RUdolf KOreska, a visionary locksmith, established Ruko in 1930. From the very beginning, he emphasised technical knowledge, development, education and close cooperation with the police, security companies and insurance companies. This concept formed the basis of the company's success.

Ruko rapidly outgrew its framework in Copenhagen and moved to Herlev in 1960 which is still the domicile of Ruko's factory and main office. Already in 1951 Assa, the Swedish lock company, bought Ruko. In 1994 Assa, owned by the Securitas group, merged with the Finnish Abloy Group. This gave Ruko international status as the Danish company in ASSA ABLOY, the leading group in the global security market.