I started using this product through Birchbox and it has significantly lightened my acne scars! It also seems to have an added effect of pushing out acne, which helps to keep my skin clear. When I stopped using it for ~6 months, my acne came back (I have the kind that is very deep and hangs around for months before leaving a deep red scar). As soon as I started using it again, my skin cleared up and my scars went away quickly. Even my fiance was surprised because it was THAT noticeable. Super awesome.
Just don't forget to wear sunscreen! Makes you more susceptible to burning.