This is a number you may see if you get a call from the Vanguard Group Unclaimed Property Unit. If you call this number back, you will get a Vanguard Group message that instructs you that you can reach them at 800-572-3524. I know this is a legit number because they replied to me using this number in response to a voicemail I left them at their 800 number.
However, to emphasize the obvious - If you need to contact the Vanguard Group Unclaimed Property Unit, you should go to the Vanguard Group website and get the number there (i.e., don't call numbers you read on message boards).
We got a voice mail from Elise who said she was with Vanguard Retail Services. She said the call was on a time sensitive matter and to call back at 1-800-823-7413. She left a reference #. When we called, the person said Vanguard when he answered but had no idea why we were calling. We had a recent transaction with Vanguard and didn't think anything about calling this number. After we did it, then I had misgivings. They did ask for a social security number on the call. Of course, today is late Saturday so I will worry until I can contact Vanguard on Monday.
Scam!! Said he was from vanguard but absolutely no way.... I've had multiple interactions with vanguard and none of the phone calls sounded like this, and no one ever asked for my security info over the phone or said it was a "time-sensitive matter." Also when I mentioned this to the caller and refused to give info, he said he would email me about the matter -- which he never did.