The man who signed off on billions of dollars of insurance policies for collapsed fast-financier Greensill Capital allegedly went outside usual corporate systems to conduct deals, using emails and telephone calls to avoid disclosing some of them internally.

Greg Brereton, the Sydney underwriter who inked agreements at the heart of $7 billion in disputes entangling major insurers including Australia’s IAG, was also allegedly not obliged to register gifts like wine, meals or event tickets.