From 1956 onwards unions at the four Unilever factories in Indonesia (three in Jakarta, one in Surabaya) became increasingly active, particularly Serbuni.
Sejak 1956 sampai seterusnya, serikat di empat pabrik Unilever di Indonesia (tiga di Jakarta, satu di Surabaya) menjadi semakin aktif, terutama Serbuni.