There is an image of this cultivar on the Hosta Library. From the photo on the HL website, it appears to be a small size hosta with light green leaves and creamy white marginal variegation. This non-registered cultivar with H. sieboldii in its background was originated in Japan and introduced by Fritz Köhlein of Germany. 

Silver Spoon. There is also a cultivar named H. 'Silver Spoon'.