Word choice can make or break a U.S. patent. This is especially true with regard to the specification and the language used during prosecution of a patent. Moreover, language that might be innocuous or even favored in one jurisdiction may spell doom in another.

A key to patent drafting for U.S. patent applications may be balanced; there are no "one size fits all" patents, and patent owners should utilize a balance to establish a basis for the desired claim scope in multiple jurisdictions. One important area to keep in mind while drafting a U.S. patent application is to avoid patent profanity but to position the application, through well-chosen alternatives, to shine in multiple jurisdictions, particularly the U.S. and Europe.

Patent profanity refers to words of characterization, generally absolute characterization.  At the USPTO and the Federal Circuit, these terms have been held to be limiting and can result in unfortunate endings for patent owners alleging infringement. In this two-part series, we will look at several examples of patent profanity, how the Federal Circuit has ruled regarding these terms, and some considerations for drafters, including those drafters involved in patent applications with foreign counterparts, where such characterization language may be typical and even (dare we say) necessary.


In Atofina v. Great Lakes Chemical Corp., 441 F.3d 991 (Fed. Cir. 2006), the limitation at issue was "chromium catalyst":

Claim 1. Process for the manufacture of difluoromethane consisting essentially of gas-phase catalytic fluorination of methylene chloride with anhydrous hydrofluoric acids ..., at a temperature of between 330 and 450 Cº and with a bulk or supported chromium catalyst. (emphasis added)

The appellant argued that the district court incorrectly construed the term "chromium catalyst" as excluding "metal oxides" and "non-inert additives" based on statements in the specification and the prosecution history. According to the appellant, when read in context, the statements relied on by the district court did not amount to a "clear and unmistakable" surrender of subject matter.

The Federal Circuit, however, agreed with the district court, noting that the specification stated that "it is necessary to have a catalyst containing solely chromium." Id. at 997 (emphasis added). Additionally, the Federal Circuit noted that the appellants had argued during prosecution that it was "unnecessary to employ special additives to increase [the catalyst's] selectivity." Id.  This led the Federal Circuit to hold that the district court did not err in its claim construction, and that the appellant's statements disclaimed catalysts containing metal oxides and non-inert additives. Since the respondent's catalyst included a material other than chromium, the Federal Circuit found that the respondent's catalyst was not limited to "solely chromium," and did not infringe appellant's claims.


In an appeal against a judgment of noninfringement, the appellants in Pharmacia & Upjohn Co. v. Mylan Pharmaceuticals, Inc., 170 F.3d 1373 (Fed. Cir. 1999) argued that Mylan Pharmaceuticals' ("Mylan") micronized glyburide compositions infringed the asserted claims under the doctrine of equivalents, allegedly because "anhydrous lactose is the equivalent of spray dried lactose." The independent claim at issue read (emphasis supplied):

Claim 1. In an [sic] micronized anti-diabetic pharmaceutical composition as a unit dose, containing one or more pharmaceutically acceptable excipients, the improvement which comprises: spray-dried lactose as the preponderant excipient in said composition, being present therein at about not less that [sic] seventy percent (70%) by weight of the final composition.

The district court held that prosecution history estoppel barred application of the doctrine of equivalents, noting Pharmacia & Upjohn Co.'s ("Pharmacia") arguments during prosecution that "the use of spray dried lactose was a 'critical' feature of the invention," and emphasizing the "criticality" of using spray dried lactose as the principal excipient in their pharmaceutical composition. Id. at 1375, 1377 (emphasis added).

The Federal Circuit agreed with the district court and held that "these statements would reasonably be interpreted as a 'clear and unmistakable surrender' of micronized glyburide compositions that do not contain spray dried lactose." Id. at 1377. Thus, the court did not reach the issue of whether anhydrous lactose is the equivalent of spray dried lactose.  Owing to the fatal use of "critical" during prosecution, Pharmacia's equivalency argument fell on deaf ears.

"Special," "Peculiar," and "Superior"

In Bayer AG v. Elan Pharmaceuticals Research Corp., 212 F.3d 1241 (Fed. Cir. 2000), the patent at issue claimed a pharmaceutical composition containing nifedipine crystals of a defined specific surface area (SSA) (emphasis supplied):

  1. A solid pharmaceutical composition comprising as the active ingredient an effective amount of nifedipine crystals with a specific surface area of 1.0 to 4 m2/g, in admixture with a solid diluent, to result in a sustained release of nifedipine.

Bayer asserted that Elan infringed its patent. However, the district court disagreed, noting that Elan's ANDA specified that the proposed product would have an SSA greater than 5 m2/g, and the claims were limited to nifedipine crystals having an SSA within the range of 1.0 to 4 m2/g. Id. at 1247. The Federal Circuit agreed with the district court, noting that throughout the prosecution history, Bayer asserted that they were claiming "a special form of nifedipine, namely having a specific surface area of 1.0 to 4 m2/g," which was a "superior inventive range." Id. at 1252 (emphasis added). Additionally, the Federal Circuit noted that Bayer had argued that nifedipine crystals with this SSA range provided a "peculiar" effect of maintaining a high blood level of nifedipine for a long period of time. Id.  In the face of such patent profanity, the Federal Circuit, therefore, affirmed the district court's finding of noninfringement.

"Very Important"

The patent in Inpro II Licensing, S.A.R.L. v. T-Mobile USA, Inc., 450 F.3d 1350 (Fed. Cir. 2006) was directed to novel personal digital assistant (PDA) modules that were designed to overcome various drawbacks and problems associated with previously available PDA systems. The broadest claim at issue read:

Claim 34. A digital assistant module that interfaces with a host computer, comprising: an on-board CPU that manages functions of the digital assistant module; ...; a host interface adapted so as to provide communications between the digital assistant module and the host computer upon docking with the host computer; and an enclosure that houses said CPU, said memory, said display, said input apparatus, and said host interface. (emphasis added)

The district court construed the term "host interface" as a "direct parallel bus interface." Id. at 1353.

Appellants stipulated that a parallel bus interface was missing from the accused infringing device, but argued on appeal that the specification of the patent did not limit the "host interface" to only a parallel bus interface, and instead contemplated other types, such as serial and even indirect connections. However, the Federal Circuit disagreed, noting that the specification described a "direct parallel bus interface" as a "very important" feature of the disclosed PDA system. Id. at 1355.

Since the appellants stated that the "direct parallel bus interface" was "very important," the Federal Circuit concluded that the district court had correctly determined that the specification characterized the "direct parallel bus interface" as necessary to provide "direct" access for fast communication. Thus, the Federal Circuit affirmed the district court's ruling of noninfringement, with yet another claim biting the dust due to patent profanity:

Takeaway Lessons

As shown in the cases described in this article, the Federal Circuit has narrowly construed claims based on absolute characterization language used in the specification and prosecution history. When possible, it is recommended that drafters carefully consider the implications of patent profanity and, if using it, do so deliberately: avoid profanity for some embodiments in order to create broad claim scope and catch those who attempt to design around a patent, and then use patent profanity to define a narrow claim scope position that may be useful for patentability/validity. Carefully drafted specifications can create highly valuable patents and prevent loss in the future.

For those patent drafters involved in multi-jurisdiction prosecution in the U.S. and Europe, however, the resulting applications may not meet the requirements of both patent offices. For example, attempting to avoid patent profanity in the U.S. by using the phrase "in one embodiment" may cause added subject-matter headaches when amending claims during prosecution at the European Patent Office. If a practitioner defaults to using "the invention is" or phrases of similar ilk, it would be good, for both European and U.S. purposes, to provide clearly alternative embodiments free from the shadow of such phrases.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.