Allegations against "specific individuals" were investigated by the NSW gaming regulator as part of its probity review of billionaire James Packer's application for a casino licence at Barangaroo.

The Independent Liquor and Gaming Authority says it examined the allegations and found there was "no cause for concern".

Investigation: James Packer. Credit:Sahlan Hayes

But it is refusing to disclose how many people were investigated or any detail about the claims against them.

On Tuesday the authority announced Mr Packer's company Crown Sydney had been granted a 99-year "restricted gaming licence" at his planned $1.3 billion resort at the Barangaroo harbourside development site, which will include a six-star hotel and luxury apartments.