The ICAC has heard former NSW Labor minister Eddie Obeid's interests in mining licencesÂ were disguised to avoid any hint of corruption.
Commissioner David Ipp is investigating allegations Mr Obeid and his family tried to hide their involvement in mining projects that stood to make them aÂ $100 million profit.
The Obeids are accused of having inside knowledge leaked from the office of former mining minister Ian Macdonald.
Former Obeid family lawyer Sevag Chalabian admitted that a series of companies were set up to hide the Obeid family name being associated with Cascade Coal, which won the tender for Mt Penny in the Bylong Valley.
Mr Ipp was told the family still owns a 9.3 per cent stake in Cascade Coal.
The Independent Commission Against Corruption (ICAC) also heard Cascade Coal directors Richard Poole and John McGuigan had concerns about the Obeid family's association with the company being made public.
It heard the Obeids had secret interests in two companies granted coal licences in 2009.
Another witness,Â Neil Whittaker, the chief executive of River Energy, told the hearing he could not recall much about a letter with a false company letterhead and his signature on it.
Mr Whittaker, a former National Rugby League (NRL) chief executive and former Krispy Kreme executive, was asked if he signed the document.
He eventually admitted that he did.
"I can't recall who asked me to sign it," Mr Whittaker said.
Frustrated with the time Mr Whittaker took to answer questions, the counsel assisting, Geoffrey Watson, at one point snapped at him: "You must have spoken to some human being to get this information." Mr Obeid and Mr Macdonald are yet to give evidence.