Different fields of invention may nevertheless provide analogous art when the particular technical problem with which the inventor is involved (as opposed to commercial problems concerning the end-product) is such that the two fields represent a relatively close-knit class of inventions. For example, as here, pressure-resistant caps for liquid chromatography containers and for liquid beverage containers are considered to be a relatively close-knit class of inventions, whereas fasteners for hose clamps and for women’s garments are not.
Background / Facts: The patents on appeal here from rejection at the PTO during reexamination are directed to re-sealable cartridges for low pressure liquid chromatography (LPLC). In particular, the patents describe low cost re-sealable cartridges for LPLC that provide a fluid tight seal under pressure, using “pressure-resistant caps.” The closest LPLC prior art uses pressure-resistant caps but not of the type claimed with complementary inclined sealing surfaces of the cap and the lip of the container. Instead, the Board cited several references directed to “soda-pop” bottles that have a similar design for the similar purpose of sealing fluid under pressure.
Issue(s): Whether the “soda-pop” bottle designs, which are not within the field of the inventor’s endeavor, are nevertheless sufficiently “reasonably pertinent” to the particular problem with which the inventor is involved to qualify as analogous art with respect to the claimed LPLC re-sealable cartridges.
Holding(s): Yes. The Board narrowly characterized the particular problem addressed by the inventor in terms of its technical challenges as how to form “an LPLC cartridge that ‘would allow a user to easily vary and access the cartridge’s contents without destroying its ability to be sealed and function under LPLC pressures.’” Meanwhile, the patentee more broadly characterized the particular problem in terms of its desired end-product as how to “provide chemists with a low cost disposable chromatography cartridge that can function under LPLC pressures and simplify the chemist’s ability to control the chromatographic packing material and the introduction of fluids into the cartridge under pressure.” The court sided with the Board’s narrower, more technical characterization, and found that fluids under pressure is a sufficiently close-knit class of inventions. “Here, the [soda-pop] references address the problem of providing a fluid tight seal at elevated pressures, between a container and a resealable cap. This is sufficiently close to the problem addressed by the claimed invention.”