Ed Sheeran Copyright Trial Hinges on Music Experts, Song History

Ed Sheeran’s closely watched music copying trial has featured clashing musicologists whose testimonies will guide a jury tasked with weighing similarities and differences in chord progressions and harmonic rhythms—complex concepts for the untrained ear.

Sheeran has also employed a now-common legal defense among high-profile defendants: arguing that although the chord progressions found in his song “Thinking Out Loud” and Marvin Gaye’s 1973 “Let’s Get It On” are similar, they are found so abundantly across music history that they can’t be protected by copyright.

The trial in Manhattan federal court has mirrored other recent music trials against Pharrell Williams, Robin Thicke, ...