The interpretation-construction distinction in patent law.

• Author: Chiang, Tun-Jen
• Position: IV. Why Disputes Are over Construction through Conclusion, with footnotes, p. 572-614

4. WHY DISPUTES ARE OVER CONSTRUCTION

   1. The Conventional Framing: Dictionary Versus Specification as Guides to Linguistic Meaning

      In the conventional framing, the Federal Circuit is divided into two camps. (152) One camp, the "dictionary-first" camp, supposedly sees the dictionary as being the best guide to linguistic meaning:

      Dictionaries, encyclopedias and treatises, publicly available at the time the patent is issued, are objective resources that serve as reliable sources of information on the established meanings that would have been attributed to the terms of the claims by those of skill in the art. Such references are unbiased reflections of common understanding ... not colored by the motives of the parties, and not inspired by litigation. (153) The opposing camp, commonly called the "specification-first" camp, supposedly opposes the dictionary-first camp by arguing that the patent specification provides a better guide to linguistic meaning:

      The best source for understanding a technical term is the specification from which it arose, informed, as needed, by the prosecution history. The evolution of restrictions in the claims, in the course of examination in the PTO, reveals how those closest to the patenting process-the inventor and the patent examiner-viewed the subject matter. (154) What happens frequently in cases is that one camp of judges will cite the dictionary to support a broad construction of the claim, while another camp of judges will cite the specification for a narrow construction. In Phillips, for example, the majority opinion invokes a dictionary definition to say that "baffle" means a steel support capable of "obstruct[ing] the flow of something" generally, (155) while the dissent cites the specification to say that "baffles" in the particular patent must be angled and capable of deflecting bullets. (156) Rhetorically, both sides appear to be pursuing the linguistic meaning, just using different tools.

   2. The Real Dispute: Linguistic Meaning Versus the "True" Invention

      The core payoff of applying the interpretation-construction distinction in patent law is to show that the conventional framing is fundamentally misconceived. The conflict does not occur because the dictionary-first camp and the specification-first camp are both pursuing the linguistic meaning but coming to different results. Rather, the uncertainty in claim analysis arises because some judges adopt a textualist theory of construction that pursues the linguistic meaning of claim text while others adopt a theory of construction that pursues the true invention. It is this age-old conflict between textualism and anti-textualism--a quintessentially normative conflict-that causes claim uncertainty. Below, we elaborate on the mechanism by which this conflict arises.

      1. Doctrine Treats the Patentee's Invention as Equivalent to the Linguistic Meaning of Claim Text

         Initially, we think it utterly uncontroversial to say that judges routinely seek to construe claims to cover the patentee's invention. Indeed it is considered axiomatic that they do so. Courts treat "the understanding of claim text by a person of skill in the art" and "the patentee's invention" as if they were interchangeable and equivalent concepts. In United States v. Adams, the Supreme Court says "it is fundamental that claims are to be construed in the light of the specifications and both are to be read with a view to ascertaining the invention." (157) In Phillips v. AWH Corp., the Federal Circuit holds that the question for claim construction is "how a person of ordinary skill in the art understands a claim term." (158) The courts perceive absolutely no difference between these two formulations. Indeed, often the same case recites both formulations in one breath. (159)

      2. The Patentee's Invention Is Not the Linguistic Meaning of Claim Text

         What these courts do not appreciate is that the patentee's invention is not the linguistic meaning of claim text. The "invention" is the new, useful, and non-obvious idea that the patentee discloses in the patent specification. The linguistic meaning of claim text is how a person of ordinary skill in the art would understand the language of the claim text. The relevant relationship between the two is that section 112 of the patent statute says the patentee is supposed to write claim text that covers his actual invention. (160) The fact that the patentee has a statutory duty to write claims that cover the invention, however, does not mean that patentees inherently comply. It is absurd to equate the existence of a duty with compliance at a conceptual level. If a tax evader claims an income of "zero" on his tax return when his actual income was one million dollars, no one would argue that courts should therefore read "zero" to really mean "one million."

      3. Examples of Conflation

         Examples will prove our proposition that courts incorrectly conflate the two concepts into a single doctrine, which then allows individual judges to invoke different theories of construction while purporting to apply a shared concept of "meaning." Our prior discussion of Phillips already provided one example. (161) In Phillips, beneath a veneer of agreement regarding claim construction doctrine, (162) there is in fact no agreement at all: the majority is looking for the linguistic meaning of "baffle," while the dissent is looking for the true invention.

         A second example--with the arguments the same but the results reversed--is Retractable Technologies, Inc. v. Becton, Dickinson & Co. (163) The facts of the case involve a patent on a type of syringe with a "body." In the patent specification, all the examples given were of one-piece syringes. The question was whether the claim term "body" covered a competitor's two-piece syringe.

         The majority opinion began by looking at the ordinary meaning of "body," and conceded that the ordinary meaning alone could cover syringes with multiple pieces. However, it then held:

         In this case, while the claims leave open the possibility that the recited "body" may encompass a syringe body composed of more than one piece, the specifications tell us otherwise. They expressly recite that "the invention" has a body constructed as a single structure, expressly distinguish the invention from the prior art based on this feature, and only disclose embodiments that are expressly limited to having a body that is a single piece. Thus, a construction of "body" that limits the term to a one-piece body is required to tether the claims to what the specifications indicate the inventor actually invented. (164) This quote clearly demonstrates that the Retractable Technologies majority is construing the scope of the claim based on its conception of what the patentee invented. This is in contrast to the approach of the Retractable Technologies dissent, which focuses its analysis on the linguistic meaning of "body." The dissent begins by noting that "[t]he ordinary and customary meaning of 'body' does not inherently contain a one-piece structural limitation." (165) It then argues that the fact that the patentee used the words "one-piece body" in the specification actually creates a linguistic inference that "body" is not limited to a single piece object: if the patentee had thought that "body" was a label for an object that inherently had only a single piece, then the phrase "one-piece body" would be redundant. (166) Once again, we have two camps that are speaking past each other because they are looking for different things.

         A final example that illustrates why this divide causes so much uncertainty is Marine Polymer Technologies, Inc. v. Hemcon, Inc., (167) where the en banc Federal Circuit divided exactly 5-5- In Marine Polymer, the patentee invented a process for creating a type of polymer, known as poly-[beta]-1[right arrow]4-Nacetylglucosamine (p-GlcNAc), which is useful in medical applications. (168) In particular, the patentee developed what he called "biocompatible" p-GlcNAc, which everyone agreed was a reference to the compound's degree of biological reactivity (lower reactivity was better). (169) The precise question at issue was whether the word "biocompatible" specifically denoted zero reactivity.

         In the first opinion, authored by Judge Lourie, one half of the court argued that "biocompatible" meant that a compound must have zero detectable reactivity. (170) Judge Lourie based his decision exclusively on a passage from the specification that stated: "[I]t is demonstrated that the p-GlcNAc of the invention exhibits no detectable biological reactivity." (171)

         In the second opinion, authored by Judge Dyk, the other half of the court argued that "biocompatible" meant only that a compound exhibits low reactivity and did not necessarily have to exhibit zero detectable reactivity. (172) Judge Dyk based his decision on the fact that the patentee had written two sets of claims (173): In one set of claims, the patentee had claimed all "biocompatible" p-GlcNAc compounds generically; (174) while in the other set of claims he had specifically claimed a "biocompatible poly-[beta]-1[right arrow]4-N-acetylglucosamine ... which has an elution test score of 1" (the elution test is a test of reactivity, with a score of zero denoting no detectable reactivity). (175) If the word "biocompatible" itself denoted a compound that had zero detectable reactivity, then a claim to "biocompatible p-GlcNAc having an elution test score of 1" (denoting low detectable reactivity) would be nonsensical.

         Once we conceptually distinguish between the linguistic meaning and the patentee's invention, it becomes clear again that the court is really disagreeing over the proper theory of construction. Judge Lourie's opinion is focusing on what the patentee invented. Judge Dyk's opinion is focusing on what the linguistic rules of English tell us about the linguistic meaning of the word "biocompatible." There is in fact no contradiction between saying that the word...