Legal Definitions - ordinary-observer test

The ordinary-observer test is a legal standard primarily used in copyright law, and sometimes in design patent law, to determine if two works are substantially similar. It asks whether an average, non-expert person, observing the two works side-by-side, would conclude that one work was copied from the other, or that they are so alike as to be the same. The focus is on the overall impression and aesthetic appeal, rather than a detailed, expert comparison of individual elements. This test aims to reflect the perspective of the typical consumer or viewer, not a specialist who might dissect the works for minor differences.

Here are some examples illustrating how the ordinary-observer test is applied:

• Musical Composition Infringement: Imagine a popular new pop song is released, and an independent musician claims it infringes on their earlier, less-known instrumental track. To apply the ordinary-observer test, a court would have a jury or judge listen to both songs. They would consider whether an average listener, without musical training, would perceive the two songs as substantially similar in their overall melody, rhythm, and feel, even if there are some minor differences in instrumentation or arrangement. If the average listener would likely conclude that the new song sounds like a copy of the older one, the test would be met.

• Visual Artwork Copyright: A graphic designer creates a unique logo for a startup company, featuring a distinctive abstract shape and color scheme. Later, a larger corporation launches a new product line using a logo that appears strikingly similar. In a copyright infringement lawsuit, the ordinary-observer test would be used. An average person, viewing both logos side-by-side, would be asked if they appear substantially similar in their overall design, arrangement of elements, and aesthetic impression. The test wouldn't focus on tiny, technical differences that only a design expert might notice, but rather on whether the general visual impact leads an ordinary observer to believe one was copied from the other.

• Design Patent Infringement: A company holds a design patent for the unique visual appearance of its innovative smartphone case, which features a specific texture, contour, and button placement. A rival company then introduces a new smartphone case that looks very similar. In a design patent infringement case, the ordinary-observer test would be applied. A court would consider whether an average consumer, familiar with smartphone accessories, would find the overall appearance of the two cases to be substantially the same. This means assessing if the rival case's design is so similar to the patented design that it would deceive an ordinary observer into believing it is the same product, or a copy of it, based on its visual characteristics, not its functional aspects.