Claim Construction, Patent Litigation

There has been a lot of discussion in the patent world recently about how to improve patent quality.  Much of this discussion has been motivated or at least strongly influenced by the surge in patent litigation brought by “patent trolls.”  As we discussed last month, Congress is attempting to reduce the leverage that patent trolls enjoy in patent litigation via the SHIELD Act.

Improving the degree of predictability and certainty in patent litigation is another way to curb perceived abuses of the patent litigation system, including by patent trolls.  This month we will address one way in which this can be done: by eliminating non-limiting “statements of intended use” in patent claims.

The Problem With Statements of Intended Use

The claims of the patent define the scope of what is protected.  A patent claim is infringed if each limitation of the claim is practiced, either literally or under the doctrine of equivalents.  However, one vexing problem that occurs in many lawsuits concerns the issue of whether certain language in patent claims constitutes an actual limitation or instead is merely a “statement of intended use”.  A true statement of intended use, as the name suggests, describes a manner in which a claimed invention may be used, but does not limit the claim and need not be practiced in order to find infringement.  However, in some cases, language that appears to be a mere statement of intended use may be deemed limiting by the courts.  This possibility produces uncertainty in patent litigation, with parties disagreeing over whether particular language is actually limiting.  Here is an example of a claim that includes a statement of intended use from a 1998 Federal Circuit case:

21. A biopsy needle for use with a tissue sampling device having a housing with a forward end, a first slide mounted for longitudinal motion within said housing, and a second slide mounted for longitudinal motion within said housing, said biopsy needle comprising:

a hollow first needle having proximal and distal ends;

a second needle extending through said hollow first needle and freely slidable therewithin, said second needle having proximal and distal ends;

a first head mounted to said proximal end of said hollow first needle, said first head including first flange means associated therewith for coupling said hollow first needle to said first slide for longitudinal motion both toward and away from said forward end of said housing; and

a second head mounted to said proximal end of said second needle, said second head including second flange means associated therewith for coupling said second needle to said second slide for longitudinal motion both toward and away from said forward end of said housing.

C.R. Bard, Inc. v. M3 Systems, Inc. 157 F.3d 1340, 1348-49 (Fed. Cir. 1998).  The word “for” in a claim is often a signal that the following language may merely be a statement of intended use.  The Bard claim states that it is for a biopsy needle.  However, the underlined limitations concern a housing that is used with the biopsy needle, not the needle itself.  If the housing features are limitations, the claim can only be directly infringed by someone who supplies the needle and the housing.  If the housing features are not limitations, a needle supplier can be held liable for infringement without supplying a housing.  Also, if the housing features are not limitations, they cannot be considered in distinguishing the prior art.

Statements of intended use typically, but not always, arise in claim preambles (the first paragraph of the claim before the word “comprising”).  Statements of intended use may be deemed to be actual claim limitations under certain circumstances.  For example, if the intended use was relied upon to distinguish the prior art during prosecution of the patent, it may be deemed limiting.  Also, if the other portions of the claim refer back to a statement of intended use in the preamble, the statement may be deemed limiting.

The law governing the treatment of statements of intended use produces a great deal of uncertainty during patent litigation as to whether and how such statements may limit claim scope.  With respect to the Bard biopsy needle claim, the Court ultimately held that the housing limitations were not limiting, but that they “provide[d] reference points . . . that aid in defining the needles.”  Id. at 1349.

In May of last year, the Board of Patent Appeals and Interferences (now the Patent Trial and Appeals Board) reviewed a series of appeals in which statements of intended use were included in the body of patent claims and concluded that they were not limiting.  Here is an example from one of the appeals:

1. A networked media station comprising:

at least one network interface; and

at least one multimedia interface;

wherein the networked media station is configurable to receive multimedia data pushed from a multimedia server via the at least one network interface and output the multimedia data to an entertainment de-vice attached to the at least one multimedia interface.

Ex parte Kearney, 2012 Pat. App. LEXIS 2675 at *1 (BPAI 2012).  The Board held that the underlined and bolded language “merely expresses an intended use of the recited ‘networked media station’.”  Id. at *5.  As a result, the Board refused to consider whether the prior art media stations actually received multimedia data in the described way, holding that “the disputed limitation of ‘multimedia data pushed from a multimedia server’ is not positively recited as actually occurring . . . .”  Id.

The problem with this type of claim language is that in many instances, patent examiners do not force applicants to commit to whether features in statements of intended use are meant to limit the claim unless the features are required to distinguish a particular piece of prior art.  If the issue is not addressed during prosecution, once the patent issues the patent holder is free to argue that the language is or is not limiting depending on its particular lawsuit targets.  In the Kearney case, had the patent issued with the foregoing claim, the patent holder would have been able to assert that those who merely supply network media stations directly infringe the claim as long as users use the media station with a multimedia server as claimed.  At the same time, the patent holder would be able to distinguish prior art that does not disclose the claimed relationship between the network media station and multimedia server.  We have seen this sort of claim construction dynamic play out in several patent troll cases to the advantage of the troll and the disadvantage of the accused infringers.  Many of these cases involved multi-component computer or network systems in which the alleged novelty lies in the interaction between the various components, not in any one component itself.  The trolls gain the benefit of the intended use in distinguishing the prior art while still being able to sue companies who supply only one component in the claim for direct infringement.

Forcing Patent Applicants to Commit During Prosecution

If a patent applicant does not intend to limit its claims to an intended use, there would seem to be few benefits—and significant disadvantages—in allowing it to include statements of intended use in its claims.  If the Bard claim was intended to cover only a biopsy needle, the applicant could have readily described the needle as a stand-alone object without introducing the housing.  If the Kearney claim was intended to cover a system comprising a networked media station and multimedia server, it could have positively recited both components.

One way to minimize the ambiguity and uncertainty that statements of intended use produce is to have patent examiners require applicants to commit to the intended scope of their claims during prosecution, even if the prior art does not otherwise require the issue to be raised.  If the applicant wishes to limit the claims to an intended use, the claims should positively recite those features and make clear that they are limiting.  Otherwise, the statements should be removed from the claims.  There is little justification for allowing patents to issue with this type of ambiguous claim scope.   The resulting improvement in the clarity of patent claims would reduce the ambiguity and uncertainty that many patent trolls exploit to their advantage.

Some patent holders may contend that certain inventions are best described in terms of the components with which they are “configured to” or “adapted to” interact and that the language in cases like Kearney is neither a mere statement of intended use or a positive recitation of an entire system (i.e., the network media station and the multimedia server).  The Bard court seemed to take this sort of middle of the road approach.  The Federal Circuit has noted that “In common parlance, the phrase ‘adapted to’ is frequently used to mean ‘made to,’ ‘designed to,’ or ‘configured to,’ but it can also be used in a broader sense to mean ‘capable of’ or ‘suitable for.’”  Aspex Eyewear, Inc. v. Marchon Eyewear, Inc., 672 F.3d 1335, 1349 (Fed. Cir. 2012).  In many cases, patents that use this sort of language do not clearly indicate which meaning is intended.  In such cases as well, it would be beneficial to require the applicant to commit to one position or another because it may significantly impact the scope of the applicant’s claims and the manner in which they relate to potential accused products and the prior art.

It would be inefficient to force patent examiners to require applicants to define or explain the meaning of every term in their claims, especially when their meaning is not called into question by the prior art.  However, statements of intended use and language such as “configured to” or “adapted to” occur frequently and often produce unnecessary ambiguity.  Thus, this is one area where it would be helpful and not necessarily too burdensome to flesh out the applicant’s intended claim constructions during prosecution.