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Cologne's Rheinauhafen had lost its function as a Rhine port due to the obsolescence of the port facilities and other competing Cologne ports. Therefore, on July 13, 1976, the Cologne City Council decided to convert the port area into a "leisure and recreation facility". This included the refurbishment of some of the old port structures, some of which are listed, as well as the construction of new residential and commercial buildings. The latter category included the buildings designed by Aachen architect Alfons Linster and Hamburg-based architects Bothe, Richter, Teherani (BRT), whose shape (an inverted L) is based on three harbor cranes with outriggers pointing towards the Rhine. In the copyright dispute between the Hamburg architectural office and Linster, the Federal Court of Justice ruled on February 26, 2009[1] that the defendant Alfons Linster is to be regarded as co-author of the Kranhäuser of the "workshop draft" according to § 10 Para. 1 UrhG. The property belonging to Häfen und Güterverkehr Köln was acquired by private investors in November 2006 for the purpose of building the crane houses.