The Gazprom Group is ranked first in the annual S&P Global Platts Top 250 Global Energy Company Rankings.
Company rankings are calculated based on a number of financial indicators, such as asset worth, revenues, profits, and return on invested capital.
The first edition of the Top 250 Global Energy Company Rankings was published in 2002.
S&P Global Platts is an information agency specializing in news, commentary, fundamental market data and analysis, as well as publishing benchmark prices for the commodities and energy markets.
source: http://www.gazprom.com/press/news/2017/september/article364501/?from=mail