Relying on an 1848 Illinois Supreme Court case, KAP Holdings sued Mar-Cone Appliance Parts for allegedly breaching an unusual contract — an agreement to form a partnership. Mar-Cone, aka Marcone, and KAP (which operates as PartScription) sell replacement parts for appliances. PartScription alleged that Marcone orally agreed to an affiliation — “PSM” — that would integrate their “e-commerce platforms” based on the provisions of a “term sheet.”“The first line of the term sheet states ‘PartScription and Marcone (PSM) have …