In 1937 the crown signature had an addition. Three numbers was sometimes used to communicate the date of production. The first two numbers indicated the year of production and the third one what part of that very year the production was carried out. During the 1940s another addition to the signature is made, Sverige, and from 1951 it´s translated to Sweden.
In the 1960s another type of signature appears on porcelain, VDN. It´s a sort of quality sign that tells us what kind of material the objects are made of and also what kind of qualities they have. The signature always contains a letter, either B=bone china, F=flintware, P=porcelain or S=stoneware. The numbers 555 as in the picture means that there is no risk for the glazing to crack, that the porcelain can stand all types of food and that it can be used in a dishwasher at 75 degrees Celsius.