Hong Kong ( CNN ) -- Two billionaire brothers who control Asia 's biggest property development company have gone on trial in Hong Kong 's biggest ever corruption case . Sun Hung Kai Properties ( SHKP ) co-chairmen Thomas and Raymond Kwok were among five people charged with a total of eight offenses , including conspiracy to offer advantages to a public servant and misconduct in public office , the Independent Commission Against Corruption ( ICAC ) said in a statement . The two brothers are ranked 86th on the 2014 Forbes list of the world 's richest people . Hong Kong 's former chief secretary Rafael Hui , banker Francis Kwan and Thomas Chan -- responsible for land acquisitions for SHKP -- were the other men charged after one of the biggest anti-graft probes in the banking hub 's history . Hui , previously the city 's No.2 , faces charges related to misconduct in public office , including the acceptance of rent-free apartments and unsecured loans -- he 's the highest-ranking former official to face trial in the city . All five defendants plead `` not guilty '' to each of the charges . The ICAC revealed the offenses took place between 2000 and 2009 as investigators probed land sales overseen by Hui involving SHKP . The case has caused a media frenzy in the city , where real estate is a local obsession . Sun Hung Kai , which helped to build some of the tallest buildings in the city 's celebrated skyline , contributed to the Kwok brothers ' estimated $ 18.3 billion fortune . The brothers , who were arrested in March 2012 , have always protested their innocence . `` I can say that personally I have done nothing wrong . And I can vouch for Mr. Thomas Kwok that he has done nothing wrong either , '' Raymond Kwok said at a news conference on April 2012 , referring to his brother . `` I hope this investigation will clear my name , '' he said at the time . Hong Kong , a special administrative region of China , is considered to be one of the world 's least corrupt territories . According to Transparency International 's 2013 Corruptions Perceptions Index , Hong Kong is the 15th least corrupt territory in the world -- with the United States , by comparison , ranked 19th .
Property tycoons Thomas and Raymond Kwok in court on graft charges . Charges include conspiracy to commit misconduct in public office , furnishing false information . Their company , Sun Hung Kai , built some of the tallest buildings in the city 's celebrated skyline .