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Specification is the Best Guide to the Meaning of a Claim TermFebruary 17, 2006

In Curtiss-Wright Flow Control Corp. v. Velan, Inc., the Federal Circuit determined the district court erred in its construction of the term ‘adjustable’ and subsequently vacated the district court’s preliminary injunction, remanding the matter. At issue was a Curtiss-Wright patent (”714′) which claimed a system and method for de-heading coke drums without manually removing the heads. (A coke drum is used to collect heated residue from liquid petroleum for conversion into distillates and solid coke.) Coke drums are very hot and the heads can weigh up to four tons presenting many hazards for workers during head removal. In the preferred embodiment of the ‘714 patent, the invention accomplishes a vital adjustment for providing an opening to remove the contents of the coke drum by making the adjustment with an adjustment mechanism.Velan developed valves, which it planned to launch at an industry conference, whereby the valves included upper dynamic, live loaded seats with internal biasing springs. Velan’s valves did not include adjustment mechanisms. To change the biasing force in Velan’s dynamic, live loaded seats, the internal biasing springs had to be replaced by an operator. This replacement required removing the valves from the coke drum.Curtiss-Wright sued Velan claiming that the Velan valve infringed the ‘714 patent, seeking a preliminary injunction to prevent Velan from presenting its valve at the conference. According to the trial court, the term ‘adjustable’ in claim 14 of the ‘714 patent meant that the bias force on the live loaded seat could be changed in a manner that is ‘not limited in any time, place, manner, or means of adjustment.’ Based on this language construction, the trial court concluded that Curtiss-Wright had shown a reasonable likelihood of success on the merits. Thus, Curtiss-Wright’s preliminary injunction was granted. Velan appealed.In arriving at its decision, the Federal Circuit applied the principle, recently reiterated in Phillips v. AWH Corp., 415 F.3d 1301 (Fed. Cir. 2005) (en banc), that the specification is the single best guide to the meaning of a claim term. In this matter, the Federal Circuit looked to several areas of the ‘714 patent specification which described the deficiencies of the prior art, how the present invention overcame these deficiencies, the application of the critical aspect of the invention, and the described embodiments. It found the patent specification consistent, without exception, regarding the adjustment that occurred during operation of the de-header system; specifically noting that nothing in the specification included a structure that required dismantling of the valve to perform the adjustment. The Federal Circuit further noted that the district court impermissibly broadened the meaning of the term ‘adjustable’ through claim differentiation by failing to apply two considerations generally governing this claim construction tool when applied to two independent claims, as in the instant case. The first that claim differentiation takes on relevance in the context of a claim construction that would render additional, or different, language in another independent claim superfluous; and second, claim differentiation cannot broaden claims beyond their correct scope.Because the Federal Circuit found that the district court erred in its claim construction, the subsequent infringement analysis by the district court in the context of Curtiss-Wright’s motion for a preliminary injunction was also flawed. Thus, the Federal Circuit remanded the matter to the district court for action consistent with the opinion.To read the full text of the decision, log on to (

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