Kingsdown Medical Consultants, Ltd. v. Hollister Inc. 863 F.2d 867 (Fed. Cir. 1988) Kingsdown filed a patent for a medical device. They made a bunch of claims, some of which were allowed by the patent examiner and some of which were rejected. After they had filed the patent, Kingsdown found a similar medical device being made by Hollister. Kingsdown started amending their application to cover Hollister's device. Kingsdown went back and forth with the patent office for a while, amending claims to try to get them approved (a continuation). They also started renumbering claims and it started to get confusing. At a certain point, Kingsdown made a list for the patent examiner of all the claims that had been previously approved and all the ones they were amending to try to get approval for. One of the claims that had been rejected was placed on the list of claims that had been approved. The patent examiner didn't notice that a previously rejected claim was on the list of approved claims, and so it was never looked at. The patent was granted. Kingsdown then sued Hollister for infringement. As part of discovery, Hollister noticed that the rejected claim was in the granted patent. They argued that Kingsdown's patent was thus invalid. Kingsdown was specifically asserting the rejected claim against Hollister. The Trial Court found for Hollister. Kingsdown appealed. The Trial Court found that Kingsdown's conduct met the intent element of inequitable conduct because of their gross negligence. The Court found that Kingsdown's acts indicate an intent to deceive the USPTO. The Court found that it was shady for Kingsdown to try to amend their patent to cover Hollister's device. The Court struck down the entire patent, because inequitable conduct invalidates the entire patent, not just the claim that was questioned. The Appellate Court reversed. The Appellate Court found that gross negligence was not enough to justify a finding of intent to deceive. Instead, the courts must look at all the evidence that surround the conduct in order to make a determination of culpability. The Court found that the error was just a ministerial error and was hard to catch. The Court found that the mistake must be material. In this case, the claim had been rejected for indefiniteness, and in general that's not all that big of a deal. Claims that are rejected for lack of definiteness can usually be approved by making a few minor changes. The Court found that there was nothing improper in Kingsdown trying to cover Hollister's device.