However, before these plans could materialize, a historic takeover battle lasting several months ended with the acquisition of Mannesmann by the British mobile phone company Vodafone in 2000. On 4 February 2000 Mannesmann's supervisory board eventually agreed to a takeover price of 190 billion €, which was the largest takeover price ever paid until that date and still is the highest. The telecommunications division of Mannesmann was subsequently incorporated into the Vodafone Group. The other divisions were resold to various companies soon after the deal. The origins of Mannesmann, the pipe production activities of Mannesmannröhren-Werke AG, were sold to Salzgitter AG along with the brand name Mannesmann. During the Second World War, when the company was chaired by nazi party activist Wilhelm Zangen, slave labour was employed at their tube rolling mills. Zangen served four months in prison for his involvement, although he remained a leading figure with Mannesmann until his retirement in 1966. In 2000, Mannesmann was acquired by Vodafone Group Plc. in a tax-free exchange of 53.7 Vodafone shares for each share of Mannesmann. This was a controversial takeover, since never before in Germany had a company as large and successful as Mannesmann been acquired in a hostile takeover by a non-German owner. The merger was said to have been engineered in a private deal concluded between Mannesmann's management and Vodafone. The acquisition was spearheaded by Vodafone's Chief Executive, Chris Gent, and Goldman Sachs' Scott Mead, who was then the chief advisor on the deal. The circumstances of the deal and the (not only for German standards) particularly high severance payments awarded to leading managers of the company led in 2004 to a trial at Landgericht Düsseldorf (Düsseldorf Regional Court) - the so-called Mannesmann trial. The accused, among others the chairman of the supervisory board at the time of the takeover, Josef Ackermann, and the former CEO of Mannesmann, Klaus Esser, were initially granted a full discharge by the court. However, after revision proceedings, the Bundesgerichtshof Federal Court of Justice overruled the contested judgment and referred the case back for retrial at the Landgericht. On 29 November 2006, the proceedings were terminated, with the defendants agreeing to settlements amounting to millions of euros. Under the terms of the takeover deal, Mannesmann sought assurances from Vodafone that the Mannesmann brand and name would be kept under the new owners.