So, a few months ago I was working for a big blog and then I resigned because I didn't want to write any more articles for them. Some of the articles were original and a few were translations by me from other articles. Do I have any claim to ownership if the articles? I had no contract with them governing what I can do with the material I wrote, so would it be possible for me to ask the owner of the blog to take them down? Is there any law on this issue? In case you need to know I live in Greece, and the blog is based in Greece.
There are three questions relevant to this issue:
- Who owned the copyright in the first place?
- Was the copyright transferred?
- If not, was a license given to the site to use the content?
In general, under most countries' laws, the person who creates an original work owns the copyright. The person with the copyright has the right to copy and distribute the work, and the right to prevent others from doing so.
In some cases, such as where a work is created as a "work for hire" by certain employees under certain circumstances, the initial copyright is held by a third party. You will need a lawyer familiar with your jurisdiction and your circumstances to determine if this is the case.
Finally, even if you own the copyright, you can license others to use your content. This may be in an express written document, or it may be an implied license--implied, for instance, by the act of posting it on their blog. The existence and scope of such a license is, again, something that will have to be determined based on your country's specific laws and your specific situation.
The bottom line is: if you submitted articles to that blog, you can't complain that they posted them. Depending on the license in effect, you might be able to get them taken down, or you might not. You need a lawyer, not the internet, to tell you what your rights are in this very specific case.
The World Intellectual Property Organization maintains a comprehensive database of IP laws for pretty much every country. Here is the landing page for Greece. More particularly suited to your needs is the Greece page for copyright laws, which you can find here.
If there really was no agreement about who would own your work you may have a shot at retaining the copyright over your work in terms of how they can distribute it beyond their site, but you may not be able to prevent them from publishing your work on their site. You really should consult with a Greek copyright lawyer. Also, since Greece is a civil law country you may be able to find a law on this topic.