Court Opinion

ID: 9491543
Source: CourtListenerOpinion
Date Created: 2023-08-05 14:16:54.637498+00
Date Added: 2024-06-11T17:54:48.278173
License: Public Domain

MICHEL, Circuit Judge,
dissenting.
I cannot join the majority opinion which upholds a jury verdict of non-infringement which no reasonable jury could have reached. Our precedent is well settled that when a chemical invention is claimed using “consisting essentially of’ language, the mere presence of an additional, unclaimed substance— here, iron sulfide — does not avoid infringement unless it has a “material” effect on the basic and novel properties of the claimed invention. No reasonable jury could hold that an alteration in the dominant wavelength of the glass from approximately 500 to approximately 503 nanometers, and alterations in the u}traviolet and visible light transmittance on the order of 0.5% represent a material effect on the properties of the glass considered in light of the patent. The specification recites a range of 495 to 535 nanometers and the specific language of the claim describes a glass with ultra-violet transmittance of no greater than 31% and visible light transmittance of at least 70%. The written description specifies that sodium sulfate, the precursor of the non-claimed iron sulfide, is to be used a§ a fining agent in heating the ingredients of the glass and does not have a material effect on transmittance properties.
I believe that if the court had provided a proper definition of materiality in its jury instructions, a finding of infringement would have resulted. Similarly, if on post-trial motion for judgment as a matter of law of literal infringement the court had applied the correct definition of materiality in the context of the claims and written description of this patent, it would have granted the motion. Because the court did neither, I would reverse and direct the district court to enter a liability judgment of literal infringement and proceed to decide damages.