DIOKI d.d. was founded
on 17 July 1995 as a merger of INA-OKI d.d. of Zagreb, DINA
d.d. of Omišalj and INA-Naftaplin's Ethylene Production Unit
of Zagreb. OKI - Organic Petrochemical Company was founded
in 1959, and it was the first producer of petrochemicals
and plastics in the country. DINA was established as a joint-venture
of INA and the Dow Chemical Company to be acquired by INA
in the 1980s. INA-Naftaplin's Ethylene Production Unit was
founded in 1982. Until the end of 1996 the Company had been
a member of the INA-Group; then INA transferred it to the
State Agency for Deposit Insurance and Bank Rehabilitation
(DAB). In the process of voucher privatization in 1998, a
51% stake in the company was transferred to privatization
and investment funds (PIFs). Since 29 November 1999 , the
company has been operating under the name DIOKI d.d.
On 1 February 2003, the company separated its
operations on Krk Island to establish two companies, i.e.
Adria procesna industrija dioničko društvo (API) and Kijac
nekretnine d.d. (Kijac).
In October 2004 the company was fully privatized, and DIOKI
Holding AG, headquartered in Switzerland , became the majority
owner. In the privatization process DIOKI acquired Kemikalije
d.o.o. and thus the Zagreb site was fully integrated - from
tank farm areas to final products. In March 2005 API d.d.
took the old name DINA d.d.
In May 2008, DIOKI d.d. acquired Riječki list d.o.o, a majority owner of a publishing company Novi List d.d., Rijeka.
In 2009, DIOKI d.d. founded Dioplin d.d., Zagreb. The basic activities of the company involve trade in gas; gas supply
to a favoured customers; agency in the gas market; representation in the gas market; gas procurement, storage and
distribution; and gas supply.