It's three in the morning and you've just put the finishing touches to what you're sure is the best song you've ever written. You switch off your computer/close the lid of the piano/lay down your guitar (or just stop whistling - it doesn't much matter) and get ready for a good night's sleep, secure in the knowledge that this is going to be the one that makes your name.

But what if your idea gets stolen? What if, unconsciously, you have ripped-off someone else's theme? What if you've deliberately quoted another artist's melody or words, either as a tribute, or for comedy purposes? What, come to that, if you've gone the whole hog and used a sample?

As we found with musician's insurance a couple of issues ago, there is often more to what seems a straightforward subject than meets the eye and copyright is most certainly not an exception. It's an area that needs expert comment too - after all, your career and your fortune could be at stake. So, what you need here isn't a journalist - it's a lawyer. But not (with all due respect) the chap down the road who specialises in house conveyancing or car accident claims. Music business law - and copyright in particular - is a specialist area and to save you the trouble (not to mention the expense!) of finding an expert, I've plagued one for you: Ms. Kate Westwood, who is a partner in the leading London-based entertainment industry law firm, Dean Marsh & Co. and who very kindly offered to field some of my layman's questions on your behalf.

I started by going back to the one thing that probably most of us know - the old bar room legend that you should post yourself a copy of your song, either as a manuscript, or on a tape or disc, by Special Delivery post, making sure the delivery is signed for and that you keep the unopened envelope as proof of the date you wrote the song. Is that just an old songwriter's tale, or is there some truth in it?

'Yes, as easy as this may seem it does afford some protection against a dispute as to ownership,' Ms. Westwood says. 'The postmark of a sealed unopened letter will go some way to show the approximate date of authorship. It might also be worth including any supporting material such as recording studio invoices or hand written material. To avoid any allegations of tampering with the self addressed envelope method the artist could also deposit the sealed and dated envelope with a lawyer, however not all lawyers will offer this service unless you are already their client and those that do will probably charge a fee.

'It's worth noting that in America there is a separate copyright library to which artists can send their copyright works to make a public record of their registration of copyright, although this is not a condition of copyright protection. You can register it with the Library of Congress, Copyright Office, 101 Independence Avenue, S.E. Washington, D.C. 20559-6000.'

Generally speaking, I asked, how does she think songwriters should go about securing copyright on their material?

'In order for a musician/songwriter to understand how best to protect their copyright in a song it's necessary to understand how copyright is created.

'In order to create copyright in a song the song must actually be reduced to a material form, therefore, once the words and music to a song is either written down or recorded then the creator of them will hold the copyright. If a song is merely sung live at home or at a gig but never written down or recorded then it is not protected by copyright even if it has been performed a thousand times.'

It was at about this point that I began to realise just how profound and deep was my own ignorance. Naively, I'd always assumed that a song was copyrighted the moment you had finished composing it. As this, pretty clearly, isn't the case, what on earth does one do?

'Well, artists should therefore, reduce their songs to a material form (whether the music, lyrics or both) and as you said earlier, post either a tape or manuscript of it to themselves to be kept in a sealed and unopened envelope,' Ms. Westwood says.

'When sending out work, you can also put a copyright notice on your work "©2002 Your Name". This won't necessarily stop someone from appropriating the work but it does notify the receiver who the copyright owner is, and shows that the artist is aware of their rights.

'This may all sound relatively simple but the reason things become complicated and the reason why there are often many disputes over copyright is that a song holds not just one but may different types of copyright including the lyrics, music, the actual recording of the song and all the performances on the recording. There may also be more than one author of the music and the lyrics.'

So what about quoting somebody else's material, whether as actual sampling, or just by using a riff as a tribute?

'There are two types of sampling,' she says. 'The first is where an artist directly uses a recording of another artist by sampling the actual sound itself, this can be a vocal, drum pattern, guitar riff or the whole piece of music. This will be an infringement of the sound recording copyright.

'The second type of sampling happens when an artist takes a piece of music and replays it or re-performs it in an identical way. This will be an infringement of the musical copyright in the music and a literary copyright in the words.

'Even if you only sample a couple of notes or a few seconds of someone else's work this does not mean that you do not need to obtain a licence from the relevant copyright owner to use it. The test applied is whether or not you have sampled a "substantial part" of the work used. This is a question of the quality of the part sampled and not only the quantity and there is no legally defined amount of notes needed to constitute a "substantial part", therefore, for some songs it could be as much as 28 bars and for others as little as five notes.

'In a strict legal sense all sample clearance licences must be obtained before a sample is used. In reality that rarely happens. It's worth noting though that the "price" for obtaining a licence to clear a sample will no doubt be less when the song hasn't been completed, as opposed to when it is climbing up the charts.

'Not clearing a sample that is later recognised by the copyright owner can have dire consequences. The copyright holder can obtain an injunction to restrain a copyright infringement. In real terms that means that all copies of the song must be withdrawn and destroyed, the artist could also be sued for damages for the copyright infringement. Not the thing an artist wants to do after all the expense and work required surrounding a release. If an artist uses uncleared samples they will always be at a disadvantage.

'Parody or soundalike is where someone deliberately sets out to imitate another piece of music. A parody is allowed if it merely conjures up the idea of the original but if a substantial part of the original piece is used then this could be an infringement of copyright. It's worth remembering here that there are separate copyrights in the lyrics and music of a song so just changing the lyrics does not create a whole new song.'

So, assuming an artist definitely wants to use a sample of someone else's work in there material, is there a simple way in which they can get clearance?

'Yes, Dean Marsh & Co. offers a sample clearing service. If an artist provides a copy of their new work in whole, a copy of the work sampled in whole and a copy of the sample. From there for a fee our office will contact the copyright holder and make arrangements to secure a licence for the sample. In return for a licence the copyright holder might ask for any and possibly all of the following: credit as a songwriter or performer on any release, payment for the usage possibly an advance for the usage, a percentage of the record sales of a song if a performance is used and a payment and or percentage of the publishing royalties.'

By this stage, the mind starts to conjure-up all manner of paranoid imaginings. What, for example, is the position then if you go along to a local pub and play someone else's song? As that is their copyrighted material, aren't there implications there, too?

'Well, an artist is generally able to perform any song they like in a pub without paying the composer of those songs,' Ms. Westwood says. 'Collection of monies for performance and broadcast of songs is done by the Performing Rights Society (PRS) and they deal directly with the venue. Every venue that has live or pre-recorded music must pay a fee to the PRS and PRS collect that fee and administer the process of paying the writer of the music. It isn't an exact science so the particular writer of the song might not be paid for that particular performance but the system is in place for some form of payment. If you are an artist with a published song (i.e. the song has had a commercial release in the UK) then you are eligible for membership to PRS.'

If all this consideration of the ins and outs of copyright has done anything at all to make you realise just how complicated the law relating to our business can be, then it has served a very useful purpose, over and above what it will have told you about copyright. To inject a personal note, I have never quite recovered from being invited some years ago to the home of a musician I'd got to know, only to find that he lived in what was more or less a pre-fab on a council estate. What made the visit particularly poignant was that he had two gold records on the wall and no, in case that's what you are thinking, he hadn't put the proceeds up his nose -. he was just one of the many professional musicians I've met down the years who had been, effectively, swindled out of his earnings by managers, record companies, publishers and promoters. You think I'm exaggerating? I can do no better than point you in the direction of legendary music business manager Simon Napier Bell's deeply worrying paperback Black Vinyl, White Powder (Ebury Press, £7.99) which, besides being by turns chilling, thought-provoking and hilarious, clearly lays out the pitfalls that await the aspiring songwriter or musician.

And the remedy? It's tragically simple. Never, ever, sign anything unless you have retained a lawyer to represent you and when you do, make sure they are experienced in the field - and that is just as true of songwriting deals as it is of record or management contracts. Needless to say, Kate Westwood agrees: 'It is always advisable to seek professional advice before signing anything to do with the sale of your copyright work. Due to the legal language of many contracts it is easy for an artist to misinterpret the meaning of a contract and sign away all their rights in their copyright work, which may not be what they intended to do, or for an unreasonably low sum. A solicitor will be able to advise as to whether or not the terms of the contract in question are reasonable and will be able to advise if a licensing arrangement would be more appropriate.

'It is worth noting that any assignment or sale of copyright must be in writing and most reputable record companies and labels will require an artist to take independent legal advice before signing a contract.'

Kate Westwood can be contacted at Dean Marsh and Co: 020 7553 4400 E-mail: info@deanmarsh.com, Web: www.deanmarsh.com

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