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No, you already have the copyright when you created it.
...(providing you are in the US)...is to send the whole thing at once to the copyright office.
This is not limited to just the US, even though the LOC is in Washington, DC.
I'm in Canada and have 2 works registered there for about 20 years now, which are actual copies of my sheet music of the melodies & chords I painstakingly wrote out by hand - [instrumentals].
Now there are better, faster, easier methods, of course.
I will be submitting more works later this year, although I read that one post about SONGUARD with interest, and will investigate some more.
I do want to mention that although seemingly rare, the cost of going to court to 'prove' that that song is yours can be a staggering $20,000-50,000, AND the onus is on YOU to prove the theft.
One of the stipulations is: You would have to prove that *they* [whoever that is], had access to your works in the first place.
Now that could be tough - real tough!
Short of following them around and outright stalking their every move, [all based on the assumption that they will indeed do that to you some day in the future], it would best to keep records of where & when AND particularly to whom your works were sent.
Even then, there's no guarantee.
The advantage is clearly with the thief - as usual.
Possession is indeed 9/10ths here, at least in cases like these.
The more protection, the better, as a settlement out of court may be more appealing to the other party if you're well armed and your lawyer has lot's of Ammo to fire at them to begin with.
Certainly the costs would be much less to prepare ahead of time with various methods of Copyright Protection - kind of like insurance - you may never need it, but glad to have it when you do.
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Hey - look at my post count!
It's 4:20 here - finally!!