From The Verge:
In the dataset, there’s apparently a lot of information that you might not want floating around the internet — including birthdays, locations, full names, and phone numbers — so it’s disappointing to hear that Facebook doesn’t plan to notify users that might be affected. The company cited two reasons to Reuters as to why it’s not telling users proactively: it says it’s not confident it would know which users would need to be notified, and that users wouldn’t be able to do anything about the data being online.
“Users wouldn’t be able to do anything about the data being online.”
Homeowner: “I’ve been robbed!”
Policeman: “Well, yes, we got a call from your neighbor that your home was being robbed and we did stop by later after the thieves had left and locked your front door for you. But why would we tell you that? Your stuff had already been stolen and there is nothing you can do!”