This morning the Federal Circuit issued one nonprecedential opinion in a patent case. Here is the introduction to the opinion.

Pacific Coast Building Products, Inc. v. CertainTeed Gypsum, Inc. (Nonprecedential)

Pacific Coast Building Products, Inc. (Pacific Coast) sued CertainTeed Gypsum, Inc. and Saint-Gobain Performance Plastics Corp. (collectively, CertainTeed) for patent infringement of claim 21 of U.S. Patent No. 9,388,568 (the ’568 patent) in the United States District Court for the Northern District of California. Claim 21 is directed to a drywall structure having a “scored flexural strength” of “about 22 pounds per 1/2 inch thickness of the structure.” Pacific Coast appeals from the district court’s claim construction order, which found the claim term “scored flexural strength” indefinite.

We agree with the district court that there are multiple ways to measure “scored flexural strength” and that the specification’s lack of guidance for choosing which measurement to use renders claim 21 indefinite. Accordingly, we affirm the district court’s invalidity finding.