I got a phone call from this number by someone claiming to be from the "American Census Bureau" (at 8:00 PM on a Sunday. He asked if I had gotten a letter from them (which I didn't). He then told me there were some mandatory questions which I needed to answer. I told him to call back tomorrow. When I got home I googled "American Census Bureau" which doesn't exist. and then the phone number 415-826-4577 which gave me a residential listing for

Robert Kaiser      (415) 826-4577      
201 Elsie St,  San Francisco, CA 94110