The Commissioner of Patents refused to issue a patent to SmithKlineBeecham for Patent Application No. 2,368,934 (the ’934 Application), titled "Metered Dose Inhaler [MDI] for Fluticasone Propionate" on the basis of obviousness double patenting over Patent No. 2,217,948 (the ’948 Patent), the parent of the ’934 Application, and Patent No. 2,447,517, the divisional of another divisional of the ’948 Patent. The Patent Appeal Board ("PAB") noted that the prohibition against double patenting could exist notwithstanding the fact that the patent would expire on the same date as the other patents, thus resulting in no prolongation of monopoly. The PAB did not agree with the Examiner that an element of a claim is non-essential simply because it is known in the art. The PAB further found that, while an analysis of double patenting is based on a comparison of the claims, claims are to be construed in accordance with the principles of purposive construction, which includes taking into account the patent specification as a whole. The PAB concluded that the claims of the ’934 Application are not patently distinct from the claims of the cited patents.

Commissioner's decision #1328.