We constantly get this crap at work. Normally they get hold of one name of linked in or something and then call the main switchboard.
The worst we had was recruiting firms calling the switchboard to be transferred through. Then they would claim to be Fedex and try to phish for names. "Oh this package has to be signed for by a member of the engineering team, is there anyone who might cover if you are at lunch when it's delivered" Riiiiight!
You eye it with disgust, but pick it up, and sure enough it's a recruiter sequentially dialling through the extensions. And they have the nerve to pretend they are calling just for you!
She repeated back to me: "Knowledge of debugglers".
1. Announce that someone is applying for a job without first asking them if they're interested. (Yes, this happened to me: I was invited to go somewhere and speak about my research; I agreed; and when I turned up, I was introduced as "Colin Percival, who wants to work for us". To this day I still don't know exactly what job I was "applying" for -- I talked about my research and got out of there as quickly as I could.)
2. Announce that someone is applying for a job other than the one they told you they were applying for. (In fact, there were three different positions involved, and in the end I was offered the position I originally applied for -- but not before having a list of on-site interviewers selected on the basis of a different position and then partially reworked on the spot.)
Poor phone screening technique.
All calls should be routed through one person where they can shield internal people from "unknown" callers. This simple hack works surprisingly well in large companies and is a 101 social engineering technique. Kevin Mitnick now makes a living writing books on this subject ~ http://www.amazon.com/Art-Deception-Controlling-Element-Secu...
I just pickup and immediately hang up.