jm, what you are experiencing is the IRS's anti-fraud filters in action! I was at a seminar last week where the IRS liaison told us the IRS had 10 filters in place just a few years ago; now they have 140. Hmmm....here's a taxpayer who hasn't filed in years and suddenly surfaces with a K-1 (that won't be in the system for months) and wants a big refund. Or it could be that someone who knows she doesn't normally have to file has been filing using her identity. That someone got hung up in the filters this year, and now the agency wants to identify the real taxpayer. Or maybe she does file but her income is so aberrant this year that the return was hung up by a filter. We've had lots of clients get letters this year asking to see their information documents (the same standard letter your client got). Some were understandable--they changed addresses, banks, names. Others seemed to have no reason except that just maybe a bogus return had been filed using their identity and the filters put it in limbo, waiting for the real taxpayer to come forth.