Media corporations have bigger budgets than some nation states. As agents and moderators of globalization they have economic and opinion-shaping power. They deal with the contemporary challenge of combining business segments belonging to the "Old Economy" with those of the "New Economy" by restructuring measures, cooperation or mergers with advertising agencies or social media platforms. It is technological progress and growing competition that force media corporations to expand their businesses on a national as well as an international level. To successfully compete, some media companies establish partnerships with financial investors, which in some cases have garnered considerable influence.

Who controls big media corporations? What kind of strategies do they apply?  What is the role of private equity investors? Based on the 2005 book "Who controls the Media" by Lutz Hachmeister and Günther Rager, the Institute of Media and Communication Policy established the media data base mediadb.eu in order to provide comprehensive and up-to-date structural data concerning international media corporations.

The annual ranking of the 50 world's biggest media corporations includes companies that have a strategic focus on the creation of content for print, television, film and online properties. Because some cable companies control the distribution of programming and produce content themselves, they are included in the ranking as well. Listed are parent companies (such as News Corp.) even if a subsidiary (e.g. BsykB) generates revenues that are higher than other parent companies. The size of a media corporation is based on the media revenues generated in the past financial year. All amounts of revenue are converted to Euros, applying the annual average exchange rates.