Due to competition from other Prague breweries, the brand name Staropramen, which translates as “old spring" (water source), was registered in 1911. After the First World War, all three breweries saw a period of sustained growth, and by the 1930s Staropramen was the largest brewery in Czechoslovakia. With socialism after the Second World War, all Czechoslovakian breweries were nationalised, including Staropramen. After socialism ended in 1989, the brewery, along with the Braník and Měšťan breweries, became in 1992 part of the Prague Breweries group (Pražské Pivovary), which by 1996 came under control of the Bass company. Bass brought Ostravar into the group in 1997, then in 2000 sold its brewing operations to Interbrew, which merged with AmBev in 2004 to form Inbev. Staropramen has seen steady growth and is currently the Czech Republic's second largest beer producer with a 15.3% share of the domestic market.