Taxability of cost petroleum: cost petroleum is not consideration for service to government and thus not taxable per se. The taxability of Cost Petroleum under GST turns on whether the portion of petroleum retained by contractors to recover exploration, development and production expenses constitutes consideration for a service to the Government or to a joint venture; contractors act as licensees carrying out operations at their own risk, and Cost Petroleum is not consideration for services to the Government and is not taxable per se.