Originally Posted by ajonkarl
When one buys a Simplicity, McCalls pattern, it is assumably to make the item, so when I purchase a quilt pattern is it not to make the design? I doubt anyone would use the exact fabric, so it would not be an exact copy. I don't understand what the issue is here, unless someone makes exact replicas and tries to sell them, then it would not be fair to the designer.
That's called a derivative work. If you have access to the original work (like a photo) and a 'reasonable observer' could see your work as 'substantially similar' to the original work, then it's a derivative work and it's copyright infringement. There is no 40% rule, change the color, size, fabric, etc qualifier that makes it okay.