JMBG

Unique Master Citizen Number (Croatian and Bosnian: Jedinstveni matični broj građana, JMBG, Macedonian: Единствен матичен број на граѓанинот, ЕМБГ, Serbian and Montenegrin: Јединствени матични број грађана, ЈМБГ, Jedinstveni matični broj građana, JMBG, Slovene: Enotna matična številka občana, EMŠO) is a unique identification number that was assigned to every citizen of former Yugoslav republics of the SFR Yugoslavia. Today it continues to be used in almost all of the countries that were created after the dissolution of Yugoslavia – Bosnia and Herzegovina, Macedonia, Montenegro, Serbia and Slovenia use it in its original form, while Croatia has switched to a new identification number called the Personal Identification Number (Croatian: Osobni identifikacijski broj, OIB).

The JMBG was introduced on January 8, 1977 and applied to all citizens born before then and alive at the time. All six republics passed a law on the Unique Master Citizen Number.

Although the Republic of Croatia continued to use the JMBG after the independence in 2002 the official name of the number there was changed to Matični broj građana (Master Citizen Number), acronym MBG. Advocates of the right to privacy argued that JMBG was a piece of personally identifiable information that needed to be protected by information privacy law, mostly because it was unique and it included the person's date of birth. When the law to that effect was passed in 2003 it was no longer possible to use JMBG on identity cards, driver's licenses and similar documents. Even though law hid MBG from personal documents, various institutions (e.g. banks, schools, insurance companies ...) continued to demand citizens to give their MBG while signing various contracts, since MBG was natural unique identifier of each citizen. Seeing flaw of hiding MBG, on January 1, 2009 Croatia passed a new law that introduced a different unique identifier called the Personal Identification Number (Croatian: Osobni identifikacijski broj, acronym OIB). The OIB consists of 11 randomly chosen digits and has been assigned to all Croatian citizens, companies registered in Croatia and foreign nationals residing in Croatia. Although the OIB is in use, the MBG law remains in effect, and the MBG number is still issued. It is used for data coordination among government registries. MBG no longer appears on Croatian identity cards since 2003, instead OIB does, since 2013.

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