THE DEATH OF THE GENUS CLAIM.

• Author: Karshtedt, Dmitry

TABLE OF CONTENTS I. INTRODUCTION 3 II. GENUS CLAIMING: THE TRADITIONAL VIEW 5 A. Understanding Patent Claims 5 1. Claim Scope and the Disclosure Function of Patents 6 2. Enablement and the Sufficiency of Disclosure 7 3. Enablement's Commensurability Requirement 10 B. The Traditional Role of Genus Claims in Chemistry 13 C. Portents of Change 17 1. The Written Description Requirement 17 2. The Rise and Nature of Biotechnological Inventions 20 III. THE MODERN ERA: GENUS CLAIMS FAIL IN COURT 22 A. Rejecting Claims on Enablement Grounds 23 1. The Antecedents of Doctrinal Drift 23 2. The New Law of Genus Claim Nonenablement 27 B. Written Description and the Possession of Genus Claims 35 1. Lilly and Written Description as Enablement Plus 36 2. Entrenchment and Growth as a Weapon Against Genus Claims 40 a. The Ariad Case 40 b. Further Impact on Genus Claims 42 C. Claims Surviving [section] 112(a) Challenges 46 1. Interferences 47 2. Small Genuses and Genuses Known Prior to the Invention 49 3. Other Cases 50 IV. SHOULD WE SAVE GENUS CLAIMS? 54 A. A Troubling Shift in Precedent 54 1. What Does the PHOSITA Know? 54 2. "Making and Using... the Full Scope of the Invention" 56 3. Recognizing When We Need to Understand What Works... and When We Don't 57 a. Improper Generalization 59 b. Gun Jumping and Late Claiming 61 4. The New Full-Scope Requirement 62 B. Can Pharmaceutical Patent Owners Survive Without Genus Claims? 63 C. Implications for Other Industries 70 V. CONCLUSION 72 I. INTRODUCTION

The most fundamental rule of patent law is that what the patentee owns is defined not by what she actually built or described, but by the patent claim--the legal definition of the invention drafted by her patent lawyer. Lawyers draft those claims as broadly as the law appears to allow. In particular, lawyers are careful not to limit the claim to a particular thing or "species," even though that's normally what the patentee actually built or conceived. Instead, patent lawyers lead with a "genus claim"--a broad claim that covers a group of structurally related products that incorporate the basic advance of the patented invention. (1) They do this to make sure that no one can copy their basic idea by making a small change to it to avoid infringing the patent.

Nowhere is this more true than in the chemical arts. (2) Pharmaceutical, biotechnology, and chemical companies rely more heavily on the patent system than do other industries. (3) Some scholars have concluded that the system works well in those industries but not others. (4) And those industries make heavy use of genus claims. A chemical patent, for instance, might include one or more claims to a particular compound--a species--but almost invariably it starts with a claim to a group of chemicals--the genus. It bears emphasizing that these genus claims are thought important to prevent competitors from capturing the benefit of an invention while avoiding infringement by making a minor change to one aspect of it. The U.S. Patent and Trademark Office ("USPTO") grants broad genus claims as a matter of course in the chemical industries. (5) And those industries regularly attempt to enforce such claims in court. (6)

When they do, however, something surprising happens. As we show in this Article, courts almost invariably hold genus claims invalid under 35 U.S.C. [section] 112(a) for failure to enable or describe the full scope of the claimed invention. In the last thirty years, the U.S. Court of Appeals for the Federal Circuit (the court with exclusive jurisdiction over patent appeals) has struck down claim after claim on the theory that whatever the patentee has done to justify a broad claim to a group of chemicals, it isn't enough. It regularly reverses district courts that have found adequate support for the genus claim. (7) Not once but three times has the Federal Circuit thrown out a jury verdict of over a billion dollars because it concluded the genus claims at issue were invalid. (8) In fact, we find only a small minority of Federal Circuit decisions that have upheld a genus claim in the chemical industry in the past thirty years, and each of those has some idiosyncrasy that explains why it bucks the trend. (9) That trend, as reflected in dozens of cases, is unmistakable: biotechnology, chemical, and pharmaceutical genus claims lose in court.

It's unclear whether patent lawyers and scholars have discovered this shift in the jurisprudence. Patent lawyers continue to draft genus claims, the USPTO grants them, and patent owners attempt to enforce them in court. Lawyers and scholars sometimes lament individual decisions they disagree with. But the whole system seems to proceed merrily along on the assumption that the role of genus claims in supporting these industries is secure. It isn't.

We argue that the death of genus claims is the result of some subtle but important doctrinal shifts, and that those changes reflect a misunderstanding of the purposes that patent law is supposed to serve. The Federal Circuit has abandoned a practical focus on whether others could make and use the claimed invention, instead favoring a fruitless search for the exact boundaries of that invention. This "full-scope possession" theory invalidates a genus claim unless the patentee can show exactly which species within the genus will work as intended--an impossible task for a genus of any nontrivial size. (10) Given the importance of patents to the biotechnology, chemical, and pharmaceutical industries, and the importance of genus claims to those patents, we find the death of genus claims in modern courts troubling. If the doctrine continues down this path, it may threaten innovation in an important sector of the economy.

We think the law should go back to the way it was: Genus claims should survive as long as they enable other researchers to make effective use of the teachings of the patent to make and use chemicals within the genus without too much experimentation. (11) As a doctrinal matter, the validity of a claim should not depend on whether others can identify and test all of the species, and as a matter of policy, genus claims are important to innovation in these industries.

But the importance of our discovery isn't limited to getting patent policy right. The death of genus claims is also an important lesson in how the law on the ground differs from the law on the books. The fact that the industry proceeds apace--investing in innovation, obtaining and enforcing patents, despite this surprising turn in the case law--suggests that we may know less than we think we do about whether and how the patent system supports chemical innovation.

In Part II, we introduce the role of genus claims in chemical, pharmaceutical, and biotechnology patents and outline the traditional applications of [section] 112(a)'s requirements of enablement and written description to these claims. In Part III, we discuss the validity of genus claims, documenting the striking trend to invalidate those claims in the past thirty years and the subtle doctrinal shifts that led to it. Finally, in Part IV, we further examine this trend and discuss its implications for innovation in those industries--and what it says about the importance of patent doctrine more generally.

2. GENUS CLAIMING: THE TRADITIONAL VIEW

   1. Understanding Patent Claims

      Claims are central to every aspect of patent law. (12) Claims are the numbered sentences at the end of the patent document that define the "technological territory" that the patentee claims is his or hers to control, (13) and thus set the scope of the exclusory right conferred by the patent. (14) The kinds of patent claims one encounters track the language of 35 U.S.C. [section] 101, which sets forth "any new and useful process, machine, manufacture, or composition of matter" as patentable subject matter. (15) At a high level, claims can refer to a structure, such as a chair or a chemical compound, or an activity, such as a process for manufacturing the table or a method of treating an illness with the compound. In the chemical and biochemical sciences, genus claims capture a group of related molecular structures. (16) While chemical genus claims are often composition (i.e., structure) claims, many claims we will encounter in this Article are actually method claims directed to an effective treatment of some condition or to other uses of the molecules belonging to a chemical genus. (17)

      1. Claim Scope and the Disclosure Function of Patents

         The permissible scope of patent claims, and the exclusive rights they confer, are closely tied to the amount of information that the patentee discloses in the patent. Put simply, the patentee must give more (information about the invention through disclosure) to get more (claim scope). (18) This give and take lies at the heart of the U.S. patent system, which is essentially a bargain or quid pro quo between the patentee and society. (19) The patentee gets the limited period of exclusivity conferred by the patent, as set forth in the claims, so that they might recoup their investment in invention. In exchange, society gets two things: (1) use of the invention once the patent term expires, (20) and (2) the disclosure, which furnishes technical information about the invention (i.e., how to make and use it) as soon as the patent document publishes. (21) The disclosure "add[s] to the sum of useful knowledge" (22) and becomes a part of the technical literature. (23) Patent theory posits that the disclosure will stimulate other researchers to improve upon the invention, design around it, and make wholly new inventions--all during the patent term--and also to use the invention as claimed after the patent's expiration. (24) Indeed, an oft-touted justification for the patent system is that society will get some benefit from the invention's disclosure. (25)

      2. Enablement and the Sufficiency of Disclosure

         The bargain inherent to patent law only works if the patent's...