One of the core elements of long-term Gas Supply Agreements are price review provisions (also called price reopener clauses), which allow parties to review the price of the gas during the life of the agreement. The importance of such clauses lies in the long-term nature of the agreements (often up to 30 years) and the changing nature of the markets. The price is usually defined in a formula and often, particularly in older agreements, linked to the oil price. The par-ties might also agree on a specific source for the oil price to which the gas price will be linked, e.g. Platt’s Oilgram Report, a daily report that covers market changes, market fundamentals and factors driving prices.