Addressing adequacy of a written description to support a claim of priority, the US Court of Appeals for the Federal Circuit upheld a grant of summary judgment finding that boilerplate language in the asserted priority document could not be relied on to support the later claims, and that the asserted claims were therefore invalid in view of the accused structures. D Three Enterprises, LLC v. SunModo Corp., and Rillito River Solar, LLC DBA EcoFasten Solar, Case Nos. 2017-1909; 17-1910 (Fed. Cir., May 21, 2018) (Wallach, J).

D Three Enterprises sued SunModo and Rillito River Solar (together, appellees) for infringement of three D Three patents. Appellees filed a joint motion for summary judgment, arguing that the priority claim of the asserted patent to the common priority 2009 application was invalid, and therefore the asserted patents were not entitled to the claimed priority date and the asserted claims were invalid as anticipated by the allegedly infringing products (which were on sale prior to asserted patents' actual filing date).

To determine whether the asserted claims could claim priority from the 2009 application, the district court divided the asserted claims, which relate to roof mount sealing assemblies, into two categories: (1) claims that do not recite a washer and do not limit a type of attachment bracket, and (2) claims that do recite a washer and do not limit its location. The district court determined that only one washerless assembly was disclosed in the 2009 application, which consistently described a single type of attachment bracket and taught that when a washer is present in an assembly, the washer is only above a flashing component.

The district court concluded that the 2009 application disclosure was limited to (1) assemblies with no washer, but requiring a W-pronged attachment bracket, and (2) assemblies with washers that are only located above a flashing component. Accordingly, the district court granted the motion, finding that the asserted claims lacked support in the 2009 application and were therefore invalid over the accused devices. D Three appealed.

With regard to asserted claims that do not recite a washer and do not limit a type of attachment bracket, the Federal Circuit agreed with the district court that the 2009 application "in no way contemplates the use of other types of attachment brackets in a washerless assembly," and never describes any other types of attachment brackets that could be used. The Court went on to explain that the absence of an admission that various attachment brackets cannot be used in a washerless system is insufficient to provide written description, and that boilerplate language regarding "modifications, permutations, additions and sub-combinations" is also insufficient to show adequate disclosure of the actual combinations and attachments used in the asserted claims.

With regard to asserted claims that recite a washer in a location other than above a flashing component, D Three did not contest that the 2009 application disclosed a washer "only above the flashing." However, D Three asserted that adequate written description support was provided by a disclosure of systems without a washer and with a washer located above the flashing. D Three also argued that the application did not "require the washer to be atop the flashing as opposed to below." The Federal Circuit rejected these contentions, explaining that the "lack of any disclosure of an assembly with a washer below the flashing, or statement on the flexibility of the position of the washer, is fatal to D Three's argument." Rather, "demonstrating adequate written description 'requires a precise definition' of the invention." It is not sufficient "that the disclosure, when combined with the knowledge in the art, would lead one to speculate as to the modifications that the inventor might have envisioned, but failed to disclose."

Accordingly, the Federal Circuit concluded that the asserted claims lacked sufficient written description support in the 2009 application, were not entitled to claim priority from it, and were therefore invalid.

Practice Note: When drafting a patent, be sure to include several alternative structures or species of a feature rather than relying on boilerplate language.

Inadequate Written Description Means Claim Of Priority Is All Washed Up

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