According 6 § 4 Chapter. ABL you can take in one subject in the statutes of a share of a particular type under specified conditions and in unspecified ways should be converted into one share of other specified types (omvandlingsförbehåll).
For example, you can take on a subject that B-shares 3 years shall be converted into Class A shares.
When a stock is converted, this shall be immediately notified for registration in the companies register. A transformation is effected when it is registered in the companies register and entered in the share register or, if the company is the record companies, in avstämningsregistret.