Authored by: Jeremy J. Gustrowsky
In a recent decision, the Federal Circuit affirmed the invalidation of two patents owned by Sage Products, LLC, relating to sterilized chlorhexidine products used for skin disinfection. The patents in question, U.S. Patent Nos. 10,398,642 and 10,688,067, covered a sterilized chlorhexidine gluconate composition in an applicator package. The dispute centered on whether a prior art document—a UK regulatory report for ChloraPrep—anticipated Sage’s patent claims by describing a “sterile” product.
Sage argued that the UK report’s use of the word “sterile” did not mean the same thing as “sterilized” under the patents, claiming that those in the field widely believed the ChloraPrep product was not actually sterilized. However, the court agreed with the Patent Trial and Appeal Board that a person skilled in the art, with experience in sterilization processes and knowledge of UK regulations, would have understood “sterile” in the UK context to mean the product met strict sterilization standards. The court noted that UK regulations require products labeled “sterile” to meet a very low probability of contamination, aligning with the patents’ requirements.
The court also found that all elements of Sage’s claims—including requirements for a sterilized colorant and a specific sterility assurance level—were disclosed in the prior art, either explicitly or as understood by a skilled artisan. The Board was permitted to rely on expert testimony and other evidence outside the four corners of the prior art document to interpret what it would have meant to someone skilled in the field.
Ultimately, the Federal Circuit rejected Sage’s arguments about procedural errors and enablement, finding that the Board’s decisions were supported by substantial evidence. The court’s ruling highlights the importance of understanding how terms like “sterile” are interpreted in different regulatory contexts and how expert knowledge can be used to fill in gaps in the written record.