Bundesgerichtshof
Only one year later, Scharen was appointed as judge at the Federal Court of Justice of Germany, where he was assigned to the 10th division (German: "X. Zivilsenat"), of which he was since 2004 the division's deputy. This division mainly handles patent law and public procurement cases. On 1 April 2009 Scharen was finally appointed chairman of this division by the President of Germany, on a proposal of the Presidium of the Federal Court of Justice. On 31 August 2010 he retired.