I've been seeing this problem for a while on my Cayman Sand Beige seats and it only happens with my wife's jeans. My regular 505' s don't leave any color. I have found that if I wipe the passenger seat with a damp towel it removes most of the color. Fortunately our new 2013 XC 70 has beautiful Espresso Brown leather seats so they don't show the color transfer. I have however noticed that the soft plastic at the out board side of the driver's seat where the seat belt anchors seems to be permanently stained. Not a problem since we are so impressed with the car.