You can’t walk away from a winning bid. That’s Sotheby’s message to a New York art collector who allegedly refused to honor his $6.5 million offer for an untitled 1982 Keith Haring painting, a record price for the beloved American pop artist. The auction house sued Anatole Shagalov in August for $2.13 million — the difference between his winning bid at the May 2017 auction and the price Sotheby’s got for the work after it was forced to resell it…READ MORE