There was quite a lot of discussion about a month ago on music plagiarism and copyright infringement in the wake of Joe Satriani's lawsuit against Coldplay, so I thought it would be helpful if I set out a basic outline of the law on copyright infringement, with emphasis on how it applies to cases of music plagiarism. The summary of law given here is based on Malaysian law (because that's what I studied) but it should be more or less the same for the US and the UK (Malaysia inherited a lot of law from the UK) as well as other Commonwealth countries, unless said countries have passed some other weird and wonderful laws affecting copyright.
To establish a claim of copyright infringement, you, the plaintiff, have to prove five things: (1) that you own the copyright in your work; (2) that your work is original; (3) that the defendant copied the work; (4) that there is substantial similarity between your work and the defendant's work; and (5) that the part copied by the defendant was a substantial part of your work.
As to requirement (1), you basically acquire the copyright in your song once you have put it into a fixed form, e.g. in writing or in a recording. Registration and other formalities are generally not necessary for you to acquire the copyright. However, registration of the copyright will come in useful as evidence to show that you do own the copyright. I've heard people recommend that you mail the composition to yourself so that the postmark will serve as evidence of the date on which you wrote or recorded the song; however, this evidence won't be considered 100% conclusive as the court has to bear in mind that there are ways of tampering with sealed envelopes and postmarks.
As to requirement (2), originality does not mean that you need to write songs of Dylanesque or Hendrixian genius; it simply means that the song must have come from you and that you must have put some effort into it. As long as *you* didn't copy the song from some other source yourself, this requirement should be quite easy to fulfill. This may account for the myth that you can't copyright chord progressions. It's generally true that chord progressions aren't 'original' enough to be copyrighted, since most of rock music is based on the same few progressions, but it's not impossible - someone, somewhere, might someday come up with some weird, hitherto unheard of chord progression that will catapault them into stardom overnight.
On to requirement (3). Since it's rarely possible to show that the defendant actually sat down with your song and copied it note for note, what is usually required is for you to show that the defendant had access to it. You could show, for instance, that you or a friend or acquaintance of yours had sent the defendant a copy of your song; or you could show that your song was so widely available (e.g. lots of radio airplay) that he would have a reasonable chance of hearing it. There's also a school of thought which says that if the songs are very similar, the court should be able to draw an inference that the defendant did have access.
'Substantial similarity' in requirement (4) means that there should be a high degree of similarity between the two songs which is more likely to be the result of copying rather than mere coincidence. In considering whether there is substantial similarity, features that are commonplace and unoriginal are usually disregarded (again, this may account for the 'you can't copyright chord progressions' myth).
Requirement (5) seems to have given rise to the myth that you cannot copyright less than four bars of a song. Actually, as long as the part copied by the defendant is distinctive enough that it is recognisable as your song, that amounts to a substantial part. It could be one bar, or a short sequence, or 20 seconds of a four-minute long composition - the length doesn't matter as long it's sufficiently distinctive, preferably so distinctive that people will nudge you and ask: 'Hey, isn't that your song?'
Let's see how all this applies to Satriani v Coldplay. Requirements (1) and (2) are no-brainers - no one's claiming that Satriani didn't write 'If I Could Fly' or that it isn't original. Requirement (3) might be a bit tricky; Satriani's music isn't exactly blasting out from every radio channel 24/7. But then again, it isn't all that obscure or hard to get either. What with rumors and denials of Chris Martin being seen at a Satriani concert, it all boils down to a question of how much evidence Satriani's legal team can produce. Requirements (4) and (5) will ultimately be left up to the court to decide - in the meantime, we can all listen and form our personal opinion, of course.
A selection of cases on music plagiarism have been helpfully provided by the UCLA Law Copyright Infringement Project. They're generally not very long and make for fairly interesting reading.
Disclaimer: This article is intended for general information and is not meant as a substitute for a professional legal opinion. I'm only someone who has studied law and is interested in guitars, music, copyright and the music industry.
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