Chicago’s Hindman auction house will merge with the Philadelphia-based firm Freeman’s, the oldest business of its kind in the United States. Through the merger, the two are poised to become the largest mid-tier auction house with a focus on American art. Across the two auction houses, there are six salesrooms and 18 offices, all based in the US. Combined, that surpasses the domestic footprint of larger global auction houses, like Christie’s, Sotheby’s, and Phillips.