copyright

A former mid-level editor of a newspaper told me that when a paper publishes a writer's material, the paper obtains the copyrights to that material. He asserted that this was true even when the writer was not paid for the submission, when no written agreement was made, and when the issue of copyrights was not even discussed. I was shocked. Is there some legal presumption that covers this?

I think he is right. Most submission policies say that letters to the editor become the property of the paper -- otherwise they could not publish them -- you send it to them for the purpose of publication, right?