It appears, in my experience, that there is confusion regarding this section of the MPEP and it would be very helpful to examiners if the MPEP would provide a more extensive discussion of preambles, intended uses and when statements in preambles actually limit the claimed Invention. Quite respectfully, the statement in the MPEP, upon citing In re Schriber, indicates 'If a prior art structure is capable of performing the intended use as recited in the preamble, then it meets the limitation of the claim' without more explanation, is sometimes erroneously interpreted as meaning the antithesis; i.e., that 'if a prior art structure is NOT capable of performing the intended use, the structure does not meet the claim.' However, what is not discussed in this MPEP section is that in In re Schriber, the court determined that the intended use was a claim limitation only because applicants, during prosecution, relied upon the intended use to distinguish their invention from prior art apparatus and that this reliance 'transformed' the intended use into a claim limitation. It appears that as a whole (my opinion of the case law), the courts have determined that intended uses do not limit product claims unless the intended use meets certain criterion: a) the body of the claim has antecedence back to the intended use which subsequently may transform the intended use into a claim limitation b) when the claim is a Jepson claim and c) when Applicants on the record, during prosecution, (convincingly? this is not clear) distinguish their invention from the prior art based upon the intended use of their claim(s). Thus, it appears that Examiners must first determine IF the intended use limits the claimed Invention by subjecting the intended use to the inquiries provided by the courts. Further review and analysis of relevant case law pertaining to this section to provide more detailed discussion and more examples in this section, in any manner in which the Office deems appropriate and applicable, would help examiners determine the proper scope of the claimed invention which in turn, will help examiners carry out proper claim construction.
Idea No. 157