in a strictly technical sense, as soon as you print/ something on paper another solid medium (like a painting) or post it on a website - assuming it's your original work - you automatically have the copyrights.
most copyright statements are very vague. "copyright, blah, blah, blah - all rights reserved." in the case of patterns, the author retains control over what you do with the pattern and what you do with whatever you make from the pattern. (I think. I'm not a lawyer.) You'd even have to be careful about entering something made from somebody else's pattern in a quilt show.
let's use mice as examples.
Mice have been around for who-knows how long. They are everywhere. There are bazillions of different species of mice. so, if i want to draw a picture of a my own mouse, or write a story about him, or make a quilt based on himm or write a little book that tells you how to do those things yourself, nobody can tell me i can't - as long as the words are mine and i'm not copying somebody else's drawing or quilt, etc.
Mickey Mouse, on the other hand, is Mickey Mouse. We know who thought him up; who drew him for the first time; who "brought him to life" and made him a part of our lives. The rights to Mickey Mouse are legally and ethically owned and controlled. I can't legally do much - if anything at all - using his image without Disney's permission. I also can't give him a moustache, call him Mikey Mouse and sell him as my own.
The same goes for Jerry, from the Tom and Jerry cartoons. Or Mighty Mouse. Or, my favorite - The Brain - that hillarious mouse who keeps plotting to rule the world.
Do you see the difference?