TY - JOUR
AU1 - Gavaraskar, Kirti, N
AU2 - Kulkarni,, Mohan
AB - The authors Kirti Nitin Gavaraskar is affiliated to the Academy of Scientific and Innovative Research, along with Dr Mohan Kulkarni at the CSIR-Unit for Research and Development of Information Products, Pune, India. This article The claim definiteness requirement for patentability is spelt out in paragraph b of the 35 USC section 112, which states ‘the specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or the joint inventor regards as his invention’. The US Manual of Patent Examining Procedure provides guidance for examining the definiteness of claim language employing words of degree, subjective terms, technical terms and measurement methods, conditions and descriptors. In this communication, we have analysed the cases from pharmaceutical art, to investigate whether the use of relative terms jeopardizes definiteness of claims. We analysed how these terms were classified in the literature as well as in judicial opinions to ascertain if there exists a bright line rule to decide when the claims containing relative terms are definite or otherwise. This analysis investigation led to the conclusion that relative terms are not only the terms leading to claim definiteness but also the technical terms or for that matter, any other term whose meaning is not clear could lead to indefiniteness. Although the methodology for analysing the definiteness of terms/phrases in a particular category was different, the standard to meet the claim definiteness requirement remained the same. We also enlist the ways in which the patentee could provide necessary support to successfully meet the claim definiteness challenge when using such terms/phrases. In US patent law, the definiteness requirement for the claim set forth in 35 USC section 112(b) states: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. The primary purpose of this requirement is to ensure that the scope of the claims is clear so that the public is informed of the boundaries of what constitutes infringement of the patent. Another purpose is to provide a clear indication of what the applicants regard as the invention so that it can be determined whether the claimed invention meets all the criteria for patentability and whether the specification meets the criteria of 35 USC section 112(a) or pre-AIA 35 USC section 112, first paragraph with respect to the claimed invention.1 In order to claim priority, most patents for inventions are filed when the technology is at a nascent stage. To establish the scope of such patent claims with reasonable certainty, the patentee must select both appropriate terms and capture every nuance of the invention. Often the invention is so novel that words may not always exist to describe it. As a result, the scope of the invention may not be fully captured in words and the applicant may need to rely on a series of drawings, examples or structures. How to ascertain what justifiably belongs to the patentee in view of the limitations of the language was explained by the US Supreme Court in its Festo decision.2 On the other hand, there might be situations where the boundaries of the claim cannot be precisely delineated or the patentee wishes to have some leeway in view of the nature of the invention and chooses to use relative terms in claiming the invention. The usage of such terms when necessitated by the nature of the invention would still define the boundaries of the invention with reasonable certainty to render the claim definite under 35 USC section 112(b). However, when it seeks to unjustifiably broaden the scope of the claim by obfuscating the claim boundaries, the claim be held indefinite. The challenge is to distinguish between the two situations. In this article, we show that the public notice function mandated by 35 USC section 112(b) provides the guidance needed. Various research scholars have differing opinions on this issue. Chiang and Solum proposed that ‘problem with patent claims is not the language or words therein, but the fact that there is no clear common policy amongst judges for constructing patent claims’.3 Khoury argued that a language-based construct of patent claims mostly explains why the patent system is broken.4 However, beyond the claim language, another problem that leads to the indefiniteness of a claim is drafting a claim that is sufficiently narrow as to avoid the prior art but broad enough to include future improvements in the invention. To achieve this, words such as ‘about’ and ‘substantially’ are incorporated in the claim and often fail to define the boundaries of the claim precisely. The Manual of Patent Examining Procedure (MPEP) of the United States Patent and Trademark Office (USPTO) provides guidance for examining the definiteness of claim language employing certain type of terms. These terms are classified as below: Words of degree/ term of degree (1.1) Approximations (eg about, substantially, etc) (1.2) Amounts limitations (eg effective amount and therapeutically effective) Subjective terms (eg visually distinguishable) Terms of art (3.1) Compound name or structure claims (3.2) Technical terms The category ‘terms of art’ encompasses compound names or structure of the molecule and technical terms, which represent the current state of the art in a particular field by virtue of being part of technical and scientific writing. Words of degree and subjective terms are collectively known as relative terms and are often criticized for claim indefiniteness. The scholarly literature provides guidelines to overcome the indefiniteness in patent claims, which are mostly restricted to use of words of degree or subjective terms. There are differing opinions by various researchers about the use of these types of terms. Stark5 proscribed the use of approximations such as ‘substantial’ unless explicitly defined in the body of the specification. He compared the use of the term ‘substantial’ by the patentee across cases from various technology domains. Results revealed that no uniform meaning was attributable to the term ‘substantial’. Since a flexible term may pass through the patent prosecution stage unnoticed or given little consideration, but might jeopardize validity during litigation, Stark advised against use of such amorphous terms in a patent. Dilworth emphasized the use of terms such as ‘about’ or ‘substantial’ to prevent would-be competitors from attempting to design around.6 Inventions in all fields of technology are protected by patents. While the patentability requirements under sections 102, 103 and 112(a) USC are the same for all, the threshold disclosure in predictable arts is different than that for unpredictable arts. This issue has been discussed widely in the literature with respect to sections 102, 103 and 112(a).7 The degree and extent of guidance relating to drafting claims in unpredictable arts is required to be more detailed and precise to ascertain the scope of the claims. In this article, we analyse cases from the pharmaceutical art to investigate whether the use of relative terms jeopardizes definiteness of claims. We begin our analysis by looking at how the courts classify a particular term as word of degree, subjective term or just a term of art and note that this depends on the facts and circumstances of the case. The same classification has been adopted in the past in the literature. We then present our analysis of decisions of the Federal Circuit in cases challenging the definiteness of claims containing such phrases. It is shown that while the court’s methodology for analysing the definiteness of phrases in a particular class is different, the standard to meet the claim definiteness requirement remains the same. A claim is definite if appropriate support to ascertain the meaning of terms/ phrases used in the claim is provided in the specification as mandated by 35 USC section 112(b). This is no different than the use of any other phrase needs to fulfil. The only precaution that a patentee therefore needs to exercise during drafting is to ensure that this support is provided in the specification irrespective of the classification adopted by the courts. Finally, we enlist the ways in which the patentee could provide necessary support to successfully meet the claim definiteness challenge when using such terms/phrases. Research methodology We identified the pharmaceutical cases, where the validity of the claims was challenged on the grounds of indefiniteness. A search strategy was designed based on keywords and concepts to identify indefiniteness litigations in the pharmaceutical sector at both district court and Federal Circuit levels, from the CaseText® database. Litigations involving biopharmaceutical products have been excluded from the scope of this study. Around 80 cases were studied to (i) examine occurrence of different type of terms/phrases belonging to each type and (ii) understand when and why were these held definite or otherwise under 35 USC section 112(b). The results of 22 representative cases are discussed here. Results and discussion Claim indefiniteness in pharmaceutical patents arises due to: impermissible combining of product and process claims, lack of antecedent basis, lack of disclosure of supporting structure in the specification for means plus function claims use of words of degree, lack of explicit mention of a particular method of measuring claim parameter, missing unit of expression for numeric range, use of subjective and nonsensical terms. However, in the majority of the pharmaceutical patent litigations, indefiniteness issue mainly arises due to ambiguity in claim scope resulting from the use of subjective terms, words of degree and incoherent terms of art. Words of degree and subjective terms At the outset, it is important to understand the difference between words of degree and subjective terms. Whether a term would be considered as subjective term, word of degree or term of art depends on the way it is used in the patent and also on indefiniteness grounds purported by the opponent to invalidate the patent. In Andrulis Pharmaceuticals Corp v Celgene Corp,8 the meaning of the term ‘enhanced’ was disputed. US Patent No 6,140,346 (the ′346 patent) was related to the treatment of cancers using methods and combinations that included thalidomide and other agents. The asserted Claim 2 of the ′346 patent read: A method for the treatment of neoplastic diseases in a mammal which comprises administering to said afflicted mammal enhanced therapeutically-effective amounts of thalidomide in combination with effective amounts of other alkylating agent selected from the group consisting of mechlorethamine, cyclophosphamide, ifosamide, melphalan, chlorambucil, busulfan, thiotepa, carmustine, lomustin, cisplatin, and carboplatin wherein said neoplastic diseases are sensitive to said enhanced combination (emphasis added). The disputed term ‘enhanced’ was introduced in the claim language during prosecution in response to an examiner advising that claims concerning drug combinations ‘directed to a showing of greater than additive effect’ would overcome prior art. Therefore, according to Andrulis, ‘enhanced’ was used for the specific purpose of clarifying that the claimed combination shows ‘greater than additive effect’. Celgene instead argued that ‘enhanced’ was a word of degree, but the patent never defined whether the claimed enhancement was less than additive or greater than additive. The district court stated that according to its common usage, it meant to improve, increase or intensify. The court further stated that in the medical field, a synergistic effect meant an effect relating to two or more agents that have a combined effect that was greater than the sum of their individual effects. The central issue was whether ‘enhanced’ meant greater than additive and was definite or whether it rendered the claim indefinite. Unlike ‘synergistic’, it was not apparent what ‘enhanced’ as a general term meant to a person of ordinary skill in the art. Andrulis's expert opined that ‘in light of the specification and prosecution history’, a person of ordinary skill would understand it to mean ‘synergistic’. In contrast, Celgene's expert opined, ‘that a person of ordinary skill would interpret the term “enhanced” to encompass all degrees of enhancement, including less than additive, additive, and synergistic enhancement’. The patent itself did not provide much guidance on the meaning of the term ‘enhanced’. The term showed up in the specification only twice. In one of the examples, the patent enounced that thalidomide given in combination with other alkylating agents would be expected to enhance the activity of other two agents. The court stated that expecting to enhance the activity of other two alkylating agents did not necessarily mean that result was greater than additive. Also, the prosecution history did not support Andrulis’s position. The district court accepted that the term ‘enhanced’ was added to overcome prior art, but that did not mean ‘enhanced’ was the same as ‘greater than additive’. The fact that the applicant used ‘enhanced’ rather than ‘greater than additive’ suggested that the applicant had chosen not to expressly adopt the examiner's position, as the applicant could have easily used the examiner’s suggested language. The applicant did not expressly say what was meant by ‘enhanced’. Based on common usage alone, it seemed that the applicant opted for ‘enhanced’ because it was broader in scope than ‘greater than additive’. Thus, the problem was not with the term ‘enhanced’ but with the degree of enhancement, which the court found was left unspecified in a context in which the degree of enhancement was critical. The term ‘enhanced’ was not construed to mean ‘synergistic’ or ‘greater than additive’ as those options were earlier suggested by the USPTO. The claim was held indefinite because it did not inform a person having ordinary skill in the art (PHOSITA) with reasonable certainty of its meaning.9 Had the patentee followed the examiner’s suggestion to use language ‘greater than additive’, then the question of indefiniteness would not have arisen. Also, the examples given in the specification were such that if a PHOSITA could derive that effect achieved was greater than that mentioned in the prior art, the claim could have survived indefiniteness challenge. Thus, it is very important for the specification to be self-sufficient in defining the scope of claims to PHOSITA with reasonable certainty. In Alcon Research Ltd v Barr Labs Inc,10 since the specification was adequate in explaining the scope of the claim to PHOSITA, the claim survived indefiniteness. The patents in suit, US Patent Nos 5,631,287 (‘the ′287 patent’) and 6,011,062 (‘the ′062 patent’), were related to methods of enhancing the chemical stability of prostaglandin-containing compositions by adding polyethoxylated castor oil (‘PECO’) to the compositions. The claim at issue read: A method of enhancing the chemical stability of an aqueous composition comprising a therapeutically-effective amount of a prostaglandin, wherein the method comprises adding a chemically-stabilizing amount of a polyethoxylated castor oil to the composition (emphasis added). ‘Enhancing chemical stability’ was construed by the court as increasing the ability to resist chemical change. Barr’s expert believed that the claim was indefinite for not disclosing appropriate comparator in specification as well as in claims. Although Barr’s construction did not answer the question ‘enhanced over what?’, it was clear from the claim language that PHOSITA would understand that the asserted castor oil patent claims required that using PECO in the formulation would provide increased chemical stability over those not using PECO.11 The district court held that the claim term ‘enhancing chemical stability’ could be construed and it was not insolubly ambiguous and was held valid as not indefinite. In Allergan, Inc v Teva Pharms United States, Inc,12 the same term ‘enhanced’ was treated as technical term. The US Patent Nos 8,629,111 (′111 patent), 8,633,162 (the ′162 patent), 8,642,556 (the ′556 patent), 8,648,048 (the ′048 patent), 8,685,930 (the ′930 patent) and 9,248,191 (the ′191 patent) were directed to an emulsion containing cyclosporin for treating an ophthalmic condition known as ‘dry eye’, ‘dry eye disease’ or ‘dry eye syndrome’, and a related condition keratoconjunctivitis sicca. The claim at issue recited a method of ‘enhancing tearing’ in a human eye. Other dependent claims added specific features to the composition of the claimed emulsion. In a few instances, the claim’s recited method was effective in restoring lacrimal gland tearing. Allergan argued that the terms ‘enhance’ and ‘restore’, in these patents, referred not just to an increase in the amount of tearing but also to an increase in ‘the quality of a patient’s tears’. The ordinary meaning of the ‘enhance’ was simply ‘to increase or make better’. Nothing in the claims or the specification indicated that the patents in suit have assigned the term ‘enhance’ a special meaning for these patents that differed from its ordinary meaning in the context of medical treatment. There was no issue regarding the requisite degree of enhancement of tearing, other than simply some augmentation or increase. That interpretation of the term was also consistent with the specification and the ordinary meaning of the word ‘enhance’. Since the claim could be construed with reasonable certainty, the claim was held definite. The above cases show that whether a term is treated as word of degree or technical term depends on the facts of the case and being definite or otherwise depends on the context in which it is used and sufficiency of description. In Alcon v Barr, it was unclear whether the patentee was aware of the future pitfall for the term ‘enhanced’ and drafted the patent accordingly or whether it was an afterthought during litigation. Thus, if any term is supported by the specification either by design or inadvertently and a PHOSITA could discern the meaning of the term, the claim is likely to be held definite. The only difference between assessing indefiniteness of these terms is the methodology followed to review whether claim is sufficiently supported. Since it is practically impossible for the patentee to anticipate which phrase/term would be subjected to indefiniteness challenge and how it would be treated during the litigation, the best approach is to provide the necessary support, so that the claim can survive an indefiniteness challenge. Despite a long history, there has always been uncertainty in patent law as to the proper procedure for determining the meaning of claim terms and thereby giving legal effect to that meaning. The notice function of the claims is imperative while assessing indefiniteness, as inadequate notice can jeopardize investments in innovation by subjecting investors to the unavoidable risk of infringement and litigation. Learnings from the courts’ interpretation of relative terms to ascertain claim definiteness will help draft claims, which can survive the challenge. Since majority of the indefiniteness challenges were based on use of words of degree, the following section presents cases litigated for use of words of degree. Words of degree Words of degree are those terms which modify the degree of something. Words of degree such as ‘about’, ‘approximately’, ‘substantially’, ‘effective amount’ and/or ‘therapeutically effective amount’ are prevalent in pharmaceutical patents and have led to the majority of litigation. These terms are commonly found in issued patents, and there is no general consensus that the use of such terms renders the claims indefinite.13 The Federal Circuit in Seattle Box Co v Indus Crating & Packing, Inc,14 while addressing the issue, advocated that ‘when a word of degree is used the trial court must determine whether the patent's specification provides some standard for measuring that degree, ie whether PHOSITA would understand what is claimed when the claim is read in light of the specification’. While deciding the definiteness and scope of a claim involving such words of degree, the Federal Circuit in Andrew v Gabriel has held that ‘words of degree are as precise as the subject matter permits’.15 The phrase ‘subject matter permits’ implies whether the nature of the invention and the manner in which it is described meet the requirements of the section 112(b). Approximations In patents, approximations are liberally seen preceding dosage ranges, concentration ranges or to show insignificant differences between two compositions or drug release profiles or equivalency to claimed parameters depending on how they are used in the claims. There are certain benefits and risks associated with the use of approximations. The cautious competitor reading the claim may take a broader view of the claims to avoid potential infringement. It also offers broader claim scope to encompass literal infringement. Simultaneously, it also poses risk of invalidation due to uncertain scope in presence of closer prior art. MPEP provides little guidance on how to evaluate these approximations for compliance with section 112(b) and states that words of approximation are acceptable if one of ordinary skill in the art would understand what is claimed in light of the specification. Yet, it is common for an examiner to reject a claim under section 112(b) based on the use of a word, which implied approximation. In this section, we will discuss words of degree, which have been frequently challenged for indefiniteness in litigation. About The word ‘about’ plays an important role in patent drafting when the patentee seeks to avoid the specific numerical boundary to the specified parameter. The range attributed for the word ‘about’ depends on the context in which it is used. This section presents different situations where a claim was challenged for indefiniteness for using the term ‘about’ and strategies to overcome it. A claim could be held invalid for indefiniteness in the following situations: (i) amendment of claim by adding ‘about’ to define the scope beyond what was originally stipulated, (ii) amendment of claim to avoid obviousness rejection in the presence of close prior art, (iii) use of additional modifying language such as ‘at least’, ‘less than about’ and ‘more than about’. In Ortho-McNeil Pharmaceutical v Kali Laboratories,16 in an effort to save the claim for indefiniteness, the claim failed for non-obviousness. Ortho-McNeil Pharmaceutical, Inc. (‘Ortho’) owned US Patent No 5,336,691 (the ′691 patent) directed to pharmaceutical compositions comprising certain weight ratios of two known analgesic drugs: tramadol and acetaminophen. The ′691 patent disclosed that at certain weight ratios, the composition exhibits synergistic pharmacological effects. Claim 6 of the ′691 patent was directed to a pharmaceutical composition comprising a tramadol material and acetaminophen in a weight ratio of ‘about 1:5’. Kali Pharmaceutical Laboratories (‘Kali’) filed an abbreviated new drug application (ANDA) indicating its intent to make and sell a composition containing tramadol and acetaminophen with an average weight ratio of 1:8.67. Ortho filed suit for infringement of Claim 6 of the ′691 patent. Kali also sought summary judgment on its additional invalidity counterclaims of indefiniteness and obviousness. Claim 6 as stated above read: A pharmaceutical composition comprising a tramadol material and acetaminophen, wherein the ratio of the tramadol material to acetaminophen is a weight ratio of about 1: 5 (emphasis added). The parties disputed the meaning of the limitations ‘about 1: 5’. Ortho–McNeil argued that ‘about 1: 5’ encompassed at least 1:3.6 to 1:7.1, the range of ratios representing the statistical variation in efficacy of 1:5. Kali argued that using ‘about’ to increase the range would render the claim indefinite. Based on the animal testing data in the specification and expert testimony, Ortho demonstrated that ‘about 1: 5’ weight ratio was statistically indistinguishable from a range of 1:3.6 to 1:7.1. The specification explained how the animal testing was performed and presented the test data. The mice were administered the combination composition in the weight ratio 1000:1, 1:1, 1:5 and 1:5.7. Each weight ratio was tested using different dosages of the drugs. Using the resulting data, the inventors then statistically estimated amount of tramadol and acetaminophen to be administered for 50 per cent of the 30 test mice to experience pain relief at each particular weight ratio (ED50). Since each weight ratio was tested on 30 mice, to represent the uncertainty of results in testing on infinite number of population, Ortho plotted the 95 per cent confidence interval of each weight ratio’s ED50 values. The 95 per cent confidence intervals for the 1:5 weight ratio's ED50 value (4 mg tramadol/19.8 mg acetaminophen) were 3.3–4.7 mg of tramadol, and 16.7–23.4 mg of acetaminophen. The low end of the ratio range was determined by combining the lowest acetaminophen weight, 16.7 mg, with the highest tramadol weight, 4.7 mg. This combination resulted in a weight ratio of 1:3.6 and the high end obtained was 1:7.1. Thus, a person having ordinary skill in the art of analgesic drugs reading this data would have come to the conclusion that ‘about’ encompassed this ‘statistical variation in efficacy’ of the 1:5 weight ratio and, therefore, ‘about 1: 5’ would not be statistically different from a ratio up to and including 1:7.1 and a ratio down to and including 1:3.6. Since the methodology followed by Ortho was not novel in the pharmaceutical industry, the court concluded that this range of ratios offered a sound basis, grounded in the patent specification, for measuring the full breadth of ‘about 1: 5’ and, therefore, the claim was not held indefinite. However, the Flick patent disclosed a pharmaceutical composition comprising tramadol and acetaminophen, sans claimed weight ratio, and Sorge, Beyer (Current Understanding of the Origination and Treatment of Pain, The Surgeon, July 1990) and Senn (The problem of pain in oncology, Swiss Journal of Medicine, August 1990) disclosed only the co-administration of tramadol and acetaminophen, but in weight ratios of 1:5 to 1:20. Combining these prior arts, Claim 6 was found obvious over Flick in view of Sorge, Beyer and Senn references. Thus, the court held that Claim 6 was invalid for obviousness. If Ortho could present evidence of superior results such as showing faster onset of action, longer lasting analgesia or fewer side effects due to less use of tramadol than presented in the prior art, the claim could have survived obviousness as well. For instance, in Allergan v Teva,17 the claims recited that cyclosporin A was present in an amount of about 0.05 per cent by weight of the composition and castor oil was present in an amount of about 1.25 per cent by weight of the composition. The prior art Ding patent revealed the same weight ratios 0.04 for active, cyclosporine A, but the total dosage was four times that disclosed in the patent. The Ding I patent contained four examples, the first two of which contained multiple formulations drawn from the disclosed and claimed ranges of components. The individual embodiments in Example 1 included amounts of cyclosporin varying between 0.05 per cent and 0.4 per cent, and amounts of castor oil varying between 0.625 per cent and 5 per cent. Example 1D in the Ding I patent contained 0.1 per cent cyclosporine and 1.25 per cent castor oil, while Example 1E contained 0.05 per cent cyclosporin and 0.625 per cent castor oil. Example 1B had a cyclosporin-to-castor oil ratio of 0.04, ie 0.2 per cent cyclosporine and 5.0 per cent castor oil. Since, during prosecution, the patentee had emphasized the surprising results achieved with less amount of actives, the claim survived the obviousness challenge. Thus, attention should be given to the criticality of the numerical limitation, to determine how far beyond the claimed range, term ‘about’ extends the claim scope.18 Amgen, Inc v Chugai Pharmaceutical Co, Ltd19 presents an exactly opposite situation, where while avoiding invalidation for obviousness, the claim failed for definiteness. In this case, the word ‘about’ was coupled with additional modifying language such as ‘at least’, ‘less than about’, ‘more than about’, etc. Genetics Institute and Chugai Pharmaceuticals owned US Patent No 4,677,195 (the ′195 patent) covering both a non-recombinant method for purifying erythropoietin and compositions of highly purified erythropoietin. The relevant claim at issue was: Homogeneous erythropoietin characterized by a molecular weight of about 34, 000 daltons on SDS PAGE, movement as a single peak on reverse phase high performance liquid chromatography and a specific activity of at least about 160, 000 IU per absorbance unit at 280 nanometers (emphasis added). The district court held Claims 4 and 6 of the ′195 patent invalid because their specific activity limitation of ‘at least about 160, 000’ was indefinite. Genetics Institute, one of the co-defendants, challenged this ruling, asserting that there was no evidence that Claims 4 and 6 of the patent at issue did not comply with section 112. The district court noted that ‘bioassays provide an imprecise form of measurements with a range of error’. Given this, the district court found the use of the term ‘about 160, 000 IU/AU’, coupled with the range of error already inherent in specific activity limitation, served neither to distinguish the invention over the close prior art which described preparations of 120 000 IU/AU nor to permit one skilled in the art to know what specific activity values below 160 000, if any, might constitute infringement. Genetic Institutes (GI's) partner, Chugai itself questioned whether the specific activity value of 138 000 IU/AU, for its own product, was within the claimed coverage. The Federal Circuit further stated that in prosecuting the ′195 patent in order to overcome the anticipation by Miyake and others, which disclosed a Urinary Erythropoietin product having in-vivo specific activity limitation of ‘at least 128, 620’, GI cancelled the ‘at least 120, 000’ claims and submitted the ‘at least about 160, 000’ claim language. The Federal Circuit found that the addition of the word ‘about’ constituted an effort to recapture a mean activity somewhere between the original, albeit anticipated, value and 160 000 IU/AU. Finally, the Federal Circuit noted that nothing in the specification, the prosecution history, the prior art, the expert testimony or the inventor’s testimony of record indicated what range of specific activity was covered by the term ‘about’. In affirming the district court’s decision, the Federal Circuit cautioned that while the term ‘about’ rendered Claims 4 and 6 indefinite, it did not imply that the use of the word ‘about’ would always render a claim indefinite. 20 Thus, modifying the claim language to escape the prior art by narrowing the scope the invention could save the claim for obviousness. However, it may fall in the indefiniteness trap. The Federal Circuit in Amgen v Chugai stated that ‘when the meaning of claims is in doubt, especially when, as is the case here, there is close prior art, they are properly declared invalid’.21 However, this is not applicable as general rule. The mere presence of close prior art does not always lead to indefiniteness, as is illustrated in the following example. In Cargill, Inc v Canbra Foods, Ltd,22 Cargill sued Canbra for infringement of US Patent Nos 5,969,169 (the ′169 patent) and 6,201,145 (the ′145 patent), which were related to a non-hydrogenated canola oil that possessed superior oxidative stability and fry stability and was useful for food applications. Canbra moved for a judgment of invalidity based on indefiniteness. The claimed oil was referred as ‘IMC 130’. IMC 129 was one of the parent lines used to produce the instant oil IMC 130. Claim 1 of the ′169 patent recited: A non-hydrogenated canola oil having a polyunsaturated fatty acid content of from about 7% to about 17%, an oleic acid content of about 74% to about 80% and an oxidative stability of from about 35 to about 40 AOM hours in the absence of added antioxidants (emphasis added). During prosecution, the examiner rejected the claim for being anticipated by a European patent application, which disclosed canola oil with a fatty acid composition similar to that of IMC 130. Cargill contended that the data in the specification demonstrated that two canola oils with similar fatty acid compositions, the claimed IMC 130 oil and oil designated as IMC 129 had strikingly different oxidative stability values. Ordinary canola oil was unstable and easily oxidized during cooking, which created an off-flavour in the food. It also developed an undesirable odor when being stored. Therefore, the superior stability of the IMC 130 oil made that oil more acceptable for cooking and storage. Based on the test evidence, the examiner allowed the claims. The oxidative stability of canola oil could be measured in at least two ways: in terms of Active Oxygen Method (AOM) hours or in terms of peroxide and para-anisidine values. The claim limitation at issue concerned oxidative stability limitations: ‘about 35 to about 40 AOM hours’. Oxidative stability limitation values were preceded by ‘about’ and employed standardized test for measuring stability subject to recognized coefficient of variation. The use of ‘about’ somewhat extended the scope of the test value. Canbra Foods contended that the use of the word ‘about’ made the boundaries of the claim unclear, rendering it invalid under section 112(b). Canbra further stated that the presence of close prior art exacerbated the uncertainty. Citing Amgen, Canbra asserted that when three things are present—experimental variation in a recited numerical range, close prior art and use of the term ‘about’—the claim is deemed to be indefinite. However, the district court rejected the contention stating that the present case was different from Amgen in certain respects. First, the range of error in Amgen was significantly broader. Secondly, unlike in the present case, Amgen involved what was then a new technology without accepted industry standards of measurement and error. Thirdly, in Amgen, the measurement technique itself was imprecise; therefore, the chosen value of 160 000 IU/AU failed to distinguish the invention over the close prior art. However, in the present case, if the numerical values were given their ordinary meaning, then a person of ordinary skill in the art would have been able to determine that the IMC 129 value of 30 was distinguishable from ‘about 3.’. Amgen employed word of degree and claimed a narrower scope to escape prior art, which led to invalidation for claim indefiniteness. Canbra Foods’ motion for judgement of invalidity on the ground of indefiniteness was denied by the district court. The case substantiated that the likelihood of invalidity for indefiniteness depends on the intent of the patentee whether to broaden the scope or narrow it to escape prior art, and the status of technology (whether it is well established or nascent). Another issue is the use of words of degree with modifying language, such as ‘at least’, ‘greater than’ or ‘not more than’. In Amgen, the use of the modifier ‘at least’ preceding term ‘about’ exacerbated the uncertainty. Therefore, a PHOSITA could not discern how much below the 160 000 value was being claimed. Use of ‘about’ along with modifying language would lead to fatal situations as illustrated by the following cases. In Kimberly-Clark Worldwide v First Quality Baby Products,23 the Kellenberger patent concerned an absorbent composite or core for an absorbent article, consisting of a matrix of fibers and superabsorbent material that was designed to absorb fluids, dramatically reducing the thickness and weight of an absorbent article. The Melius patent advanced the technology of Kellenberger by increasing the concentration of superabsorbent within the absorbent composite and provided a method and procedure for evaluating superabsorbent materials. US Patent Nos 5,147,343 (‘Kellenberger Patent’) and 5,601,542 (‘Melius Patent’) contained the claim terms ‘at least about’ and ‘less than about’ in various combinations (Claims 1, 8, 9, 20 and 41 of the Kellenberger Patent contained the phrase ‘at least about 50%, by weight, of said superabsorbent material’. In addition, Claims 8 and 9 further provided, respectively, that the superabsorbent material ‘has a particle size of at least about 100 microns’ and ‘has a particle size of at least about 150 microns’. Similar to the Kellenberger Patent, Claims 18, 19, 65, 71, 74, 79, 84 and 88 of the Melius Patent also contained the phrase ‘at least about’, and Claims 16, 22–24, 64, 69, 73, 78, 83 and 88 contained the additional phrase ‘less that about’. Kimberly-Clark (‘KC’) contended that ‘less than about’ meant ‘less than approximately’, and that ‘at least about’ meant ‘equal to or greater than approximately’. These terms included the above-mentioned modifying language in conjunction with a numerical value. First Quality asserted that the claim terms were indefinite because each term contained modifying language followed by a numeric value that prevented one skilled in the art from determining the scope of the claim terms. There was no intrinsic evidence that the word ‘about’ coupled with ‘at least’ had an accepted meaning. The specification did not provide for a numerical range or a statistical deviation that would explain the scope of the claims. For example, a competitor had no way of knowing how far below 50 per cent by weight would be considered infringing. Also, the KC’s expert opinion was unhelpful because it failed to support his opinion with any intrinsic or extrinsic evidence that would indicate how he concluded that a person skilled in the art would readily understand the terms. KC further argued that the use of this language allowed some flexibility in the analysis of the claim for the trier of fact to assess whether a particular weight percent was covered by the claim. This statement directly contradicted the purpose of the definiteness requirement, which demanded that a claim term place the public on notice of what the patent excluded. Although the courts, including the Federal Circuit in various cases, had defined ‘about’ to mean ‘approximately’, the district court in this case agreed with First Quality that ‘about’ when coupled with ‘at least’ did not sufficiently inform the public of what would infringe. Consequently, the claim term was held indefinite and the claim invalid. In Synthes (USA) v Smith Nephew, Inc,24 the claims of US Patent No 5,053,036 recited the ‘bone contact area’ or the ‘studs for bone contact’ to be ‘less than about 2%’ of the lower surface of bone plate. Smith argued that there was no way of determining what numerical values would fall within the ambit of ‘about 2%’ and, also, that there was no way of knowing what percentages were ‘less than’ that amount, and thus no way of knowing whether a competing product was infringing. The ratio of the studs or bone contact area to the area of the plate's lower surface was a crucial aspect of the invention. which was directed specifically towards a plate that minimized bone contact. The phrase ‘less than about 2%’ was clearly directed at that essential feature, yet it was impossible to tell exactly what constituted ‘about 2%’. There was no intrinsic evidence to support that the word ‘about’, when applied to the ratio of studs-to-plate surface, would define the scope of the claim; nor was the range provided for the ratio cited. Synthes failed to offer any explanation or testimony by experts as to why the words ‘about 2%’ was used, especially when other claims in the patent and the written description in the specification omitted the vague ‘about’ and simply recited a ratio of ‘less than 2%’. Thus, the claim containing term ‘less than about 2%’ was held indefinite as it did not adequately notify the public of the patentee's right to exclude. The scope of the term ‘about’ coupled with modifying language could be ascertained in certain situations by providing numerical range or statistical deviation. In Graceway Pharmaceuticals, LLC v Perrigo Company,25 the patent claimed that a pharmaceutical cream for topical application comprised imiquimod (an immune response modifier) and oleic acid. Claims 1, 7 and 13 recited that the cream was comprised an ‘oleic acid component, wherein the oleic acid component at or prior to formulation … contains at least about 80% oleic acid by weight as a fatty acid’ (emphasis added). The parties disputed that the phrase ‘at least about 80%’ in regard to the oleic acid components was indefinite. The defendant, Nycomed, argued that a person of ordinary skill in the art would not know if the lower bound of at least about 80 per cent is 79.5 per cent, 79 per cent, 75 per cent or some other amount altogether. Graceway Pharmaceuticals countered by stating that ‘at least about 80%’ would have been understood by one of ordinary skill in the art to have permitted ‘up to a 10% deviation’ from the claimed amount of 80 per cent, therefore, at least about 80 per cent oleic acid means ‘at least 72% oleic acid’. The question was purely of summary judgement, ie whether or not the evidence submitted by the parties in support of and in opposition to the motion establishes a genuine issue of material fact. The defendant’s prior filing with the court and materials Nycomed exchanged with Graceway (Non-Infringement Contention Disclosure) in contemplation of Markman proceedings demonstrated that Nycomed could construe the meaning of ‘at least about 80%’. Therefore, the defendant’s motion for summary judgement on the ground of indefiniteness was denied by district court. These cases suggest that where ‘about’ is coupled with modifying language, it renders those claims open ended. Therefore, it becomes difficult to decide the actual scope covered by the use of that claim term. This can be avoided if the intrinsic evidence informs public about the scope of the claim limitation intended. If the nature of the invention is such that this double uncertainty arising from the use of ‘about’ coupled with modifying language is unavoidable, a careful drafting of the specification is required. This can be done by providing numerical ranges or statistical deviation as the subject matter of the invention permits. In certain situations, the scope of the claim limitation including term ‘about’ would be evident, even when the numerical range or statistical deviation is not quoted. For instance, in Chiron Corporation v Sourcecf Inc,26 in spite of giving ‘about’ its ordinary and customary meaning ‘approximately’, it served the public notice function correctly and the claim was held definite. Chiron corporation owned a US Patent No 6,890,907 (the ′907 patent) disclosing method of treating lung infections with inhalation formulation containing tobramycin for treating patients with cystic fibrosis. The claim at issue read: A method of treatment of a patient having an endobronchial infection comprising administering to the patient for inhalation a nebulized unit dose of 4.0 ml or less of an aqueous solution comprising from about 60 to about 200 mg/ml of tobramycin in a physiologically acceptable carrier for a duration of nebulization less than about 10 minutes, using an inhalation device having a rate of aerosol output of not less than about 4 μl/sec, that releases at least about 75% of the loaded dose, and that produces aerosol particles having particle sizes between about 1 μm to about 5 μm (emphasis added). In deciding the limits imposed by term ‘about’, Sourcecf asked the district court to find that an aqueous solution of 50 mg/ml of tobramycin in a physiologically acceptable carrier would be excluded from the range ‘about 60 to about 200 mg/ml’. Alternatively, Sourcef also contended that if the issue could not be resolved, then the patent should be deemed invalid as indefinite. The district court found that the specification never addressed concentrations of tobramycin of less than 60 mg/ml. On the contrary, the specification repeatedly referred to a concentration involved as 60 mg/ml or above. The studies shown in the ′907 specification were tested for concentrations of 60 mg/ml or higher (120 mg/ml). The district court stated that nowhere in the specification did the inventor expressly defined about 60 mg/ml to mean at least 60 mg/ml or exactly 60 mg/ml or anything other than the ordinary or customary meaning as understood by the person of ordinary skill in the art. Accordingly, the court held that ‘about 60 to about 200 mg/ml’ had to be construed as ‘approximately 60 to about 200 mg/ml’. The specification further mentioned that a dose lower than 60 mg of tobramycin of diluted saline was not sufficient to suppress the bacterium and to treat the infection. It further stated that lower concentrations of tobramycin would not be sufficiently effective in at least 90 per cent of patients. Thus, even under the doctrine of equivalents, 50 mg/ml concentrations in dispute did not infringe the ′907 patent. In Allergan Sales, LLC v Lupin Ltd,27 Allergan sued Lupin for infringing US Patent Nos 8,008,338 (the ′338 patent), 8,207,215 (the ′215 patent) and 8,377,982 (the ′982 patent). The representative claim at issue read: A method of treating ocular pain in a person, the method comprising the step of administering at least once daily to an eye of the person a first composition comprising about 0.4% w/v ketorolac tromethamine, wherein the method reduces ocular pain and results in less ocular side effects as compared to the at least once daily administration to an eye of a second composition comprising 0.5% w/v ketorolac tromethamine (emphasis added). The dispute centered around the meaning of ‘about 0.4% w/v ketorolac tromethamine’ and ‘about 0.4% w/v ketorolac’. These phrases were found in Claims 1, 3, 10 and 12 of the ′982 patent. Allergan argued that the term ‘about’ was readily understood by one skilled in the art according to its plain and ordinary meaning. Allergan further contended that the term should be construed as ‘approximately’ and cited several district court and Federal Circuit cases construing ‘about’ to mean ‘approximately’. Lupin contended that during prosecution of the earlier issued ′338 and ′215 patents, the patentee had presented claims with a range of ‘from 0.35% w/v to 0.45% w/v’ of Ketorolac Tromethamine but then amended the claims to recite ‘0.4%’ in the face of obviousness rejection. Lupin argued that the inclusion of ‘about’ in the later issued ′982 patent was an attempt to recapture that claim scope to some degree, however, that degree was unclear and, therefore, the claims were indefinite. The court observed that where disclaimers made during prosecution are directed to specific claim terms that have been omitted or materially altered in subsequent applications, such disclaimers do not apply to the later patent. It further stated that the specific claim term ‘from 0.35% w/v to 0.45% w/v’ did not appear in the ′982 patent and, therefore, no indication that the term ‘about 0.4% w/v’ had the same meaning or scope as ‘from 0.35 w/v to 0.45% w/v’. Accordingly, the court declined to find that a disclaimer of ‘from 0.35% w/v to 0.45% w/v’ from earlier prosecuted applications carries forward to the ‘about 0.4% w/v’ limitation in the ′982 patent. The court interpreted the term ‘about’ according to its plain and ordinary meaning as ‘approximately’ and held the claim definite. Thus, a careful analysis of cases challenged for inclusion of term ‘about’ reveals that the scope of ‘about’ is always decided in light of intrinsic evidence. In the presence of close prior art, claim definiteness and obviousness challenges appear related. Therefore, it is important to pay attention to both the grounds of invalidity when defining the scope covered by ‘about’. When ‘about’ is used along with language such as ‘less than’, ‘more than’, ‘at least’ or ‘greater than’, the Federal Circuit as well as district courts have rejected the claim as indefinite. Therefore, the patentees should try to avoid such language unless sufficient evidence in terms of examples is presented in the specification to determine lower or upper limits covered by such open-ended language. Whether such language in a patent would withstand an indefiniteness attack depends on the facts and circumstances of each case, and, in particular, whether the patent, or the intrinsic or extrinsic evidence, provides guidance such that a person of ordinary skill in the art could determine the metes and bounds of the invention claimed. Substantially Term ‘substantially’ has been used extensively in the patent documents. When the term ‘substantially’ is used, no numerical limitation is imported into claim language and the courts consider possible deviations from absolute. As a result, the claimed device/method has been held novel/non-obvious in most of the cases. Judge Hand in Musher Foundation v Alba Trading Co, Inc noted that ‘the term “substantially” must always be implied in every claim, even when not introduced, and adds nothing when it is’.28 In Amhil Ent v Wawa, Inc, the patentee used the term ‘substantially vertical’ interchangeably with ‘vertical’ both in the specification and during prosecution. The court ruled that the two terms were essentially the same, although Judge Hand’s ruling was not used as standard rule of claim construction.29 In Actavis Labs UT, Inc v UCB, Inc,30 Actavis alleged infringement of US Patent No 7,921,999 (the ′999 patent). The ′999 patent was directed to peel-open packaging for a transdermal patch. The term ‘substantially’ was used to describe the flatness of enclosures formed by opposing plies of the pouch in its claim: A peelable pouch system for holding a transdermal patch, comprising: a substantially flat enclosure formed by first and second opposing flexible plies; a seal, extending along at least a portion of a perimeter of the opposing plies and coupling the plies to one another; a flat, flexible transdermal patch, disposed in the enclosure, the patch including an adhesive layer with a bioactive agent therein, the adhesive layer disposed between a backing layer and a removable release liner; the patch being rigid so as to at least partially resist bending and being resilient so as to return to a substantially flat orientation after being bent out of the flat configuration; the first and the second plies each being separable along the seal and displaceable out of the flat configuration. Actavis stated that the meaning of ‘substantially flat orientation’ was understood in the context of the patent's teaching regarding the term ‘substantially’. The specification also taught that ‘substantially’ referred to complete or nearly complete extent. UCB contended that it was unclear from the patent what level of flatness constitutes ‘substantially flat’. The district court held that ‘substantially flat’ was a term of degree that was sufficiently explained in the patent and a patch would be ‘substantially flat’ when it is flat enough to have the overall same effect on space for packaging and shipping as it did in its original flat configuration. ‘Substantially’ was used to denote a characteristic or property that had overall same result as if complete. The court assigned the ordinary and customary meaning to the term and held the claim valid as definite. In this case, one of the ordinary skills in the art would have understood that the pouch and patch need not be perfectly flat and the claims were directed to features of the pouch system, not to steps for operating the system. The limitation was not directed to a step of performing the function or the particular condition in which the function was performed. Hence, the claim was not indefinite. Using qualifying terms interchangeably with unqualifying terms implies the same definition for both, ie using ‘flat’ interchangeably with ‘substantially flat’ led to the court ruling both terms as being essentially the same under standard tools of claim construction and holding the claim definite. Likewise, in Allergan v Teva,31 the term ‘substantially’ was used to compare the efficacy of two topical ophthalmic solutions. The patents in suit, US Patent Nos 8,633,162 (the ′162 patent), 8,642,556 (the ′556 patent), 8,648,048 (the ′048 patent), 8,685,930 (the ′930 patent) and 9,248,191 (the ′191 patent), were directed to an emulsion containing cyclosporin, a compound that is useful for treating an ophthalmic condition known as ‘dry eye’. The claim at issue read: The method of claim 1, wherein the emulsion is as substantially therapeutically effective as a second emulsion administered to a human in need thereof at a frequency of twice a day, the second emulsion comprising cyclosporin A in an amount of 0.1% by weight and castor oil in an amount of 0.5% by weight (emphasis added). The claim limitation at issue was ‘as substantially therapeutically effective as a second emulsion’ appeared in Claim 14 in the ′162 patent; Claims 1 and 13–15 in the ′556 patent; Claims 13–16 in the ′048 patent; and Claims 1, 13, 17 and 21 in the ′191 patent. The parties disputed the definition of ‘substantially’. The specification contained an example that sets forth a comparison of two emulsions, the first with 0.05 per cent cyclosporin and 1.25 per cent castor oil, and the second with 0.1 per cent cyclosporin and 1.25 per cent castor oil. The example listed other constituents of both emulsions, which were exactly the same. The court stated that the principal point of the invention was to state that the relative concentration of cyclosporin can be reduced, in an otherwise identical emulsion, without substantial loss of therapeutic effectiveness. Accordingly, the court construed the limitations to mean that the ‘first emulsion is substantially as effective in treating the underlying disease as the second emulsion’ and ‘achieves as much effectiveness/efficacy in treating the underlying disease’. In light of this construction, the court held that claims were not indefinite. In Allergan, Inc v Sandoz Inc,32 the court applied the same principle as in Amhil v Wawa while assessing the definiteness of term ‘substantial’. Allergan obtained Food and Drug Administration (FDA) approval for Lumigan® 0.01 per cent bimatoprost ophthalmic solution for the reduction of elevated intraocular pressure in certain patients, including those with open angle glaucoma or ocular hypertension. US Patent Nos 8,278,353 (the ′353 patent) and 8,299,118 (the ′118 patent) were related to Lumigan®, prostaglandin analog bimatoprost, which worked by increasing the outflow of aqueous humour from the eye. Sandoz filed an ANDA for FDA approval to market a generic version of Allergan’s Lumigan® 0.01 per cent bimatoprost ophthalmic solution. The parties disputed the definition of ‘substantial’. The court stated that although ‘substantial’ calls for an evaluation of degree, it reasonably conveyed when reduced intraocular pressure qualified as ‘substantial’. It further stated that terms not defined in the specification are not indefinite if a person of ordinary skill in the art would understand their meaning. Also, the prosecution history established that person having ordinary skill in the art would appreciate how to compare efficacy of two strengths of bimatoprost ophthalmic solutions. The court held the claim definite as ‘substantial’ meant ‘nearly equivalent’. The term ‘substantially’ can be interpreted as an approximation of precision for another term or as magnitude. The interpretation of this term again depends upon the context. This is illustrated by following cases. In Bausch Lomb Inc v Alcon Laboratories, Inc,33 Bausch alleged that Alcon infringed US Patent No 5,096,607 (the ′607 patent), which claimed an invention in a process for simultaneously cleaning and disinfecting contact lenses using a single solution. ‘Substantially’ was used in relation to the effect of cleaning enzymes on the antimicrobial activity of disinfecting solution. Bausch had claimed a method for simultaneously cleaning and disinfecting contact lenses that ‘does not substantially inhibit the activity of the antimicrobial agent’. The claim read: A method for simultaneously cleaning and disinfecting contact lenses comprising contacting the lenses with an aqueous system containing a disinfecting amount of an antimicrobial agent selected from the group consisting of polymeric quaternary ammonium salts used in ophthalmic applications and biguanides, in absence of thimerosal, and an effective amount of a proteolytic enzyme for a time sufficient to simultaneously clean and disinfect the lenses and wherein the osmotic value of said aqueous system, is adjusted to a level which does not substantially inhibit the activity of said antimicrobial agent (emphasis added). Alcon contended that absent some objective, quantifiable parameters by which to determine how effective the disinfectant powers of the solution were, the phrase ‘substantially inhibit’ rendered the claim void for indefiniteness. The court held that simply because the claims could be framed in terms of specific numbers did not mean that they had to. During re-examination proceedings, Bausch had put forward different definitions for ascertaining the scope of substantially inhibited. The court held that these different definitions put forth by Bausch need not be viewed as mutually exclusive, nor did they prove that the average person would not understand the meaning of ‘substantially inhibited’. Also, in view of the expert testimony that a person skilled in the art would understand what the phrase ‘does not substantially inhibit’ meant, and Alcon's failure to present contrary expert testimony, the court found that the claim of the ′607 patent was not indefinite. The court did not require ‘substantially’ to be accompanied by numeric boundaries. Thus, imposing mathematical precision is not always necessary, and the patentee could claim an invention in terms that would be understood by person skilled in the art. The extent of details required to be included in claims depends on the particular invention and the state of the art, and should not be viewed in abstract. In Forest Labs., Inc v Teva Pharms US, Inc,34 Forest alleged infringement of US patent No 8,039,009 (the ′009 patent) directed to a modified release dosage of form memantine (Nemada XR) for treatment of moderate to severe dementia of the Alzheimer's type. The parties disputed the scope of the term ‘substantially contributing to the modification of the release’. Claim 1 recited the following, with emphasis added to the disputed terms: A method for treating Alzheimer's disease comprising once daily administration of a modified release solid oral dosage form comprising 28 mg ±5% of memantine or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable polymeric carrier substantially contributing to the modification of the release of the memantine or pharmaceutically acceptable salt thereof, said dosage form sustaining release of the memantine or pharmaceutically acceptable salt thereof from about 4 hours to about 24 hours following entry of said form into a use environment, wherein said dosage form has a single phase dissolution rate of less than about 80% after passage of about 6 hours following said entry into said use environment. Teva asserted that the term ‘substantially’ was indefinite as it did not convey with reasonable certainty how much the ‘pharmaceutically acceptable polymeric carrier’ must ‘contribute’ to the modification of the release of memantine. Forest had not cited any intrinsic evidence that showed or explained how much any particular polymeric carrier contributed to the modification of the release of memantine. Based on the expert testimony from both the parties, the court found that a person having ordinary skill in the art would be able to decipher ‘substantially contributing’ as ‘the polymer is impacting the release’. Thus, the court held that inclusion of the term ‘substantially’ in these claims would not deprive a PHOSITA of ‘reasonable certainty’ of the meaning of the claims. Analysis of the case law makes it clear that the word ‘substantially’ is given its ordinary and customary meaning by the courts. The term can be used in patents and be held definite, so long as a PHOSITA, in light of prosecution history and prior art, would recognize its range in terms of magnitude or degree.35 In essentially all of the cases that involved the term ‘substantially’, the courts found the claim to be definite, even if the specification did not provide the special definition of the term substantially. The courts often looked at the function of the claimed device or apparatus to determine the scope of the term ‘substantially’ and no numerical limitation was imported into the claims. Thus, words of degree may advantageously be used to broaden the claim scope during enforcement and would be held definite so long as inclusion of the term ‘substantially’ in these claims would not deprive a PHOSITA of ‘reasonable certainty’ of the meaning of the claims. Subjective terms The next category of terms which is often challenged for indefiniteness is ‘subjective term’. The subjective terms are similar to words of degree in that the quantification of magnitude/degree depends on another parameter/measure. In case of words of degree, the scope of the claim term is determined by the objective standard given in the specification or prosecution history. The subjective terms differ from words of degree in that their interpretation is based on or is influenced by personal feelings, tastes or opinions. Therefore, subjective terms do not have an exact meaning; instead, their meaning relies upon the view of the person interpreting the term. Determining whether a claim meets claim definiteness requirement is easy when the issues are objective. As such, the courts have permitted subjective language in a claim, provided that the specification includes sufficient guidance as to the scope of the claims. When confronted with indefiniteness issues, the courts closely study the supporting specification, and rely heavily on the specification when determining whether subjective claim language provides adequate notice to the public concerning the metes and bounds of the claims. In Apotex, Inc v UCB, Inc,36 the patent in suit, US Patent No 6,767,556 (the ′556 patent), claimed a process for the manufacture of stable moexipril magnesium tablets for the treatment of high blood pressure. Each claim of the ′556 patent required reacting moexipril or an acid addition salt thereof ‘in the presence of a sufficient amount of solvent’ ‘for a predetermined amount of time’ and ‘in a controlled manner’, so as to convert greater than 80 per cent of the moexipril to moexipril magnesium. Claim 1 of the ′556 patent, the only independent claim, read: A process of making a solid pharmaceutical composition comprising moexipril magnesium, said process comprising the step of reacting moexipril or an acid addition salt thereof with an alkaline magnesium compound in a controlled manner in the presence of a sufficient amount of solvent for a predetermined amount of time so as to convert greater then [sic] 80% of the moexipril or moexipril acid addition salt to moexipril magnesium. (emphasis added) The claim limitations (i) ‘sufficient amount of solvent’, (ii) ‘predetermined amount of time’ and (iii) ‘controlled manner’ were challenged for indefiniteness. These terms were added to the claims during prosecution of application in order to overcome the examiner's rejections of the claims as obvious over the prior art. The remarks accompanying the amendments in which these terms were added did not provide any guidance to a person of ordinary skill in the art as to what constituted a ‘sufficient amount of solvent’, a ‘predetermined amount of time’ or a ‘controlled manner’ within the context of the ′556 patent's claims. Apotex proposed a construction of these terms in the context of trying to achieve greater than 80 per cent conversion of moexipril to moexipril magnesium during the manufacturing process, ie any amount of solvent or time would be ‘sufficient’ and any process would be ‘controlled’ if it results in conversion of greater than 80 per cent of moexipril to moexipril magnesium during the manufacturing process. However, the amount of solvent and time used in wet granulation for a drug product varies considerably based on other parameters, such as the ingredients and equipment used, temperature and drying parameters. The court found that the claims of the ′556 patent invalid as indefinite under 35 USC section 112, paragraph 2, as neither specification and the file history (i) provided any guidance to PHOSITA on how much time, solvent or what manner of control was sufficient to achieve or avoid the ‘greater than 80%’ conversion threshold required by the asserted claims, nor (ii) provided any objective test to determine whether the ‘greater than 80%’ conversion limitation was met. The claim limitations ‘Sufficient amount of solvent’ or ‘controlled manner’ might appear subjective terms at first blush. However, in this case, due to the mention of the threshold to assess ‘greater than 80% conversion’, the term qualified as a term of degree. Whether a term is subjective or a word of degree depends upon the context of the claim in which it is used. Subjective terms could be words of degree, but words of degree may not be subjective. If the applicant had mentioned the assay method to measure conversion percentage, the claim would have survived claim indefiniteness challenge. Few terms are purely subjective, such as ‘visually distinguishable’. In Re Oxycontin Litigation,37 Purdue Pharma brought action against manufacturer of generic pharmaceutical products, alleging infringement of US Patent No 7,776,314 claiming technology of making tablets resistant to abuse. Claim 1 read as follows: A parenteral abuse-proofed solid dosage form for oral administration, comprising, in addition to one or more active ingredients with potential for abuse selected from the group consisting of opiates, opioids, tranquillizers, stimulants and narcotics, at least one viscosity-increasing agent in a quantity equal to or greater than 5 mg per dosage form and such that an aqueous extract obtained from the dosage form with 10 ml of water at 25°C. forms a gel which can still pass through a needle having a diameter of 0.9 mm and remains visually distinguishable when introduced by a needle into a further quantity of an aqueous liquid (emphasis added). The scope of the claimed invention was defined through gel test. It required that the material remains ‘visually distinguishable’ at the end of the gel test. The court interpreted the term to mean material ‘remains substantially insoluble and cohesive and cannot straightforwardly be dispersed in such a manner that it can safely be administered parenterally, in particular intravenously’. The relevant art did not contain any standard for determining whether a substance is ‘visually distinguishable’, ‘cohesive’ or ‘straightforwardly dispersed’. Whether a substance is visually distinguishable or not would depend on the acuity of the vision of the person assessing the test results. Therefore, the court held the term ‘visually distinguishable’ as not amenable to any construction other than that provided by the court and even that construction did not allow court to decide on infringement. Claim 1 was held invalid as indefinite, being insolubly ambiguous. Instead of depending on the acuity of the vision of individual, providing an objective test such as light refractometry would have been definitive in the context of the invention. In the wake of above cases, it is desirable to include as much objective definition and as many concrete examples as possible which would contribute to the clarity of claim terms and reduce the likelihood of a later finding of indefiniteness. Technical terms Technical terms are defined as terms that possess a particular meaning within a particular field of expertise. A technical term used in a patent claim is interpreted as having the meaning a person of ordinary skill in the field of the invention would understand it to mean. For ‘words of degree’ and ‘subjective’ terms, there is no bright line rule about the interpretation. The same applies to technical terms, but to a lesser extent. Technical terms encompass compound names or the structure of the molecule, more specifically a polymorph38 or enantiomer39, and terms of art. ‘Terms of art’ is the terminology used to define specific words and phrases used in a particular profession, trade and/or group. It is easier to overcome the indefiniteness challenge for these kinds of terms by providing proper nomenclature for the compounds and illustrating the structure of the compound in claim. However, it is difficult to overcome the indefiniteness challenge for terms, which are part of technical and scientific writing. This section investigates what leads to claim indefiniteness for technical terms. Compound names and structure claims In Smithkline Beecham v Apotex Corp,40 Claim 1 of US Patent No 4,721,723 (the ′723 patent) covered paroxetine hydrochloride hemihydrate (‘PHC hemihydrate’), the active ingredient in the antidepressant Paxil. Apotex filed an ANDA to market paroxetine hydrochloride anhydrate (‘PHC anhydrate’) as an anti-depressant prior to the expiration of the ′723 patent. Smithkline sued Apotex for infringement of the ′723 patent. It alleged that manufacture of PHC anhydrate results in trace amounts of PHC hemihydrate because PHC anhydrate is highly unstable and morphs to more stable PHC hemihydrate.41 Thus, any attempt by the defendant to produce non-infringing paroxetine would unavoidably lead to production of at least trace amounts of the infringing crystalline form.42 The claim at issue recited in clear terms a discernible chemical structure of the hemihydrate. The district court restricted the construction of the claim to commercially significant quantity. It held that the claim language required the accused product to contain commercially significant quantity of the claimed hemihydrate. Justifying the importation of such limitation, district court held that Apotex would not be liable for infringement. On appeal by SmithKline, the Federal Circuit rejected this rationale, holding that the claim was neither broad nor narrow, but definitive of the particular chemical structure of the hemihydrate. The test for indefiniteness was whether a person skilled in the art knows the bounds of a claim for infringement and does not depend on the potential infringer's ability to ascertain the nature of its own accused product to determine infringement. In support of its decision that even if a claim was broad enough to cover undetectable trace amounts of the claimed substance, the Federal Circuit stated ‘breadth is not indefiniteness’.43 Accordingly, Claim 1 was held definite under 35 USC section 112, paragraph 2. In Ortho-McNeil Pharmaceutical v Mylan Laboratories, claim S(-) pyridobenzoxazine clearly designated the levorotatory enantiomer of ofloxacin. Mylan deliberately imported optical purity limitation justifying that the claim will be distinguishable over racemate ofloxacin in the prior art. It also contended that the lack of this explicit optical purity value for the claimed compound rendered the claim indefinite. The district court held that although PHOSITA would have understood the claim to the compound levofloxacin to be substantially pure levofloxacin, the realities of science would have led such a skilled artisan to conclude that the purity was not 100 per cent. This was confirmed by the specification. Also, the proposed optical purity calculation of Mylan’s own expert illustrated that a PHOSITA could discern the scope of the levofloxacin claim, which was amenable to construction. Therefore, the court refused to import limitation of explicit optical purity and held the claim not invalid as indefinite. Thus, inventions claiming a particular molecular structure will be valid when claimed by simply listing the proper chemical name in the claim and including the corresponding structure in the specification. Terms of art Terms of art often require peculiar knowledge and education to understand them aright.44 For example, ‘plasticizer’ is a term of art in polymer chemistry and in the plastics industry.45 As we have explained earlier, a term could be word of degree, subjective term or term of art. However, how it has been used in the patent decides its fate as to how it could be classified and how it would be handled in the case of an indefiniteness challenge. MPEP section 2173.05(b)III states that ‘one must consider the term as it is used in the specification and claims of the application’. The term ‘resilient’ is a term of art but it was treated as term of degree in Actavis v UCB.46 Ordinary and customary meaning could be ascribed to terms of art. However, in certain cases, the patentee can define these terms in the context of invention in the specification. Although the meaning ascribed by the patentee would be different from the ordinary meaning for that term, the term would likely survive indefiniteness challenge. In King Pharmaceuticals, Inc v Purdue Pharma, LP,47 the patentee exercised his right as lexicographer for the term ‘bioequivalent’ to mean ‘equivalent antagonistic effect’ and avoided rejection based on indefiniteness. The claim at issue of US Patent No 7,658,939 read: An opioid antagonist composition comprising an inert core, a first layer and a second layer, the first layer being between the core and the second layer, the first layer consisting of the opioid antagonist, and the second layer comprising a hydrophobic material, wherein the hydrophobic material sequesters the opioid antagonist such that an amount of the antagonist released from the composition which has been administered intact is bioequivalent to 0.125 mg naltrexone or less, based on the in-vitro dissolution at 1 hour of the composition in 900 ml of Simulated Gastric Fluid using a USP Type II (paddle) apparatus at 75 rpm at 37° C., and less than 15% by weight of the opioid antagonist is released within 36 hours from the intact composition, based on the in-vitro dissolution in a dissolution bath, and the composition is free from an opioid antagonist (emphasis added). The common definition of ‘bioequivalent’ used by those skilled in pharmaceutical manufacturing only applies to compounds with the same active ingredient. The court concluded that even though the typical definition used by those skilled in the art is a baseline at which to start interpreting claim terms, ‘a patentee may choose to be his own lexicographer and use terms in a manner other than their ordinary meaning’. The claim was therefore held definite as PHOSITA could understand ‘bioequivalent’ to mean ‘equinantagonistic effect’ in light of intrinsic as well as extrinsic evidences. In Reckitt Benckiser Pharms Inc v Watson Labs, Inc,48 the claim at issue was: A film dosage composition comprising: A polymeric carrier matrix; A therapeutically effective amount of buprenorphine or a pharmaceutically acceptable salt thereof; A therapeutically effective amount of naloxone or a pharmaceutically acceptable salt thereof; and A buffer in an amount to provide a local pH for said composition of a value sufficient to optimize absorption of said buprenorphine, wherein said local pH is from about 3 to about 3.5 in the presence of saliva. (Claim 1, US Patent 8,475,832 (the ′832 patent)) (emphasis added) Watson argued that the ′832 patentees could have defined the claimed pH values as those measured by dissolution testing, which was well known in the art. Instead, it used the term ‘local pH’. Expert testimony indicated term ‘local pH’ to implicate complex dynamics and measurement techniques, while Reckitt stated that the term ‘local pH’ to considered as equivalent to ‘microenvironmental pH’. However, Reckitt failed to explain how microenvironmental pH correlated to the dissolution pH testing that the experts conducted. The trial court contended that particular conditions under which pH is measured could influence the pH values. The ′832 patent did not disclose the volume of solvent that should be used to measure ‘local pH’ in in vitro dissolution tests, the type of solvent that should be used to measure ‘local pH’ in in vitro dissolution tests, or the time point at which ‘local pH’ should be measured in in vitro dissolution tests. The patent claim was held indefinite for failure to instruct PHOSITA on how the ‘local pH’ was related to ‘micro-environmental pH’ with reasonable certainty. If the patentee had provided the relevant technical literature supporting the correlation of ‘local pH’ to ‘microenvironmental pH’, it would have been possible to rebut the indefiniteness challenge. Thus, a technical term can lead to indefiniteness when the patentee uses the term in a manner not supported by the relevant technical literature and also has not acted as a lexicographer. Implications for drafting Words in a claim will be given their ordinary and accustomed meaning unless the inventor has used them differently, ie as a lexicographer. The cases examined reveal that relative terms can be appropriately used in the patent drafting so long as adequate support is provided to put the public on notice of the scope of the claims. The support can come from examples, drawings or embodiments of the invention in the specification. However, how support would be provided depends on the field of technology to which invention relates. For instance, for mechanical inventions support can come from the drawings. In Biosig v Nautilus, the term ‘spaced relationship’ was used in referring to spacing between the electrodes positioned in a cylindrical bar that a user grips with both hands on exercise apparatus with heart rate monitor. It is clear from the claim that the term ‘spaced relationship’ was a term of degree as it described the relative positions of electrodes with respect to each other. The specification and figures illustrated the ‘spaced relationship’ can be ‘neither infinitesimally small nor greater than the width of a user’s hands’ because (i) the asserted claims required detection of electrical signals at two distinct points of a user’s hand, and (ii) it was not feasible for the electrodes to be infinitesimally small such that electrodes are effectively merged into one detection point. For claim involving New Chemical Entities, the scope of the claims could be determined from the embodiments of the invention as well as based on the distinguishing tests given in the examples. At the time of patent filing, while the invention has been reduced to practice, it is difficult to capture it in words. When the patentee cannot find appropriate words to claim the invention, for it is new, the claim is likely to be held indefinite for want of suitable words. Patent law, in such situation, lets the patentee be a lexicographer. As illustrated in King v Purdue, ‘bioequivalent’ was used to mean ‘equivalent antagonistic effect’, which justified any intended or unintended variation in the meaning of the claim term necessary to support in the specification.49 The language of the patent as well as the prosecution history supported this meaning. Therefore, it is important that the meaning attributed by the lexicographer be supported by the intrinsic evidence. The lexicographer should not ascribe multiple meanings at different places in the patent. The option may be exercised when the existing words are inadequate to capture the essence of the invention. For words of degree and subjective terms, it would be desirable to provide explicit comparator sin the claim as well as in embodiments; citing a comparative example would also suffice, so that an objective enquiry can be made. In certain situations, it is inevitable to use these imprecise terms. For instance, assume the following hypothetical claims referring to the pharmaceutical composition: Claim A: A pharmaceutical composition which comprises 40–60% drug A, and 20–30% drug Y. Claim B: A pharmaceutical composition which comprises about 40–60% drug A, and about 20–30 % drug Y. It is always easier for the patentee to write a claim as in Claim A, but if another pharmaceutical composition contained drug X in the range slightly below or slightly above the stated range, such product would be excluded from the literal scope of Claim A. The patentee has no choice but to resort to the doctrine of equivalents to establish infringement, which is not an easy task. However, it is fairly likely that the court would regard the same pharmaceutical composition as infringing within the literal scope of Claim B. However, one has to keep in in mind that use of words of degree such as ‘about’ does not prevent from application of doctrine of equivalents unless that numerical range preceding the term ‘about’ already captured what would otherwise be equivalents within the literal scope of the claim. Thus, although not completely banned, judicious and thoughtful use of such terms is required in the patent drafting. When the term ‘about’ is used along with modifying open-ended language such as ‘at least’, ‘not greater than’, ‘not less than’, etc, it always creates uncertainty of claim scope due to double indefinite qualifiers. Therefore, such language used in the claims when challenged for indefiniteness may prove fatal to the validity of the claim and its use should be avoided while drafting of the patent application. A point in favour of incorporating relative terms is that when it precedes non critical limitation, the claim is likely to survive indefiniteness challenge. Table 1 provides a useful summary of how to support potentially imprecise terms. Table 1. Categories of support in the specification for definiteness Sr No Situation Support Relevant case 1 Establishing the superiority of the product on making change to the composition of the device/composition The use of relative terms in such cases can be substantiated by giving comparison of the efficacy of the product/device with one without such change Alcon v Barr50 2 Use of ‘about’ to expand the scope of the claim The extent to which the patentee intends to extend the scope should be supported by intrinsic as well extrinsic evidence Ortho-McNeil v Kali51 3 ‘About’ coupled with open-ended language Provide numerical range or statistical deviation with the help of intrinsic or extrinsic evidence Graceway v Perrigo52 4 Subjective term Objective test within the specification to measure the scope Apotex, Inc v UCB53 5 Chemical compound or structure claim Distinct structure along with distinguishing characteristic properties of the molecule claimed Smithkline Beecham v Apotex Corp54 6 Term of art Lexicography or refer to established definition while drafting King v Purdue Pharma55 Sr No Situation Support Relevant case 1 Establishing the superiority of the product on making change to the composition of the device/composition The use of relative terms in such cases can be substantiated by giving comparison of the efficacy of the product/device with one without such change Alcon v Barr50 2 Use of ‘about’ to expand the scope of the claim The extent to which the patentee intends to extend the scope should be supported by intrinsic as well extrinsic evidence Ortho-McNeil v Kali51 3 ‘About’ coupled with open-ended language Provide numerical range or statistical deviation with the help of intrinsic or extrinsic evidence Graceway v Perrigo52 4 Subjective term Objective test within the specification to measure the scope Apotex, Inc v UCB53 5 Chemical compound or structure claim Distinct structure along with distinguishing characteristic properties of the molecule claimed Smithkline Beecham v Apotex Corp54 6 Term of art Lexicography or refer to established definition while drafting King v Purdue Pharma55 Open in new tab Table 1. Categories of support in the specification for definiteness Sr No Situation Support Relevant case 1 Establishing the superiority of the product on making change to the composition of the device/composition The use of relative terms in such cases can be substantiated by giving comparison of the efficacy of the product/device with one without such change Alcon v Barr50 2 Use of ‘about’ to expand the scope of the claim The extent to which the patentee intends to extend the scope should be supported by intrinsic as well extrinsic evidence Ortho-McNeil v Kali51 3 ‘About’ coupled with open-ended language Provide numerical range or statistical deviation with the help of intrinsic or extrinsic evidence Graceway v Perrigo52 4 Subjective term Objective test within the specification to measure the scope Apotex, Inc v UCB53 5 Chemical compound or structure claim Distinct structure along with distinguishing characteristic properties of the molecule claimed Smithkline Beecham v Apotex Corp54 6 Term of art Lexicography or refer to established definition while drafting King v Purdue Pharma55 Sr No Situation Support Relevant case 1 Establishing the superiority of the product on making change to the composition of the device/composition The use of relative terms in such cases can be substantiated by giving comparison of the efficacy of the product/device with one without such change Alcon v Barr50 2 Use of ‘about’ to expand the scope of the claim The extent to which the patentee intends to extend the scope should be supported by intrinsic as well extrinsic evidence Ortho-McNeil v Kali51 3 ‘About’ coupled with open-ended language Provide numerical range or statistical deviation with the help of intrinsic or extrinsic evidence Graceway v Perrigo52 4 Subjective term Objective test within the specification to measure the scope Apotex, Inc v UCB53 5 Chemical compound or structure claim Distinct structure along with distinguishing characteristic properties of the molecule claimed Smithkline Beecham v Apotex Corp54 6 Term of art Lexicography or refer to established definition while drafting King v Purdue Pharma55 Open in new tab Conclusion Our analysis leads to the conclusion that words of degree or subjective terms are not the only terms leading to claim definiteness issues: technical terms or any other term whose meaning is not clear could lead to indefiniteness. Therefore, avoiding the use of relative terms is not the solution to avoid indefiniteness. The use of relative terms helps a patentee to claim a slightly broader scope of the invention, so long as the same is appropriately supported in the description. The courts have classified the terms as words of degree or subjective terms or terms of art to decide claim definiteness. However, these considerations are of little help while drafting a patent application. Since the standard used to assess the claim definiteness is the same irrespective of the classification of the terms—ie claims, read in light of the specification delineating the patent and the prosecution history, must inform, with reasonable certainty, those skilled in the art about the scope of the invention, there is no need to classify the words in categories as mentioned above at drafting stage. Since the case law does not provide any bright line rule regarding the definiteness of claims containing these terms, the only recourse a patentee has is to provide adequate support in the description to delineate the scope of the claim with reasonable certainty, as mandated by 35 USC section 112b. Footnotes 1 Nautilus, Inc v Biosig Instruments, Inc (2014) 134 S Ct 2120, 2129. 2 Festo Corp. v Shoketsu Kinzoku Kogyo Kabushiki Co (2002) 535 US 722, 731. 3 Tun-Jen Chiang and Lawrence B Solum, ‘The Interpretation-Construction Distinction in Patent Law’ (2013) 123 YALE LJ 530, 540. 4 Amir H Khoury, ‘The Unlimitless: On How to Remedy the Inadequacies of a Language-Based System for Patent Claims’ (2016) 24 Tex Intell Prop LJ 103, 130. 5 Stephen J Stark, ‘Key Words and Tricky Phrases: An Analysis of Patent Drafters' Attempts to Circumvent the Language of 35 U.S.C. § 112’ (1997) 5(1) J Intell Prop L 3655. 6 Peter G Dilworth, ‘About “About” and Other Imprecise Claim Terms’ (1996) 78 J Pat & Trademark Off Soc'y 423. 7 Holger Tostmann, ‘Protecting Chemistry Inventions: The Double-Edged Sword of Being an Unpredictable Art’ (2015) 6(4) ACS Med Chem Lett. 8 (2015) Civil Action No 13-1644 (RGA) (D Del). 9 In 2014, in Biosig v Nautilus (n 1), the Supreme Court introduced ‘reasonable certainty’ standard to assess the definiteness of claim. The Court abrogated the Federal Circuit’s previous inquiry into whether patent claims were ‘amenable to construction’ or ‘insolubly ambiguous’, which was introduced in 2001 in Exxon v US. The cases decided after 2014, refer to reasonable certainty standard in deciding indefiniteness. 10 (2011) 837 F Supp 2d 364 (D Del). 11 ibid 386. 12 (2016) Case No 2:15-CV-1455-WCB (ED Tex). 13 See Deere & Co v Bush Hog, LLC (2012) 703 F 3d 1349, 1359 (Fed Cir) (‘This court has repeatedly confirmed that relative terms such as “substantially” do not render patent claims so unclear as to prevent a person of skill in the art from ascertaining the scope of the patent.’); Ecolab, Inc v Envirochem, Inc (2001) 264 F 3d 1358, 1367 (Fed Cir) (‘[L]ike the term “about,” the term “substantially” is a descriptive term commonly used in patent claims’); Andrew Corp v Gabriel Elecs, Inc (1988) 847 F 2d 819, 821 (Fed Cir) (terms such as ‘close to’, ‘substantially equal’ and ‘closely approximate’ are ‘ubiquitous in patent claims’). 14 (1984) 731 F 2d 818, 826 (Fed Cir). 15 Andrew v Gabriel (n 13). 16 (2007) 482 F Supp 2d 478 (DNJ). 17 Allergan v Teva (n 12). 18 Cohesive Techs, Inc v Waters Corp (2008) 543 F 3d 1351, 1368 (Fed Cir). 19 (1991) 927 F 2d 1200, 1217–18, (Fed Cir). 20 ibid 1218. 21 ibid. 22 (2005) No CV03-1209-MO (D Or). 23 (2011) Civil No 1: CV-09-1685 (MD Pa). 24 (2008) 547 F Supp 2d 436, 43 (ED Pa). 25 (2011) Civil Action No: 2:10-cv-00937 (DNJ). 26 (2005) No C 05-01938 WHA, 3 (ND Cal). 27 (2013) Cause No 2:11-CV-530-JRG (ED Tex). 28 (1945) (2d Cir) 150 F.2d 885 (L Hand, J). 29 (1996) 81 F 3d 1554 (Fed Cir). 30 (2016) Case No 2:15-cv-1001-JRG-RSP (ED Tex). 31 Allergan v Teva (n 12). 32 (2013) 6:11-cv-441 (ED Tex). 33 (1999) 64 F Supp 2d 233 (WDNY). 34 (2016) CA No 14-121-LPS (D Del). 35 See PAR Pharms, Inc v TWI Pharms, Inc (2013) Civil No CCB-11-2466 (D Md); Re Cyclobenzaprine Hydrochloride Extended–release Capsule Patent Litig (2011) 794 F Supp 2d 517, 527 (D Del). 36 (2013) 970 F Supp 2d 1297 (S.D. Fla). 37 (2014) 994 F Supp 2d 367 SDNY. 38 Smithkline Beecham Corp v Apotex Corp (2005) 403 F 3d 1331 (Fed Cir). 39 Ortho-Mcneil Pharmaceutical v Mylan Laboratories (2004) 348 F Supp 2d 713 (NDW Va). 40 Smithkline Beecham v Apotex Corp (n 38). 41 ibid 1334–35. 42 ibid 1335–36 (‘seeding’ or ‘disappearing polymorph’ theory). 43 Re Gardner (1970) 427 F 2d 786 (CCPA). 44 Bischoff v Wethered (1869) 76 US (9 Wall) 812, 19 L Ed 829. 45 Specialty Composites v Cabot Corp (1988) 845 F 2d 981, 985 (Fed Cir). 46 Actavis v UCB (n 30). 47 (2010) 718 F Supp 2d 703. 48 (2016) Civil Action No 13-1674-RGA (D Del). 49 King Pharmaceuticals Inc (n 47). 50 Alcon v Barr (n 10). 51 Ortho-McNeil v Kali (n 16). 52 Graceway v Perrigo (n 25). 53 Apotex (n 36). 54 Smithkline Beecham v Apotex Corp (n 38). 55 King Pharmaceuticals Inc (n 47). © The Author(s) 2019. Published by Oxford University Press. All rights reserved. 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TI - Determinants of claim definiteness: myth of relative terms
JF - Journal of Intellectual Property Law & Practice
DO - 10.1093/jiplp/jpz111
DA - 2019-10-01
UR - https://www.deepdyve.com/lp/oxford-university-press/determinants-of-claim-definiteness-myth-of-relative-terms-QY0vQiqaEf
SP - 796
VL - 14
IS - 10
DP - DeepDyve
ER -