Mittal Steel Company N.V., incorporated in the Netherlands and headquartered in the United Kingdom, was a steel producer. In 2006, it produced 110.5 million tonnes of steel and had annual production capacity of 138 million tons of steel.
As of 2006, the company was 44.79% owned by Lakshmi Mittal and his family and 54.74% of the company was publicly traded.
In 1992, the company acquired Sibalsa from the government of Mexico.
In 1994, the company acquired Sidbec-Dosco.
It also acquired Walzdraht Hochfeld and Stahlwerk Ruhrort.
In 2004, the company acquired Polskie Huty Stali, BH Steel, and certain Macedonian facilities from Balkan Steel.
In 2004, it merged with LNM Holdings and was renamed Mittal Steel.
In 2005, the company acquired International Steel Group.
In August 2006, the company acquired Arcelor in a $33 billion transaction to form ArcelorMittal, which owned 10% of steel capacity worldwide. The merger was consummated after Mittal Steel raised its bid for Arcelor and the Mittal family agreed to relinquish its controlling stake in the company and execute a standstill agreement not to acquire a controlling interest without approval from independent directors.