Another thought is that padmapper is not /copying/ the data - They are summarizing it. So there could be a entire listing for a SF apartment with lots of detai

Another thought is that padmapper is not /copying/ the data - They are summarizing it. So there could be a entire listing for a SF apartment with lots of details and padmapper would not copy any of it- instead they would just make notes - 3 bedroom, location, price, pictures and then link back to CL if someone clicks the listing on PM