The opinion of the court was delivered by: Lewis A. Kaplan, District Judge
Plaintiff charges defendants with infringing its patent claiming an improved process for the synthesis of a chemical compound used in the manufacture of certain pharmaceuticals by selling in the United States the antidepressant drug citalopram, which defendants allegedly made using the compound synthesized according to plaintiff's patented process. Defendants have filed a counterclaim for declaratory judgment against plaintiff.
Magistrate Judge Ronald L. Ellis held a Markman*fn1 hearing to determine the construction of a number of disputed terms in the patent and issued a Report and Recommendation ("R & R") construing the disputed terms. Defendants object.
Plaintiff Infosint, S.A. ("Infosint") owns the patent at issue in this case, U.S. Patent 6,458,973 (the "'973 patent"). It claims an improved process for making the compound 5-carboxyphthalide, which is used as an intermediate product in the synthesis of citalopram. Citalopram is a well-known antidepressant marketed in the United States under the names Celexa and Lexapro.*fn2
The compound 5-carboxyphthalide had been synthesized successfully prior to the inventors' application for the '973 patent. What the inventors claimed was a superior manufacturing process, especially useful in industrial settings.*fn3 Their innovations included reacting the constituent compounds at a lower temperature and in a manner that did not generate a noticeable emission of gases.*fn4 Additionally, the inventors claimed the use of a new reaction medium, fuming sulfuric acid, in place of liquid sulfur trioxide.*fn5
In general terms, the process involves adding terephthalic acid to fuming sulfuric acid containing at least 20 percent sulfur trioxide, SO3. Fuming sulfuric acid, also known as oleum,*fn6 is a mixture of sulfuric acid and sulfur trioxide.*fn7 Next, formaldehyde is added to the mixture, which is heated at 120-145§ C. The resulting 5-carboxyphthalide then is isolated from the solution*fn8.
Defendants, H. Lundbeck A/S, a Danish corporation, Lundbeck, Inc., its U.S. subsidiary (collectively "Lundbeck"), Forest Laboratories, Inc., and Forest Phramaceuticals, Inc., both Delaware corporations, (collectively "Forest"), manufacture, market, and sell citalopram.*fn9 Lundbeck synthesizes 5-carboxyphthalide at seven manufacturing facilities located outside of the United States.*fn10 It manufactures also the antidepressant drugs citalopram and escitalopram in Denmark.*fn11 Plaintiff alleges Lundbeck uses the 5-carboxyphthalide synthesized according to the process described in the '973 patent as an intermediate product in its production of citalopram and escitalopram. Forest markets and sells in the United States citalopram and escitalopram produced by Lundbeck under the trademarks Celexa and Lexapro, respectively.*fn12
Citalopram is a compound with a stereogenic carbon center, or a carbon atom with four substituents bonded to it.*fn13 Molecules with stereogenic centers can exist in two different, mirror image forms known as enantiomers.*fn14
Enantiomers appear identical in two dimensional depictions, but are revealed as mirror images when viewed in three dimensions.*fn15 To avoid confusion, chemists use different notations to differentiate enantiomers in two dimensional drawings.*fn16 A molecule with one stereogenic center, like citalopram, has only two enantiomers.*fn17 These are known as the Senantiomer and R-enantiomer.*fn18 When these two enantiomers appear in a mixture in a one-to-one ratio, the mixture is known as a racemate or racemic mixture.*fn19 The drug Celexa is composed of racemic citalopram. Lexapro is generally considered more effective, and consists of substantially pure S-citalopram or escitalopram only.*fn20
The parties dispute the construction of five terms or phrases contained in the '973 patent. The parties submitted extensive briefing, and a Markman hearing was held on May 1, 2008/ Defendants object to four of the recommended constructions set out in the R&R.
A. Objection to the Legal Standard
Defendants object first that Magistrate Judge Ellis applied an incorrect legal standard in analyzing the construction of the '973 patent claims. Specifically, defendants object to the R & R's statement that "[g]enerally, claims should be given their broadest meaning unless clearly disavowed in the specification of the patent."*fn21 They argue that in Phillips v. AWH Corp.,*fn22 the case cited for this proposition, the Federal Circuit stated that claims are given their "broadest reasonable construction" only during prosecution before the Patent and Trademark Office ("PTO").*fn23
The Phillips court used the "broadest reasonable construction" language in the course of describing the PTO's examination process. But defendants erroneously focus their attention on only this single sentence in Phillips.
The Federal Circuit in Phillips provided extensive guidance on the basic principles of claim construction.*fn24 It instructed that courts are to give the words of a claim "their ordinary and customary meaning," which it defined as the meaning that "the term would have to a person of ordinary skill in the art in question at the time of the invention."*fn25 To determine the customary meaning of claim terms, courts are directed to look to the context of the entire patent, including the other claims, the specification, and the prosecution history.*fn26 Finally, extrinsic evidence may be considered in light of the intrinsic evidence, but courts should give it "less significan[ce] than the intrinsic record."*fn27
Magistrate Judge Ellis fully and accurately summarized these claim construction principles and applied them correctly to the analysis of each of the disputed terms. Accordingly, even if, as defendants argue, the "broadest meaning absent disavowal" formulation applies only before the PTO,*fn28 the use of the phrase did not affect the result -- a result with which this Court independently agrees.