There is a good article in the Sep/Oct McCall's Quilting mag about copyrights. I sell some of my patterns to quilt stores.....some in Canada......one of the stores wrote me about seeing a lady......copying one of my patterns and teaching it....when asked she said the designer wasn't selling anymore.........I think if you use a design while making a quilt, one should really give the Original designer credit......even if you just say that it was adapted from the pattern.......When you consider the work that goes into developing a new design and then working out the measurements, etc...and the printing, etc...I think it only a nice consideration to give that person credit.