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Who is a skilled artisan?
In patent law, a “person of ordinary skill” (also known as a “skilled artisan”) is a hypothetical person presumed to have known the field of an invention at the time of its patenting. If an invention would have been obvious to a skilled artisan, it’s unpatentable.
But how the Patent Trial and Appeal Board (PTAB) interprets the qualifications of a so-called person of ordinary skill can seem to strain the definition of “ordinary.” That’s what a patentee recently argued to the U.S. Court of Appeals for the Federal Circuit.
The nitty gritty
Sage Products LLC holds two patents related to a “sterilized” chlorhexidine product in a package, such as an applicator filled with an antiseptic composition for disinfecting skin. A product may be referred to as “sterilized,” according to the specification for both patents, “where such sterility can be validated.”
A medical technology company sought inter partes review (IPR) of the patents. Under IPR, the PTAB can reconsider and cancel an already-issued patent based on certain types of “prior art” that make the invention obvious. The board’s final decision is subject to review by the Federal Circuit.
The PTAB found the challenged patent claims were unpatentable. It relied heavily on a report, or prior art, issued by the United Kingdom’s (UK’s) Medicine and Healthcare Products Regulatory Agency about a product called ChloraPrep. The report states that the product is a “sterile” antiseptic solution and refers to the applicator as “sterile until the packaging is opened.” The board also cited a British Standard that establishes the UK’s requirements for labeling a medical device as being sterile.
Sage appealed. The director of the U.S. Patent and Trademark Office intervened and stepped in after the original challenger withdrew.
A sterile reading
Sage argued that the PTAB incorrectly interpreted its definition of a skilled artisan to include familiarity with UK regulations that Sage asserted a skilled artisan would lack. The Federal Circuit, however, agreed with the PTAB that a skilled artisan would have known, through education and experience, that the term “sterile,” as used in the UK report, was equivalent to the term “sterilized,” as used in the United States and in the Sage patents.
Both Sage’s expert and the PTAB defined a skilled artisan as having a bachelor’s degree in pharmaceutical or similar sciences and at least four years of experience with sterilization processes. The Federal Circuit found that a skilled artisan would know about the differing regulatory requirements in the United States and the UK. And this individual would recognize that the UK report, about a UK medical product, would need to satisfy UK regulatory standards to be labeled as sterile.
The court pointed to the substantial evidence supporting the board’s position, including testimony from the original challenger’s expert witness. He testified that a skilled artisan would know that the report’s references to “sterile” items would satisfy the patent claims’ requirement for “sterilized” items.
Keep it clean
Would-be patentees shouldn’t assume they understand how the PTAB or a court will interpret “skilled artisan” for purposes of their patents. Instead, it’s important to conduct thorough searches for prior art and proceed accordingly.
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