Shell plc is a British multinational oil and gas company, headquartered in London, United Kingdom. Shell is a public limited company with a primary listing on the London Stock Exchange and secondary listings on Euronext Amsterdam and the New York Stock Exchange. A core component of Big Oil, Shell is the second largest investor-owned oil and gas company in the world by revenue, and among the world's largest companies out of any industry. Measured by both its own emissions, and the emissions of all the fossil fuels it sells, Shell was the ninth-largest corporate producer of greenhouse gas emissions in the period 1988–2015. Shell was formed in April 1907 through the merger of Royal Dutch Petroleum Company of the Netherlands and The "Shell" Transport and Trading Company of the United Kingdom. The combined company rapidly became the leading competitor of the American Standard Oil and by 1920 Shell was the largest producer of oil in the world. Shell first entered the chemicals industry in 1929. Shell was one of the "Seven Sisters" which dominated the global petroleum industry from the mid-1940s to the mid-1970s. Wikipedia