Yes I learned that lesson the hard way also. But did let one slip by when the sales person was unrolling the fabric and the end of the bolt had writing in what looked like a felt-tipped marker on the inside. When I was ready to piece the backing and was pressing the fabric it bled through. It took up over a 1/2 yard of the fabric so I came up short. I had already cut most of the yardage and used it in the top so had to resort to another fabric for the backing. SO ALWAYS CHECK THE END-OF-THE-BOLT FOR MARKINGS ON THE INSIDE!