First, let me reiterate that you do not NEED to file for a copyright to own the copyright for things you have written. You immediately have that copyright the moment you write the content. You don't need to file, to email it to yourself, to mail it to yourself, or anything else. You write it, you own it. The reason you would file for copyright is if you wanted to be able to get extra monetary damages from a thief. I cover thse details in my How Copyright Works page.
So let's say for whatever reason that you do want to file for the copyright, to have that extra layer of protection. Here is how it works for online material.
You Own the Site
I own this site here, LisaShea.com. All content on this site is written by me. At the time of this article that's over 100,000 pages, images, and videos. I have some incentive to protect this work so it's not all stolen by someone.
I have, on my local hard drive, a directory called LisaShea. I start WinZip running, I point it at that directory, and I tell it to make a zip file (i.e. a single massive file) out of all of the various article, image, and video files in that directory structure. In my case it won't fit onto a single DVD. For some people their site might fit onto a DVD.
Next, I fill out the online form at the US copyright website. I then follow their instructions and mail the DVDs into the address given. The US copyright office receives the data, verifies it matches what I say it does, and they give it an ID number. Voila, that set of content is now under "official filed" copyright. That block of data is one work, just like a book is one work. It is a coherent set of information that belongs together.
I'll note here that you should ALWAYS have a full copy of all content you write on your own hard drive. Don't have your content only online. You never know when online sites will be hacked or have hard drive meltdowns or other issues. It happens quite regularly. Keep copies of all your content on your own system. It is your own work you are protecting.
You Do Not Own the Site
What if you're writing for a third party website? The main question here is if, when you wrote the content, you turned over your rights to someone else. Let's say you wrote a series of articles on financial news for a website, FinancialNewsAreUs.com. You signed a contract with them saying they would give you a bio mention and in return you handed over full rights of that content to them. They now own it. They now hold the copyright. You do NOT own it any more. You do NOT hold the copyright. So you cannot copyright it.
However, in most cases when you post something to a website you are only giving them permission to print your words. You are not giving them your full copyright. You still hold the copyright. This means you can still file for the copyright on it and protect your efforts.
Again, as with the "your own site" example above, you should have copies of all your content on your local hard drive. So in the financial news example I would probably have a directory on my hard drive called /financialnews/. I would point WinZip at that directory and zip up all the articles in that directory. I would put that ZIP file onto a DVD. I could then submit that DVD to be under copyright.
It's fine that your content was shown on a website. It's fine that you don't own that website. All that matters is that you wrote the content and that you are the copyright holder of the content. You can now file for a full copyright protection on it.
I'll note here that it's important that you copyright what YOU wrote. If the site you posted on has graphics or other text around your article, make sure not to include any of that. The only thing you should submit to the copyright office is your actual words you yourself wrote. This is why it's best to keep a copy of the actual article on your hard drive. That way it's nice and clear that you are submitting just the article you wrote, and nothing else.
Let's say you file a copyright of all your website content for your site WineIntro in 2010. Now it's 2017 and you've made a ton of changes to the site. You've updated many of the articles and added many more. Now what do you do?
There's no way in the copyright world to "change" a copyright. Copyright doesn't have a notion of "change". So what you can do is submit a new version. This would be as if you had a first edition of Dieting for Dummies and were now submitting Version 2 of Dieting for Dummies. It's a fresh, new version with a fresh, new copyright. So the same holds true here. I would do a fresh, new filing of my copyright for WineIntro 2017. Just like the first time, I would zip up the entire directory and submit it. That way it includes all the new files, all the changed files, and everything. It's nice and clear that the entire set of data as of 2017 is fully covered.
Of course, it's always best to talk with a lawyer about your own particular situation with copyright, for full protection. I am not a lawyer :). Also, this is how it works in the US. If you're in another country they probably have a similar process.
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