The Board affirmed a refusal to register the design mark shown
below, finding that the design is a graphic tool used by DJs to
discern harmonic compatability, and does not function as a
trademark for "Computer software for music analysis and
processing; computer software for manipulating, mixing, and
performing music and sounds" and for "Providing advice
and information in the field of DJ'ing methodology and the
analysis, selection and arrangement of music and sound
recordings." In re Mixed in Key LLC, Serial No.
87789666 (August 27, 2019) [not precedential] (Opinion by Judge
Jonathan Hudis).

The critical question in failure-to-function cases is whether
the proposed mark would be perceived as a source indicator for the
involved goods or services. To make this determination, the Board
looks to the specimens of record and other evidence to discern how
the proposed mark is actually used in the marketplace.