As of January 1, 2017, you can no longer buy anything at Sotheby’s without proving who you are. I have bought many things from Sotheby’s over the past 30 years. Since January 1, all sales now require a photo ID even if you are paying by check or bank wire. In other words, they want to know who is buying anything tangible to make sure you paid your pound of flesh. This has nothing to do with “cash” transactions; it does not matter how you pay for anything. Just another step forward into the realm of a cashless society for total accountability to the government.
