All licences are governed by production sharing contracts (PSCs) of several vintages, with the most recent 2013 PSC covered in this analysis. National oil company, PetroVietnam, has the right to take an equity stake in each contract area; recent contract awards suggest up to 20-50% under a joint operating company structure. Royalty rates and profit sharing splits are based on production rates. Various fees, export duty on crude oil, petroleum income tax and oil surcharge (additional profits tax) are also payable. Bonuses, cost recovery ceilings and profit splits are negotiable. In designated frontier areas, investors can benefit from lower royalty, oil surcharge and petroleum income tax, and higher cost recovery ceilings and profit splits under the 'petroleum investment promotion' scheme.