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Written Description Is Important In Construing Claim Terms

Client Alert | 1 min read | 06.23.06

In Honeywell International, Inc. v. ITT Industries, Inc. (No. 05-1407; June 22, 2006), the Federal Circuit affirms a district court's grant of summary judgment of non-infringement of U.S. Patent No. 5,164,879 whose claim 1 is directed to a fuel injection system component communicating fuel to the engine of a motor vehicle.

The Federal Circuit agrees with the district court's construction of the term “fuel injection system component” as being limited to a fuel filter. The written description of the application refers to the fuel filter as “this invention” or “the present invention” several times. Further, the written description is not seen as indicating that a fuel filter is merely a preferred embodiment of the claimed invention. A broader statement made by the patentee during prosecution of the application that the claims cover “ all fuel components manufactured of the moldable material disclosed and claimed in the specification” is considered to be ambiguous and possibly inconsistent with the written description, and thus entitled to little weight. Also, little weight is assigned to the patent examiner's restriction requirement during prosecution, with respect to claims for a “fuel filter” and a “fuel system component,” because the examiner did not construe the meaning of these terms.

The accused products are “quick connects,” which are nut-like structures that join various components of a fuel injection system together, such as a fuel line to a fuel filter. Because the quick connects do not filter fuel, they are found not equivalent to the fuel filter of claim 1.

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Client Alert | 8 min read | 06.30.25

AI Companies Prevail in Path-Breaking Decisions on Fair Use

Last week, artificial intelligence companies won two significant copyright infringement lawsuits brought by copyright holders, marking an important milestone in the development of the law around AI. These decisions – Bartz v. Anthropic and Kadrey v. Meta (decided on June 23 and 25, 2025, respectively), along with a February 2025 decision in Thomson Reuters v. ROSS Intelligence – suggest that AI companies have plausible defenses to the intellectual property claims that have dogged them since generative AI technologies became widely available several years ago. Whether AI companies can, in all cases, successfully assert that their use of copyrighted content is “fair” will depend on their circumstances and further development of the law by the courts and Congress....