Kim v. ConAgra (Fed. Cir. 2006).
Here’s another case where technicalities of the patent system apparently trapped an unsuspecting patentee.
“[W]e reject Kim’s position that she should be treated differently from other patentees because she was pro se during some parts of the prosecution.”
Potassium bromate has been traditionally used in bread-making, but people are concerned with its carcinogenic effects. Yoon Ja Kim, a chemist, found that a combination of ascorbic acid and food acid could serve the purpose of potassium bromate. (i.e., to “strengthen dough, increase loaf volume, contribute to fine crumb grain, and increase shelf life”). Kim filed a pro se patent application and got her patent.
Kim then sued ConAgra — asserting that “Healthy Choice” brand breads infringed on the patent. A jury then found that the patent was not invalid and infringed. The district court, however granted JMOL of non-infringement in ConAgra’s favor. Kim appealed.
Claim Construction and Infringement: The asserted claims both appeared as follows:
A potassium bromate replacer composition consisting essentially of . . .
Although not defined in the specification, CAFC found the preamble term “potassium bromate replacer” to be limiting to the extent that any infringing composition must “perform essentially the same function in the production of that bread as would potassium bromate.”
Kim, acting as her own expert witness, showed that the accused products included the same ingredients as listed in the claims (and that potassium bromate was not an ingredient). However, Kim did not prove that those ingredients were functionally active in the accused products.
Then, the court found that other ingredients, such as vital wheat glutten, ferrous sulfate, and dough strengthening enzymes, might be active. If that is the case, Kim’s “consisting essentially of” transition language would remove those from the ambit of infringement.
Validity – Recapture: Even though the court found no infringement, it went-on to discuss validity. Kim’s patent is a reissue, and the defense argued that the patent violated the rule against recapture. That rule forbids a reissue applicant to recapture scope surrendered during prosecution unless it was “erroneously excluded from that patent.”
Prior precedent made this look like a subjective rule — it is not. “Surrender” means that an objective observer who is later “looking at the prosecution history would conclude that the purpose of the patentee’s amendment or argument was to overcome prior art and secure the patent.” According to the CAFC, the objective standard gives the public more clarity as to when they can rely on a patentee’s admission during prosecution. Interestingly for Kim, he would have lost under the subjective standard, but wins under an objective standard [for reasons too long to describe here.]
Dissent by Judge Schall: Schall would not have included the extensive functional limitation of the preamble potassium bromate replacer because “Kim acted as her own lexicographer in defining the term ‘potassium bromate replacer’ as ‘a slow acting oxidant that is functional throughout the entire manufacturing process.’”
My question is: Have you looked at the ingredient list of your bread lately?