Even statistically insignificant relationships disclosed in the prior art can be relied on for establishing that the relationship was known. Here, for example, a prior art document showing effectively no change in permeability was found to contain sufficient data for one skilled in the art to recognize the relationship underlying the claimed subject matter.

Background / Facts: The patent being asserted here is directed to gatifloxacin, an aqueous liquid pharmaceutical eye drop composition, with added disodium edetate (“EDTA”). In response to a defense of obviousness, the appellants argued that nothing in the prior art reasonably suggested that the claimed limitations of 0.01 w/v% EDTA at pH 5-6 would have any effect in improving gatifloxacin’s corneal permeability in vivo. In fact, the appellants argued, the prior art expressly taught that these claimed limitations would have no effect on corneal permeability.

Issue(s): Whether statistically insignificant relationships disclosed in the prior art can be relied on for establishing that the relationship was known.

Holding(s): Yes. “Appellants improperly focus on the percentage change in permeability over the control, which was zero for both methanol and glycerol, to conclude that the data showed no increase in corneal permeability. In reality, though the percent changes were not statistically significant, appellees set forth expert testimony that a person of ordinary skill would have recognized from the data that 0.01 w/v% EDTA would increase corneal permeability.”

Full Opinion