Dillinger Hütte is a steel producer in Dillingen, in the German Federal State of Saarland, and has a history stretching back more than three hundred years. The plant was originally founded in 1685, and was Germany's first Aktiengesellschaft, or joint stock company (1809). The first continuous-caster for slabs in the world was commissioned in Dillingen in 1962. A further machine, permitting casting of slabs of up to 400 mm in thickness - the thickest produced anywhere in the world at that time - was added, along with other new facilities, in 1998. In 2010, Dillinger Hütte successfully produced the first 450 mm thick slab - another world record. The principal equipment in the rolling mill now takes the form of two four-high stands, of which one is currently the largest in the world, with an effective rolling width of 5.5 m and a rolling pressure of 110 MN.FacilitiesThe Dillinger Hütte group also includes a further rolling mill operated by GTS Industries in Dunkirk . The group's parent company is DHS Holding, which owns 95.28% of the shares in the operating company, AG der Dillinger Hütte. Another 4.72% are held in free float. The company's products are marketed under the Dillinger Hütte GTS trade name.The shares in DHS Holding are owned 33.4% by the international Arcelor Mittal steel group, with 33.75% held by Saarstahl AG and 15.00% by Struktur-Holding-Stahl. Reciprocal part-ownership exists with Saarstahl AG, in which Dillinger Hütte holds 25.10%. Dillinger Hütte also owns 50% of the ROGESA Roheisengesellschaft iron smelting company, whose blast furnaces, located on the Dillinger Hütte plant site, produce inter alia the "hot metal" required for steel production. ROGESA itself also has a stake in the ZKS Zentralkokerei Saar coking-plant operator, the facilities of which also form part of the Dillinger Hütte site.