On: LinkedIn: The Creepiest Social Network

[_hyn3]

Good guess, except neither of us were using Gmail.

[proksoup → _hyn3]

Gmail can be used with non gmail domains.

[_hyn3 → proksoup]

But gmail would show in the Received headers, right..

[chatmasta → _hyn3]

It would show google SMTP server if one received it in the inbox. I think that's always the case. As far as I know gmail cannot be a web client to external SMTP servers.

[proksoup → _hyn3]

Sorry for ignorance, I don't know what received headers are.

Would the same apply if the email you sent is "forwarded" automatically to another email address that you are unaware of?

Or by received headers you meant you get a reply back from the celebrity?

[_hyn3 → proksoup]

> Or by received headers you meant you get a reply back from the celebrity?

Yes, I received several replies back but that was the sole extent of our contact on the Internet or real life.

Received headers show the previous mail servers that the email passed through through on its way to you. There can be many; each server adds another.

See https://www.ietf.org/rfc/rfc2822.txt § 3.6.7, "Trace fields" and Appendix A.4 for an example. (Or, press control-U in some mail clients to see the source of an email you received to see all the headers.)

[proksoup → _hyn3]

Oh ...

My money is that they (the celebrity) viewed you on linkedin, and that is the data linkedin used to make the connection.

That's certainly what I do before replying to strangers, google them and look at things.

[_hyn3 → proksoup]

Good thought! That's quite possible, and he may not have shown up in my "These people viewed your profile" list for various reasons.

[chatmasta → proksoup]

Adding to what jameisonbecker said, obviously every intermediary server can also strip, modify, or add any headers that existed when it received a mail, prior to forwarding it.