Reciting Ranges in Chemical Patent Applications and the 112 Rejection

Written by: Mark Terry

What happens when you only disclose a larger range of values in the specification and later amend the claims to recite a smaller range of values encompassed by the larger range? Do you run into a 112 written description problem? That was the issue in today’s Ex Parte Moraes Barros (BPAI 2010-006399) decision at the Board of Patent Appeals and Interferences (BPAI) where a Patent Examiner was reversed. As a Florida Patent Attorney, I stay updated on the latest decisions of the BPAI, so as to provide my clients with the best representation on appeal.

In the Moraes Barros case, the Applicant claimed a chemical composition that recited a range of values for a chemical. The problem is that the specification only disclosed a larger range that encompassed the smaller range that was recited. Consequently, the Patent Examiner rejected the smaller range under the 112 written description requirement because he believed there was no support for the smaller range.

The BPAI reasoned: “The original disclosure of a broader range may support the recitation of a narrower range, even though the narrower range had not been explicitly disclosed. In re Wertheim, 541 F.2d 257, 262-63 (CCPA 1976). However, as noted in Wertheim, determination of questions relating to the written description requirement depend upon the facts of each particular case (id.) … We note that a range is a shorthand format for presenting information, where the range is understood to encompass each discrete point.” In light of the above, the BPAI agreed that the smaller range was adequately disclosed in the specification and thus reversed the Examiner’s 112 rejection of the claims.

Lessons Learned: The educational moment in this case is the fact that, at least when it comes to 112 rejections based on the written description requirement, you need not disclose each and every permutation of a range of values when writing a chemical application. A well-crafted description of a range of values should suffice.


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