Their data can also be seriously flawed. When I went to apply for a mortgage a few years ago I was nearly rejected because "The Work Number" told my lender that I worked at Arby's and made $11.75 / hour. I've never worked for Arby's and my name is pretty unique (so I don't think it was a duplicate name issue). In any case I searched all 4 other people in the U.S. who share my name, and none of them had worked at Arby's either to the best of my knowledge.
I had to call Equifax, spent 1.5 hours on the phone with multiple confused reps until I found someone who could change my record. I thought there would be some kind of validation process, but nope they just asked me where I worked and how much I made.
It is such a broken system. I'm dumbfounded that Equifax hasn't been sued out of existence.