Wikipedia
An Oberlandesgericht (plural – Oberlandesgerichte; OLG, , or in Berlin Kammergericht: KG) is a higher court in Germany.
There are 24 OLGs in Germany. They are positioned above regional courts ( Landgericht) and below the Federal Court of Justice (Bundesgerichtshof), in family and child law above the district courts ( Amtsgericht) and below the Federal Court of Justice. In criminal cases that are under primary jurisdiction of the Federal Court of Justice (i.e., cases concerning the national security), the Oberlandesgerichte act as a branch of the Federal Court of Justice, that is, as "lower federal courts" ("Untere Bundesgerichte").
The OLGs deals with civil and criminal matters. In the Oberlandesgerichte, the offices of the "Generalstaatsanwaltschaft" or general district attorney are located.
The OLG Düsseldorf is one of the most popular patent trial forums for patentees in Europe.
The Oberlandesgerichte were first set up in the German Empire by the Courts Constitution Act of January 27, 1877. In Prussia, there had been Oberlandesgerichte as the higher provincial courts since 1808, known as "Regierung" from 1723 to 1808.