Combing through the latest edition of Jasper Morris Inside Burgundy, it mentions that the Bourgogne AOP single-vineyard Le Chapître "has since been promoted to AC Marsannay". He also mentions Bourgogne-Clos des Marcs d'Or being a legal single-vineyard that I had never previously come across. Not sure where exactly this vineyard is, if anyone finds it on a map lmk!
Update: it appears that Clos des Marcs d'Or is presently a .41ha plot of Chardonnay right outside of Dijon, owned and farmed as a monopole by Domaine Derey.