Monday, April 26, 2010

Examiner's interpretation of a claim term should not conflict with the reference

This is the third in a series of blog posts about arguing the meaning of claim terms. Previous posts are here and here.

Takeaway: The BPAI has limited the broadest reasonable interpretation doctrine by citing In re Cortright, 165 F.3d 1353, 1358 (Fed. Cir. 1999), which holds that the broadest reasonable interpretation "should not be so broad that it conflicts with the meaning given to identical terms in other patents from analogous art."

Here are a few BPAI decisions that use this doctrine to rein in the Examiner's unreasonably broad interpretation.

In Ex parte Hada, the claims on appeal were directed to an air dryer used in paper manufacturing. The limitation at issue was "heads," and the real issue was the meaning of this term.

The Examiner alleged that the "heads" were taught in the reference by structures numbered 26 and 28. The Applicant argued that the Examiner's reading was contradictory to the plain teachings of the reference. The Applicant noted that the reference used the claim term "head" to refer to a different structure (32), while the reference referred to structures 26 and 28 by the terms "inlet plenum" and "outlet duct," respectively.

The Examiner argued that "[t]he plain meaning, consistent with Appellants specification, of 'two opposing heads' include the ducts 26, 26' and ducts 28, 28' disclosed in [reference] because both form a head or inlet/outlet end duct region." The Examiner thus implicitly interpreted head as "duct located in an end region."

The Board analyzed as follows:
Kimberly-Clark’s Specification provides enlightenment as to the meaning of the term “heads”. According to the Specification, “heads” is used to describe the surfaces that close the ends of the through-air dryer roll [30]. FF 1. Sisson, the applied prior art, also utilizes the term “heads” to describe the closure of the sieve roll [21] at each end. FF 5. We find that Sisson’s heads are structurally similar to Kimberly-Clark’s described heads. FF 6. In light of the meaning given to “heads” by Sisson and its use in Kimberly-Clark’s Specification, one of ordinary skill in the art would understand the term “heads” to mean the closures at the ends of the roll.

The Board finished by stating that "the broadest reasonable interpretation should not be so broad that it conflicts with the meaning given to identical terms in other patents from analogous art," citing to In re Cortright.

In Ex parte Madhav, the claims at issue were directed to coating metal surfaces. The real issue was the meaning of the term "metal alloy." One reference disclosed chemically combined forms of metals and the other disclosed a modified metal. The Examiner took the position that the claimed "metal alloy" read on both.

The Board made several findings of fact related to the Applicant's specification and the references:
7. The Specification does not explicitly define the terms “metal alloy” or “master alloy.”
8. The Examiner did not identify an explicit use of the term “alloy” by either Hayman or Ackerman in describing the coating materials utilized in their processes. (See generally, Ans.) Both Hayman and Ackerman do use the term “alloy” when describing the components to which the coating materials are applied.
The Board then relied on these findings to hold that: 
[t]he Examiner’s interpretation runs counter to the use of these terms in the references (see FF 2, 3, and 8 (using the term “alloy” to describe the substrate, but not the coating material)) as well as in the related prior art (see FF 9 (distinguishing “chemically combined” from “alloy” metals)).
The opinion's Conclusions of Law section quoted from, though did not cite to, the above referenced sentence in In re Cortright.

My two cents: I don't suggest using this sort of argument every time the reference uses a different term than a claim. After all, "the elements must be arranged as required by the claim, but this is not an ipsissimis verbis test, i.e., identity of terminology is not required." (In re Bond, 910 F.2d 831, 832 (Fed. Cir. 1990)).

Save this argument for those cases where you have evidence that the Examiner's interpretation is inconsistent with how a POSITA understands the term. This evidence can be in your spec, in the cited references, or even (as in Hada) in "related references."


  1. These both appear, on their faces, and insofar as quoted to be bad decisions. If "head" refers to the structure of a duct, perhaps an outlet duct, then the term reads thereon. People in various references throughout the art can use a variety of phrases to refer to the same structure. You can call a plastic clip a "plastic attachment feature" or a plastic clip, you're still referring to the same thing.

    I cannot be bothered to review these cases entirely, but I would urge caution before relying on a distinction without a difference as appears to have been done by the board in these cases. Regardless of whether or not you may win at the board. I can assure you that you're asking for trouble when the DC gets around to your case.

  2. >If "head" refers to the structure of a duct,
    >perhaps an outlet duct,
    >then the term reads thereon.

    Precisely: "if". It's this question of *whether* head means duct that was at issue.

    The Examiner in Hada said nothing more: my interpretation of "head" is "duct". The Examiner in Hada offered no reasoning or evidence as to why that interpration is correct.

    >People in various references throughout
    >the art can use a variety of phrases to
    >refer to the same structure.'

    Agreed. The Board reviewed the term "head" as used in the reference and as used in the spec, and decided that "head" did not mean "duct".

    My post didn't say "argue that head doesn't mean duct because they're two different words". My post said an argument may be appropriate when the Examiner's interpretation *conflicts with the reference*.

    Perhaps I'll revise my post to make this point clearer.

    >I can assure you that you're asking for
    >trouble when the DC gets around to your

    The District court will review evidence (intrinsic and extrinsic) about the meaning of claim terms, and decide based on that evidence.

    In some fact situations, the meaning of "word1" may encompass "word2", even though different words are used. In others, this may not be the case.