In Croatia, Prtenjak families are Croats (from Klanjec area ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Klanjec area.
Prevalence
About 20 people with faimily name Prtenjak live in Croatia today, in 7 households. There were 20 of them in the middle of the past century, and their number remains constant. They are located in only five naselja i to in Zagreb (<10), in Zagorska Sela (<10) and Plavic (<5) in Klanjec area, Resnik (<5), and in Sudjuradj (<5).
Outside Croatia
Family name Prtenjak is present in 7 countries on three continents. The family name "Prtenjak " is used by small number of people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.