Board agrees with Applicant that "a common binder polymer for the core and the shell" means identical and not merely sharing some properties

Takeaway: In a claim to toner ink for printers, the Applicant went to appeal on the issue of the meaning of
"a common binder polymer for the core and the shell." According to the Examiner, the asserted combination met this element because one reference taught styrene for the core and the other reference taught styrene for the shell. Thus, the core and shell had styrene in common. According to the Applicant, identical polymers were required, and the references did not disclose identical polymers. Instead the references taught different concentrations of styrene in the core and the shell, resulting in a different glass transition temperature. The Board found that the Examiner's interpretation was unreasonable in view of the specification and reversed the rejection. (Ex parte Massa, PTAB 2013.)

Details:

Ex parte Massa
Appeal 2012009081; Appl No. 11/870,651; Tech. Center 1700
Decided  Sep. 25, 2013

The application on appeal was directed to toners for printer ink. A representative application on appeal read:

     1. A core-shell polymer particle comprising
a common binder polymer for the core and the shell
wherein the core has a porosity and
the shell is non-porous and
the particle has a porosity of from 10 to 70 percent.

During prosecution, this claim was rejected as obvious over a combination of two references. The Examiner relied on the primary reference for the core porosity and particle porosity elements, and the secondary reference for the non-porous shell. The Examiner relied on the combination for the "common binder polymer" element, since the primary reference dislcosed that sytrene is a suitable monomer for the core while the secondary reference disclosed that sytrene is suitable for the shell. The combination taught that the core and the shell have styrene in common, and thus taught "a common binder polymer for the core and shell."

The Applicant appealed and argued that the Examiner's interpreation of "a common binder polymer for the core and the shell" was unreasonable. The combination taught core and shell binder polymers having a monomer in common, but differering in the concentration of this monomer so as to produce a difference in glass transition temperature for core and shell. In contrast, the claim required "core and shell polymers being the same, i.e., common." As evidence that "common" meant "same," the Applicant referenced a sentence in the specification stating that "the porous particles of the present invention have the same polymer for the core and shell."

The Examiner maintained his position in the Answer. Nothing the Applicant's reliance on the specification, the Examiner asserted that a POSITA "would not conclude that appellant's use of 'the same' in a sole instance in the specification mandates replacement for 'a common' throughout  the specification." The Examiner then explained that, rather than being synonyms, the words "common" and "same" were instead genus/species: 

     The term "common" [in the term at issue] represents a large range of possibilities, similar to a genus.  For example, a core comprising a mixture of binder polymers A and B would have a common binder polymer with a shell comprising a mixture of binder polymers B and C; wherein the binder polymer C would read on the claimed "a common binder polymer for the core and the shell."
     On the other hand, the term "same" as recited in the specification represents a limited number of options.  Turning to the example above, a core comprising a mixture of binder polymers A and B, would not be "the same" as a shell comprising a mixture of binder polymers B and C,  because of the presence of A and C in the core and shell, respectively. (However, the use of comprising in the preamble opens up the claim to allow for the core and shell to read on "the same").  Similar to the genus/ species relationship in which the species in the written description cannot limit the claimed genus, the use of the term "the same" in the specification cannot be employed to limit the claimed term "a common."
(Emphasis added.)

The Board found the Examiner's interpretation to be unreasonable as applied to the facts of the case.

     [W]hen the claim language is read in light of the Specification by one of ordinary skill in the art as it must be, it defines a binder polymer for the core and the shell that is the same, or identical, polymer composition. Appellants' Specification describes "the same polymer for the core and shell" (page 6, lines 2-3).
     Accordingly, while the Examiner sets forth a rationale for how, in a different context, common polymers may not be identical, we concur with Appellants that such an interpretation is not reasonable in the context of Appellants' Specification and intent.
(Emphasis added.)

The Board then reversed the obviousness rejection as being based on a flawed claim interpretation.

My two cents: I can't decide how I feel about this one.I thought the Examiner's genus/species analogy was creative, but the Board apparent thought it was overreaching.

My gut feeling about common meaning is that "same" means "identical" while "common" requires less than identical. But I don't want cases being decided on gut feeling, so definition evidence would have helped here. Not much else to go on, since the spec itself uses "same" exactly once (as pointed out by the Examiner), and only uses "common" once – in the Summary of the Invention.

Often when the Applicant points to a statement in the spec as a reason to narrow a claim term, the Board notes that the relied-upon statement is couched in terms of examples or embodiments. But here the specification sentence that used the word "same" also used the term "invention". So you can't immediately discount the sentence by saying that it referred to a different embodiment than the one claimed.

Should the Applicant have amended the claim to use "same" rather than "common", since that was the meaning he was arguing? After all, hasn't the Applicant given up scope here with a clear disclaimer? Or would this Examiner gave a 112 1st Written Description rejection if the Applicant tried that?