Ristomatti Ratia (born 1941) is a Finnish designer and son of Armi Ratia, the founder of Marimekko. Ristomatti Ratia has created a wide range of products. Many of these have become familiar classics, such as Olkalauuku, the popular Marimekko shoulder bag, designed in 1970 for Marimekko and the Palaset storage line.