Originally Posted by FubsyMog

Not sure if this is any help, but I used was taught (art) by someone who had previously worked in the fashion industry. She said that regarding clothing sold in major stores that was a 'copy' of a catwalk design, the general rule was that 'five small things' had to be changed from the original garment. This way, it was not considered a 'copy', even though they looked extremely similar - the alterations could be as tiny as putting different buttons on, or a different stitch along a pocket.