This is one of those cases where there are two hostas with the same name. One is registered and, therefore, the "official" version of H. 'Ming Dynasty' while the other is a non-registered plant and needs to be renamed to avoid further confusion.
 

This cultivar is of unidentified parentage and it was registered by the Russ O'Harra Hosta Society on Russ O'Harra's behalf in 1999. It forms a large size (20 inches high by 46 inches wide), semi-upright mound of shiny green foliage. The leaves are moderately corrugated and a bit unruly. Pale lavender flowers bloom in July.

Hosta Helper will call this plant 'Ming Dynasty' (O'Harra)

According to The Hostapedia by Mark Zilis (2009), "Another lesser-known hosta exists with the name 'Ming Dynasty'. That version, attributed to Curt Hanson, matures as a 12" by 33" mound of wavy, blue-green foliage and blooms in August."

Hosta Helper will call this plant 'Ming Dynasty' (Hanson)