The US Court of Appeals for the Federal Circuit reversed the district court’s decision that the claim term “visually negligible” was indefinite because the specification provided examples of visually negligible indicators, and concluded that neither the examiners nor the experts during prosecution and reexamination had apparent difficulty determining the scope of this term. Sonix Technology Co., Ltd. v. Publications International, Ltd., Case No. 16-1449 (Fed. Cir., Jan. 5, 2017) (Lourie, J.).

The patent at issue describes a system and method for using a “graphical indicator” to encode information on the surface of an object. The inventor recognized that encoding information on the surface of an object is not new. For example, the patent describes a bar code as a conventional example of a graphical indicator. However, the patent purports to improve on conventional methods by rendering the graphical indicator visually negligible. Specifically, the graphical indictor can be a unique matrix of micro-unit dots, where the dots are so small that human eyes cannot differentiate one graphical indicator from others. The patent describes the micro-units as preferably being small enough that only a microscope can detect them, and includes two examples of such visually negligible indicators.

After two reexamination proceedings confirmed that the patent was not invalid in light of the cited prior art, the plaintiff filed suit against the defendant. Subsequent to the district court’s claim construction ruling and after expert reports were submitted, the plaintiff’s expert was asked, during his deposition, what “visually negligible” meant to him. He explained that he understood it to mean that “if these dot patterns are imprinted on a surface, with a cursory look, I will not notice” them. The expert went on to explain that there “is not a universal standard by any means because it depends on the visual acuity of the observer.” Based on this testimony, the district court granted summary judgment that the term “visually negligible” was indefinite and entered a judgment of invalidity. Sonix appealed.

Citing to the Supreme Court of the United States’ 2014 Nautilus decision, the Federal Circuit explained that in order to survive an indefiniteness challenge, a claim “viewed in light of the specification and prosecution history, [must only] inform those skilled in the art about the scope of the invention with reasonable certainty,” and that the challenger must prove indefiniteness by clear and convincing evidence. The Court agreed with the plaintiff that a skilled artisan would understand, with reasonable certainty, what it means for an indicator in the claimed invention to be visually negligible.

The Federal Circuit found that the challenged term was not “purely subjective” because there is an objective baseline to determine what is visually negligible based on what can be seen by the normal human eye. The Court also relied on the fact that the patent specification provided two examples of visually negligible indicators. Finally, the Court observed that no one involved in either of the reexamination proceedings had any apparent difficulty in determining the scope of the term. Based on these facts, the Federal Circuit found that the term was not indefinite and reversed the district court’s summary judgment decision.

Finally, the Federal Circuit noted that the holding in this case does not mean that the existence of examples within the specification will always render a claim definite, or that listing requirements will always provide sufficient clarity. In addition, the fact that an expert applied a contested claim term without difficulty does not render a claim immune from indefiniteness challenge, the Court noted. These factors should be considered in determining whether a claim term is indefinite, however.