination whether a patent claim has been infringed involves two steps: 1) the scope and meaning of the claim are construed without regard to the accused product; and 2) the claim is compared with the accused product to determine whether all of the limitations of the claim are present either exactly or by substantial equivalents. Carroll Touch, Inc. v. Electro Mechanical Sys., Inc., 15 F.3d 1573, 1576 (Fed.Cir.1993); Lemelson v. General Mills, Inc., 968 F.2d 1202, 1206 (Fed.Cir.1992). The first inquiry is a legal question; the second is factual. Markman v. Westview Instruments, Inc., 517 U.S. 370, 116 S.Ct. 1384, 1393, 134 L.Ed.2d 577 (1996) (citations omitted).

A. Claim Construction

Construction of the claims precedes all subsidiary questions, including validity and infringement. In re Hayes Microcomputer Products, Inc. Patent Litigation, 982 F.2d 1527, 1541 (Fed.Cir.1992). Claim construction allows a court to elaborate on a patentee’s “normally terse language” in the patent claims in order to understand and explain, but not to change, the scope of those claims. Scripps Clinic & Research Found, v. Genentech, Inc., 927 F.2d 1565, 1580 (Fed. Cir.1991). In construing the scope and meaning of patent claims, a court should consider three sources: the claims, the specification and the prosecution history. Markman v. Westview Instruments, Inc., 52 F.3d 967, 979 (Fed.Cir.1995), aff'd, 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996) (citations omitted). The key terms of a claim are to be interpreted according to their ordinary and accustomed meaning to those skilled in the art, unless it appears from the specification that the inventor used them differently. Beachcombers v. WildeWood Creative Prods., Inc., 31 F.3d 1154, 1158 (Fed.Cir.1994); Carroll Touch, 15 F.3d at 1577. Expert testimony may be used to explain how those skilled in the art would interpret the claims. Markman, 52 F.3d at 979 (citation omitted). A patentee may act as his own lexicographer and define key terms in the patent. As long as the patentee clearly spells out the special definition of a term in the specification and uses the term in the same way in the claims, that definition will be controlling for purposes of claim interpretation. Id. at 979.

The parties ask the court to construe two elements of plaintiffs patents. First, the parties seek an interpretation of the term “coupled transcription and translation,” a term used in each of the key, independent claims in plaintiffs ’637 and ’817 patents. (Claim I of both the ’637 and ’817 patents employs the term “coupling transcription and translation.” The distinction between coupled and coupling is immaterial and I will treat the two words as one and the same for purposes of this opinion.) Second, the parties look to the court to decide whether claims 1-6, 8, 11, 16, 34, 36-40, 42 and 45-48 of the ’637 patent and claims 1 and 3 of the ’817 patent cover only the exact sequential order of the process steps set forth therein.

1. Construction of the term “coupled transcription and translation”

Plaintiff contends that “coupled transcription and translation” means that “DNA is transcribed to RNA and that RNA is translated to protein during the same reaction, i.e. simultaneously.” Defendant agrees that “coupled” signifies simultaneous transcription and translation, but suggests that the court must specify whether “coupled transcription and translation” covers reactions in which there is any simultaneous transcription and translation or pertains only to reactions in which all of the transcription and translation occur simultaneously. According to defendant, if the term encompasses reactions in which “any” simultaneous transcription and translation occurs, plaintiffs patents are covered by the prior art two-step reactions; if the term means that “all” simultaneous transcription and translation must take place in the same reaction, defendant’s products do not infringe.

Plaintiffs patents provide little guidance to the precise meaning of the term coupled transcription and translation. The patent claims do not define the term. The specifications of both the ’637 and ’817 patents signify only that coupled transcription and translation refers to reactions that take place “during the [same] time,” or “simultaneously.” The prosecution history renders much the same vague insight: plaintiffs reply brief on its appeal of the patent examiner’s final rejection of its patent application explains that “ ‘coupling’ means the simultaneous transcription of RNA from a template DNA and the translation of that RNA into a protein.” It is apparent that plaintiff intended the term coupled to signify simultaneous transcription and translation. But plaintiff did not spell out clearly in the patent specifications whether coupled transcription and translation should apply to reactions with “any” simultaneous transcription and translation or only to processes in which “all” transcription and translation for the entire experiment take place at the same time. Plaintiffs failure to do so means that it did not act as its own lexicographer on that question and that the term must be accorded its ordinary and accustomed meaning to those skilled in the art.

The definitions of the term “coupled” offered by plaintiffs and defendant’s experts do not resolve the dispute. Instead, they tend to suggest that plaintiffs choice of the word “simultaneous” as a synonym for coupled is accurate. Defendant protests that defining coupled transcription and translation merely as simultaneous transcription and translation does not adequately distinguish the reactions in plaintiffs patents from the linked or two-step reactions available in the prior art. According to defendant, claims should be construed to maintain their validity if possible, see Whittaker Corp. by Technibilt Div. v. UNR Industries, Inc., 911 F.2d 709, 711 (Fed.Cir.1990), and if the court does not construe the term “coupled” to mean that all transcription and translation takes place simultaneously, plaintiffs claims are invalid because they are anticipated by several two-step reaction references, Roberts et. al., Perara and Lingappa, Stueber et al. and Coen et al. I will address defendant’s arguments about the invalidity of plaintiffs patents in another section of this opinion and say here only that those arguments do not lead me to construe plaintiffs claims simply to avoid a defense of anticipation. See Coming Glass Works v. Sumitomo Elec. U.S.A., 868 F.2d 1251, 1256 (Fed.Cir.1989) (court should not redraft claim to avoid defense of anticipation).

There is nothing in plaintiffs patents indicating that plaintiff intended to limit its use of the term “coupled transcription and translation” to reactions in which all transcription and translation takes place together, i.e., reactions that were not preceded by a separate translation step. If any coupling takes place as a result of the processes that plaintiff describes in its patent claims, then plaintiffs patent claims cover that reaction. As defendant points out, this may pose plaintiff some problems in dealing with the defense of anticipation. But anticipation is not a reason to limit the breadth of plaintiffs claims when' the claims themselves appear broad. Thus, to the extent it is necessary to elaborate on the scope of plaintiffs use of the term “coupled transcription and translation,” I find the term covers reactions in which there is any simultaneous transcription and translation.

2. Order of process steps in plaintiffs claims

The parties dispute whether claims 1-6, 8, 11, 16, 34, 36-40, 42 and 45-48 of the ’637 patent and claims 1 and 3 of the ’817 patent cover only the exact sequential order of the process steps set forth therein. Defendant asserts that plaintiffs claims must be read to encompass only reactions that follow the specific order laid out in the patent claims. Plaintiff says that defendant’s position is too narrow a reading of plaintiffs claims.

In support of its position, defendant cites Loral Fairchild Corp. v. Victor Co. of Japan, Ltd., 906 F.Supp. 798 (E.D.N.Y.1995) and Thom EMI N. Am., Inc. v. Intel Corp., 928 F.Supp. 449 (D.Del.1996). According to defendant, Loral and Thom stand for the proposition that process claims should be limited to the chronological sequence of the steps that make up the claims. In Loral, the court explained:

Predominant language norms suggest recounting process steps in a chronological sequence. . A process description ■ flows most naturally from one step in the sequence to the next in chronological order. The process step described third in sequence thus generally precedes the step described fourth.

Id. at 805. The court cited this language with approval in Thorn, 928 F.Supp. at 457. However, neither of the courts adopted a position as broad as defendant suggests. Although in Loral the court relied on “predominant language norms” to a certain extent, it found other evidence in the patent itself that the patentee intended to specify an exact procedural sequence. Loral, 906 F.Supp. at 805. For example, the court determined that because the “edges of [the] implanted barrier regions” could not be “aligned” with the “vertical edges of the insulation layer” (as required by the patent claim at issue) until the insulation layer was in place, the claim was limited to a process in which the insulation layer always preceded the implanted barrier regions. Id. Moreover, language in the specification arid in the prosecution history of the patent supported a chronological sequence interpretation of the claim. Id. (specification discussed “next” step; prosecution history included dependent claim that mentioned “prior” step). The patent claims at issue in Thorn, 928 F.Supp. 449, were even plainer in specifying an exact sequential order. The steps of the claims were separately ordered (step (a), step (b), etc.) and two of the claims stated step (a) “then” step (b). Id. at 457.

There is scant indication in plaintiffs claims themselves that plaintiff intended the patent to cover only the exact sequential addition of ingredients. If plaintiff had sought to limit its claims to a specific sequence, it could have added language such as “then” or “and thereafter” to the steps of the claim. See Bio-Rad Laboratories, Inc. v. Nicolet Instrument Corp., 739 F.2d 604, 614 (Fed.Cir.1984). Without such an indication in the language of the claims themselves, I cannot find that plaintiff intended to limit the scope of its claims in the manner defendant suggests. See Vaupel Textilmaschinen KG v. Meccanica Euro Italia S.P.A., 944 F.2d 870, 880 (Fed.Cir.1991) (exact order of steps “not specifically set forth” in claim).

B. Infringement

There are two forms of patent infringement: literal infringement and infringement under the doctrine of equivalents. In both cases, the patent owner bears the burden of proving infringement by a preponderance of the evidence. ZMI Corp., 844 F.2d at 1582; 35 U.S.C. § 271(a). Only literal infringement is at issue in this case.

Patent infringement requires that every element of the patent, claim be found in the accused device either literally or equivalently. Johnston v. IVAC Corp., 885 F.2d 1574, 1577 (Fed.Cir.1989); ZMI, 844 F.2d at 1582. Literal infringement requires that the accused device embody every element of a claim. Jurgens v. McKasy, 927 F.2d 1552, 1560 (Fed.Cir.1991) (where all claim limitations are present in the accused device exactly, the claims “read on” the accused device and literal infringement is made out); Johnston v. IVAC Corp., 885 F.2d 1574, 1577 (Fed.Cir.1989) (where a device does not “read on” an accused device exactly there can be no literal infringement). In determining infringement, defendant’s product must be compared with the properly construed claims of the patent, not with the patent holder’s commercial product or the preferred embodiments described in the specification of plaintiffs patent. Amstar Corp. v. Envirotech Corp., 730 F.2d 1476, 1481-82 (Fed.Cir. 1984). The mere addition of elements or functions to an otherwise infringing combination does not negate infringement. Id. at 1482. Section 217(b) of Title 35 U.S.C.