In the bad old days of music copyright, a small fortune could be made by musicologists and copyright lawyers arguing over chord progressions, melody similarities, “feel” and “groove”, and so on. Juries often had no idea what these specialists were talking about, or whether compositional similarities necessarily crossed the blurred lines between “reminiscent of”, “inspired by”, and “copied from” (see what I did there?), which is why the family of late singer Marvin Gaye managed to win a lawsuit over the Robin Thicke/Pharrell Williams song “Blurred Lines”, despite there being no specific examples of technical musical infringement between the two compositions.Because both songs used percussive elements of syncopated cowbell and similar rhythms, and a heavy bass line played on an electric piano, the songs were found by a jury to have a similar “feel” - similar enough to win Gaye’s estate USD$5.3M and 50% of all future royalties. Similar enough, to the untrained ear.A more pertinent melodic infringement example would be the battle between Tom Petty and Sam Smith over the chorus hook in Smith’s song “Stay with Me” sounding strikingly like Petty’s “Don’t Back Down”. That dispute settled out of court with Smith giving Petty a co-writer credit, all for a six-note melodic hook in the chorus that sounds close to each other in both songs. Close counts in horseshoes and hand grenades, as they say, and until now it could also make or break a copyright lawsuit. That’s all about to change.The problem with melody copyright is that the western chromatic scale only has 12 tones (or 8 notes) in it. Conceivably there are a finite number of melodies that could be exhausted relatively easily. A quick google search of music copyright cases will show it to be a strikingly common occurrence that musicians often echo each other subconsciously, or even completely accidentally. There are only so many combinations of 12 tones, after all.There are so many traditional melodies in folk music, country, orchestral themes, pop anthems, and hybrid genres of all kinds circling around on the radio and in popular culture. Repeating a few notes here or a couple of bars there is all but inevitable. With the “close enough” approach to melody, artists were open to lawsuits every time they released a recording.In one of the most interesting moves in music copyright ever to have hit the internet, two musicians have used an algorithm to generate every possible remaining melody above the middle-C octave in the 12-tone western scale as MIDI files. Every single one. The two have released more than 68 billion files under a Creative Commons Zero license, allowing anyone in the world to use them as they see fit, but not to copyright them privately.The two people involved, musician/programmers Damien Riehl and Noah Rubin, were fed up with melody copyright battles and the chilling effect such lawsuits have on the creative process of songwriters and musicians and wrote the algorithm to “brute force” their way to a solution.The logic behind this move is the idea that numbers, for example, aren’t copyrightable because they are facts - concepts that have existed since the dawn of time. Similarly, says Riehl, notes are also facts. Under that line of thinking, notes exist in and of themselves and shouldn’t be copyrightable at all. The pair of musical programmers admit that it’s not certain that their project, called All the Music could be used as a viable defense in a copyright lawsuit, but we have yet to see the effect of this development in the jurisprudence. However, the zeal with which some artists have pursued suing each other over basic musical concepts is sure to be diminished, which is nothing but good news to songwriters everywhere.