[aflag]

They should be able to explain why so many people received the email though. Was there a fault in the notification system or not? Are they going to send messages to the individuals which received the notification in error?

I get that direct evidence of a leak is difficult. However, a sudden surge of master passwords being known by third parties in uncorrelated accounts is a very good evidence that something happened. If that's not what happened, then what happened exactly? Was it really a bug in the notification system? Do they have evidence that the password used in the blocked login attempts weren't really the actual master password?

There is a lot of things they can do to show they are on top of things.

[tragictrash]

combine that with lastpass' history of security mistakes, the people in on hn claiming that they didn't reuse the master password, and the press releases gas lighting their users, I'm not buying their story for a second.