The U.S. Court of Appeals for the Federal Circuit has declined to reconsider its earlier decision that invalidated a $14 million judgment against LG Electronics Inc. in a patent infringement case brought by Mondis Technology Ltd. The court’s refusal to rehear the case leaves intact its August ruling, which found that Mondis’ U.S. Patent No. 7,475,180 lacked an adequate written description, rendering the patent claims invalid.
The patent in question pertains to a system for controlling display units, such as computer monitors, by utilizing identification numbers stored within the display unit’s memory. During the patent’s prosecution, Mondis amended the claims to include an “identification number for identifying at least a type of said display unit.” This amendment was intended to overcome prior art rejections. However, the Federal Circuit determined that the patent’s specification did not sufficiently support this “type” limitation, leading to the conclusion that the claims were invalid for lack of written description.
In its August opinion, the Federal Circuit emphasized that “no reasonable jury could find the patent’s written description conveys to a relevant artisan that the inventors possessed the type limitation.” The court further noted that while a patent is presumed valid, this presumption does not relieve the patentee of the burden to demonstrate adequate written description support when the patent itself fails to do so. The court stated, “Sometimes the patent itself is clear enough that it establishes inadequacy of support in the written description for the full scope of the claimed invention unless there is contrary evidence.” ([cafc.uscourts.gov](https://www.cafc.uscourts.gov/08-08-2025-23-2117-mondis-technology-ltd-v-lg-electronics-inc-opinion-23-2117-opinion-8-8-2025_2555742/?utm_source=openai))
Mondis had argued that the patent examiner’s allowance of the amended claims without objection provided a heightened presumption of validity. However, the Federal Circuit rejected this reasoning, clarifying that an examiner’s allowance does not, by itself, provide substantial evidence that the claims comply with the written description requirement. The court explained, “The examiner’s allowance of claims by itself does not provide substantial evidence that the claims comply with the requirements of § 112.” ([knobbe.com](https://www.knobbe.com/updates/federal-circuit-review-august-2025/?utm_source=openai))
This decision underscores the critical importance of ensuring that patent specifications fully support all claim limitations, particularly when amendments are made during prosecution to overcome prior art. For legal professionals and corporate counsel, the ruling serves as a reminder to meticulously assess the written description support for each claim element to withstand potential validity challenges.