Comment by michaelt

I'm in the UK so I have no Social Security Number, and I still got the HIBP e-mail.

When I looked into it, it turns out the "original" breach is comprised of files named ssn.txt and ssn2.txt which only contains Americans details, and doesn't contain any e-mail addresses.

It seems what happened is there was one leak of US SSNs which the leakers attributed to NPD, then some people bundled that leak up with a bunch of other data (including e-mail addresses and details of non-americans) and who knows if the latter data actually came from NPD?