June 8, 2018
Authored and Edited by David R. Lefebvre; Kevin D. Rodkey; Elizabeth D. Ferrill
In D Three Enterprises, LLC v. Sunmodo Corp., Nos. 2017-1909, -1910 (Fed. Cir. May 21, 2018), the Federal Circuit affirmed the district court’s summary judgment determination that the asserted claims could not claim priority from D Three’s 2009 Application because it did not provide written description support for the asserted claims—rendering the claims invalid based on intervening prior art.
D Three sued Sunmodo, alleging infringement of several patents directed to roof mount sealing assemblies. The patents claimed priority to D Three’s 2009 Application, which disclosed one washerless assembly that required a specific bracket and other assemblies having a washer only above a flashing component. The district court found that the 2009 Application did not provide written description support for the later-filed patents with claims directed to generic washerless assemblies and assemblies with washers below the flashing and that the claims were invalid based on intervening prior art.
On appeal, D Three argued the 2009 Application’s language regarding “modifications, permutations, additions, and sub-combinations” supported the broader claims to washerless assemblies. The Federal Circuit rejected D Three’s argument as “boilerplate language,” explaining that the 2009 Application did not adequately disclose other washerless assemblies or assemblies with a washer below the flashing. The court explained that “[i]t is not sufficient for purposes of the written description requirement of § 112 that the disclosure . . . would lead one to speculate as to the modifications that the inventor might have envisioned, but failed to disclose.” Accordingly, the court affirmed the district court’s finding that the 2009 Application did not provide written description support for the asserted claims and the claims were invalid based on intervening prior art.
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