In a recent decision, a divided panel of the U.S. Court of Appeals for the Federal Circuit once again applied Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005) (en banc) to vacate a United States International Trade Commission (“ITC”) claim construction, finding that the specification contained a controlling definition of a claim term. The majority reached this conclusion despite the presence of other specification language, including at least one example that fell outside that definition. In Sinorgchem Co. v International Trade Commission and Flexsys America L.P. (2006-1633, December 21, 2007), an appeal from the ITC, the Federal Circuit found that the ITC’s finding of literal infringement was based on an erroneous construction of the term “controlled amount” in the claims at issue, and thus, vacated the ITC’s order. The Federal Circuit further remanded the case to the ITC to determine infringement under the doctrine of equivalents and invalidity of the asserted patents only if infringement was determined.

Case Background

About three years ago, Sinorgchem Co., Shangdong (“Sinorgchem”), a Chinese company that sells the chemical 6PPD (a rubber antidegradant) and its intermediate 4-ADPA for importation to the United States, was brought before the ITC by Flexsys America L.P. (“Flexsys”), which claimed Sinorgchem was unlawfully importing articles that either infringe a valid U.S. patent or are produced by a process covered by the claims of a valid U.S. patent. Flexsys contended that Sinorgchem was infringing claims 30 or 61 of U.S. Patent 5,117,063 (“the ‘063 patent”) and claims 7 or 11 of U.S. Patent No. 5,608,111 (“the ‘111 patent”).1 These patents describe methods for producing 4-ADPA and 6PPD involving a step of “reacting the aniline and nitrobenzene in a confined zone at a suitable temperature, and in the presence of a suitable base and controlled amount of protic material to produce one or more 4-ADPA intermediates” (Claim 61 of the ‘063 patent, Col. 15, ll. 34-46). The Administrative Law Judge (“ALJ”) issued a determination that Sinorgchem had infringed the claims. In re Certain Rubber Antidegradants, No. 337-TA-533 (I.T.C. Feb. 17, 2006) (final initial and recommended determinations).

The central issue in dispute was the construction of the term “controlled amount of protic material.” Sinorgchem sought to have the term construed to mean “up to about 4% water in the reaction mixture when aniline is the solvent.” Sinorgchem at 4. Under this construction, Sinorgchem would not infringe because its process uses more than 4% water. Flexsys, on the other hand, sought to construe the term to mean “that the amount of protic material should be controlled between an upper limit and a lower limit,” where the upper limit was “that amount beyond which the reaction between nitrobenzene and aniline is inhibited,” and the lower limit was “that amount below which the desired selectivity for 4-ADPA intermediates is not maintained.” Id. Under the Flexsys claim construction, the Sinorgchem process would infringe. The ALJ rejected the Sinorgchem claim construction, adopted the Flexsys construction of the term “controlled amount,” and found that the Sinorgchem process for making 4-ADPA and 6PPD literally infringed the asserted claims of the Flexsys asserted patents, which also were found not invalid as indefinite and obvious in view of the prior art. Id.

In its review of the ALJ’s recommended determinations, the ITC rejected both the ALJ’s and Sinorgchem’s proposed constructions of the term “controlled amount” but re-construed the term as specifying that an upper limit is determined when protic material “inhibits the reaction of aniline with nitrobenzene.” 2 Id. at 4-5. Because the ITC’s claim construction rejected the 4% water limit, and based on the minimum acceptable conversion rate disclosed in the specification, the ITC affirmed the ALJ’s determination and found literal infringement of the Flexsys process for making 4-ADPA and 6PPD. Id. at 5. Sinorgchem appealed the ITC’s decision to the Federal Circuit.

The Appeal: Defining a Definition

The Federal Circuit panel (Judge Timothy Dyk; writing for himself and Judge Lee Yeakel; Judge Pauline Newman dissented) relied on Phillips and confirmed that “the specification may reveal a special definition given to a claim term by the patentee that differs from the meaning it would otherwise possess. In such cases, the inventor’s lexicography governs.” Id. at 7, citing Phillips at 1316. The panel concluded such a definition existed in this case, where the specification set off the term “controlled amount” by quotation marks - “often a strong indication that what follows is a definition.” Id. at 7. Moreover, the use of the word “is” after the term may “signify that a patentee is serving as its own lexicographer.” Id. citing Abbott Labs. v. Andrx Pharms., Inc., 473 F.3d 1196, 1210 (Fed. Cir. 2007). Thus, based on the description presented in the specification, the court found that the drafter of the asserted patents “clearly, deliberately, and precisely defined the term ‘controlled amount’ of protic material as ‘an amount up to that which inhibits the reaction of aniline with nitrobenzene, e.g., up to about 4% H2O based on the volume of the reaction mixture when aniline is utilized as the solvent.’” Id. at 8.

The panel disagreed with the ITC’s finding that the “e.g., up to about 4% H2O …” language used in the specification was an example and not part of the definition. Id. at 9. The decision explained that “[w]hen the specification explains and defines a term used in the claims, without ambiguity or incompleteness, there is no need to search further for the meaning of the term.” Id. at 10, citing Multiform Desiccants, Inc. v. Medzam, Ltd., 133 F.3d 1473, 1478 (Fed. Cir. 1998). Here, the Federal Circuit found that “[w]hen aniline is used as the solvent, the express definition is neither ambiguous nor incomplete - the ‘controlled amount’ is ‘up to about 4% H2O based on the volume of the reaction mixture’ - and we need look no further for its meaning.” Id.

With respect to the ITC’s finding that the 4% limit language was inconsistent with a “preferred embodiment” - Example 10 uses more than 10% water in a reaction where aniline is the solvent - the court relied on Telemac Cellular Corp. v. Topp Telecom, Inc., 247 F.3d 1316, 1326 (Fed. Cir. 2001) and N. Am. Container, Inc. v. Plastipak Packaging, 415 F.3d 1335 (Fed. Cir. 2005), and stated that where multiple embodiments are disclosed, the claims should be interpreted to exclude embodiments that are inconsistent with unambiguous language in the patent’s specification or prosecution history. Id. at 11. “The description of those embodiments did not call for a different construction.” Instead, those embodiments “could not provide the structure or equivalent structure for performing the claimed function” and were therefore outside of the scope of the claims. Id. at 12, citing Rheox, Inc. v. Entact, Inc., 276 F.3d 1319, 1327 (Fed. Cir. 2002). Furthermore, the Federal Circuit found that Example 10 does not specifically disclose the amount of water used in the reaction, and is not even directed toward illustrating the control of the amount of protic material to be used in the reaction. Therefore, this embodiment is “entitled to little weight, and cannot override the clear definition language set forth in the specification.” Id. at 12-13.

In summary, the majority concluded that the correct construction of the term “controlled amount” is that defined expressly in the specification to include the “up to about 4% H2O” limitation. Id. at 15. Based on this construction, each asserted claim can only encompass processes that utilize at most 4% water when aniline is the solvent. Id. Because Sinorgchem always uses more than 4% water in its process for making 4-ADPA and 6PPD products, there is no literal infringement of any of the asserted claims. Id.

The Dissent

In the dissenting opinion, Judge Newman disagreed with the panel majority’s construction of the term “controlled amount” to include the numerical limitation, e.g., the 4% water limit, and stated that such construction excludes a major part of the invention described in the specification’s text and specific examples. Judge Newman further emphasized that the entire specification, including the description and examples, must be considered in construing the claims. The judge stated that the panel majority’s claim construction arbitrarily limited the claim scope, contrary to the content of the specification, thus, creating inconsistency and unpredictability regarding patent claiming.

This Federal Circuit decision once again emphasizes the importance of proper drafting and claim construction in patent infringement disputes. To avoid ambiguity in claim construction, a patent drafter must clearly, deliberately, expressly and precisely define terms used in the claims in the specification, especially when the drafter chooses to act as lexicographer. Although the entire specification must be consulted in construing the claims, under this decision a patent drafter who uses words of definition in a specification may not be able to rely on certain embodiments or other language in the specification to expand upon that definition.