The failure of public notice in patent prosecution.

• Author: Risch, Michael

TABLE OF CONTENTS I. INTRODUCTION II. THE WHEN AND HOW OF PATENT INTERPRETATION A. Patent Prosecution and the Broadest Reasonable Construction Rule B. Litigation and the PHOSITA Rule C. Post-Grant Review III. THREE METHODS OF ENHANCING PUBLIC NOTICE IN CLAIM CONSTRUCTION A. Iterative Improvements B. Ex Ante Incentives for More Precise Claiming C. Definition of the Outer Limits of Claims IV. THE BROADEST REASONABLE CONSTRUCTION RULE: THE FAILURE OF PUBLIC NOTICE IN PATENT PROSECUTION A. Effects of the Rule on Iterative Improvements B. Effects on Ex Ante Incentives for More Precise Claiming C. Effects on the Definition of the Outer Limits of Claims V. CHANGING THE INTERPRETIVE RULE: THE PHOSITA RULE SHOULD BE USED IN PROSECUTION A. Effects of the New Rule on the Three Methods of Enhancing Public Notice in Claim Construction B. Elimination of the Harm Caused by Conflicting Rules C. The Broadest Reasonable Construction Rule Should Not Be Used in Litigation D. The New Rule Will Not Increase Costs E. Application of the New Rule VI. IMPROVING PUBLIC NOTICE WITHOUT USING THE BROADEST REASONABLE CONSTRUCTION RULE A. Enhancing the Process of Iterative Improvements: Examiners Should Require Disclaimers and Definitions but Not Claim Charts B. Increasing Ex Ante Incentives to Draft Precise Claims: Requiring Improved Written Specifications C. Improving the Definition of the Outer Limits of Claims: Relaxing the Obviousness Standard VII. CONCLUSION I. INTRODUCTION

Inventions are often difficult to describe in words, (1) and patents often contain technical information intertwined with legal meaning, (2) making patent claims more difficult to interpret than other legal documents. Despite complex interpretive rules, patent law has failed to accomplish one of its essential missions: allowing interested parties to understand a patent's scope in a consistent and predictable manner. (3) This Article argues for the abandonment of the "broadest reasonable construction" rule for interpreting claims in pending patent applications in order to enhance certainty in claim construction for those who rely on patents. Instead, pending applications should be construed using the same rule used in litigation, while patent examiners can use other methods to increase the clarity of claim meaning.

Patents are currently interpreted using different rules at different stages in the legal process. During the patent application or "prosecution" stage, the United States Patent and Trademark Office ("USPTO") examiner, who determines whether a patent should issue, gives the proposed patent claims their "broadest reasonable construction." In litigation, however, courts interpret issued claims the way a person with ordinary skill in the invention's subject matter--the patent's "art"--would interpret such claims.

Neither patent applicants nor patent examiners--two of the parties with the most appropriate means to clarify patent claims--have an incentive to create certainty in claim meaning. Patent applicants have an incentive to keep issued patent claims vague because vagueness allows for ex post gaming. Patent examiners have an incentive to issue valid patents; since the question for examiners is whether the claims are valid, they have no incentive to clarify vague patents if the claims otherwise appear valid. They understand that, if the patent claims are litigated, courts will attempt to resolve any ambiguity. Moreover, examiners know they will not be called upon to testify about their interpretation of the patent's claims.

The broadest reasonable construction rule is supposed to compensate for the lack of other incentives to produce precise patent claims. (4) In theory, the rule is supposed to create incentives for providing public notice in three ways: (1) by creating an iterative process that clarifies claims through amendments to the claims and the corresponding generation of a public record, (2) by encouraging more precise claiming by applicants in their initial application, and (3) by setting an outer boundary on the meaning of patent claims during prosecution to minimize the likelihood that potential infringers will be unfairly ensnared by a new and broader interpretation in litigation. (5) In this Article, these ways of creating clarity will be called the three "methods" of enhancing public notice.

While the broadest reasonable construction rule sometimes works as designed, it can fail in both theory and practice: (6) vague claims may not be rejected during prosecution; applicants may not have sufficient incentives to write clear claims; and the USPTO's interpretation of claims may not provide an outer boundary because courts often interpret claims more broadly than the USPTO. Indeed, the broadest reasonable construction rule often imposes costs without corresponding benefits. It harms potential competitors by leaving uncertain what inventions may infringe vague patents until it is too late and the competitor is sued for patent infringement. Even patentees may be harmed by the rule if it allows courts to interpret vague patents in a way that conflicts with the patentee's original understanding of the patent. (7)

More certainty could be achieved by having patent examiners interpret patent claims using the same rule that courts use during litigation: as a person having ordinary skill in the art ("PHOSITA") would interpret them. This approach is referred to in this Article as the "PHOSITA rule." The cost of this change would be minimal; examiners could easily read patent claims in context but are currently barred from doing so by the broadest reasonable construction rule.

Furthermore, the patent prosecution and litigation processes can be adjusted to fill any void created by the abandonment of the broadest reasonable construction rule. In particular, this Article argues for the following changes: First, patent examiners should more vigilantly reject claims that are not supported by the patent's specifications. Second, examiners should require the patentee provide disclaimers or definitions to clarify vague claims. Third, examiners should have more leeway to reject obvious claims in order to limit the outer bounds of patent claims. (8)

Part II of this Article outlines claim interpretation. (9) Part III describes the history and goals of public notice in claim interpretation and describes this Article's three-method theoretical framework for increasing claim clarity and, thus, public notice. Part IV explains why the broadest reasonable construction rule fails to promote the three methods of increasing clarity and public notice. Part V proposes abandoning the broadest reasonable construction rule in favor of the PHOSITA rule because the PHOSITA rule better fosters the three methods of enhancing public notice. Part VI proposes three supplemental approaches that would further the goals embodied in the three methods of enhancing public notice.

2. THE WHEN AND HOW OF PATENT INTERPRETATION

   This Part discusses three situations in which patents are formally interpreted: prosecution, litigation, and post-grant review. Each of these situations will also affect the informal interpretation of patents, such as is done by potential licensees. As discussed below, the primary policy goal of the interpretive rules used in these situations is the creation of clear claims.

   1. Patent Prosecution and the Broadest Reasonable Construction Rule

      A valid patent application must contain several different, statutorily defined elements. First, the patent application must describe the nature of the claimed invention and enable a PHOSITA to recreate and use the invention. (10) This description is called the "specification." 11 Following the specification there must be a list of "claims" to the invention "particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention." (12)

      During prosecution, a patent examiner (13) determines whether the application meets the criteria for patentability. (14) In order to do so, the examiner must discern what the proposed claims mean. The examiner determines a particular claim's meaning by giving the claim its "broadest reasonable construction in light of the specification." (15)

      The examiner uses the broadest reasonable construction of the claims for several purposes during prosecution. The examiner uses this construction to determine what is considered "prior art," the preexisting information that relates to the proposed patent claims. (16) This construction also affects the direction and scope of the examiner's search for prior art. Although prior knowledge or use of an invention can be prior art, patent examiners only conduct prior art searches for printed materials. (17) Patent applicants also assist with the prior art search. However, they are only required to submit printed information they know about; they need not conduct an independent search for prior art. (18)

      After completing the prior art search, the examiner compares the proposed claims to any located prior art. If any claims are not novel or are obvious in light of the prior art, (19) the examiner sends a notice of rejection of those claims. To overcome such a rejection, the applicant may amend the patent application by clarifying or narrowing the claims at issue. (20) To "narrow" a claim means to add some new claim element (or "limitation") not present in the prior art. The applicant may also explain why the prior art is not the same as the proposed claim. The record of communications between the examiner and the applicant is called the "prosecution history" and is publicly available. (21)

      If the examiner issues a final rejection and the applicant chooses not to amend the patent application or cannot convince the examiner to allow the claims, the applicant may appeal to the Board of Patent Appeals and Interferences ("BPAI"). If the patentee loses his appeal before the BPAI, he may appeal the BPAI's decision to the Federal...