I am certain that in my case, it was someone at the bank. I refinanced my house with the same bank that held my previous mortgage. When they pulled my credit, my card was compromised a week later. Because of the refi boom, they were slow, and ended up pulling my credit again. 3 days later, card was compromised again. Prior to that, my card was compromised one other time, about 8 years ago. I've had the card for over 20 years.