The 30 biggest media companies in the world

Time Inc. used to be the magazine division of Time Warner, but was spun out as a standalone company in June 2014.

Its most well-known titles include Sports Illustrated, Time Magazine, and InStyle.

ZenithOptimedia notes that Time generates the majority of its revenues (53% in 2015) through advertising and that it has suffered from the overall decline in magazine circulations. "Time Inc.'s revenues declined at an average rate of 4.1% a year between 2011 and 2015."

This Japanese media group owns the eponymous daily newspaper, The Yomiuri Shimbun, which is the most popular daily newspaper in the world, with a circulation of more than 9 million copies.

The company also owns English language daily The Japan News and it owns a 14.6% stake in the Nippon TV network, publishing group Chukoron-Shinsha, and Japanese professional baseball team the Yomiuri Giants.

ProSiebenSat.1 owns 15 TV stations across Germany, Austria, and Switzerland, reaching around 42 million households in total.

The company is currently working to grow its "digital and adjacent" business, which accounted for 26% of total revenue in 2015.

Gannett owns 93 daily newspapers in the US, including USA Today, and 400 other non-daily publications. It also owns more than 150 properties in the UK, within its Newsquest unit.

ZenithOptimedia predicts the company, which had almost $200 million in cash at the end of 2015, has capacity for growth through acquisitions.

2015 was an acquisitive year for Gannet: It bought Romanes Media Group, the 59.4% it didn't already own of Texas-New Mexico Newspapers Partnership, and Journal Media Group.

Hubert Burda Media is a Germany-based publisher that owns 93 magazines in its home country and 320 international titles.

Its well-known brands include the German editions of Playboy, Elle, and Harper's Bazaar, and Burda Style.

Fuji Media Holdings is one of Japan's biggest media owners.

It operates the Fuji Television Network and radio business Nippon Broadcasting System.

The company's total media revenue took a slight dip on the $3.274 billion ZenithOptimedia estimated for 2014.

ITV is the UK's largest commercial television network, with more than 15 channels.

It also has stakes in digital TV services Freesat (50%) and YouView (14.3%) and it owns 40% of news production company ITN.

Mediaset is the largest commercial broadcaster in Italy and it also owns a controlling stake in the largest TV network in Spain, MEC.

The company's Italian channels include Canale 5, Italia 1, Rete 4, Boing, and Cartoonito.

Mediaset was founded in the 1970s by former Italian Prime Minister Silvio Berlusconi. His son Pier is vice-chairman and his family-owned Fininvest still has a 41% stake in the company.

Germany-based Axel Springer owns newspapers, magazines, TV channels, radio stations, and websites in 35 countries.

Its biggest titles in Germany include the daily newspapers B.Z., Bild, and Die Welt.

In September last year, Axel Springer acquired 88% of Business Insider for $343 million in cash, bringing its total stake up to 97%.

France-based JCDecaux is the largest outdoor advertising company in the world, with more than 1 million advertising panels and more than half a million "street furniture" panels (think bus-shelters and bike racks.)

JCDecaux made a number of acquisitions in 2015: buying 70% of Continental Outdoor Media, 70% of Eye Catcher Media, and all of CEMUSA.

Hearst publishes 15 daily newspapers, 21 consumer magazines, and 30 TV stations in the US.

Its big brands include the affiliate partners of the ABC and NBC networks, Cosmopolitan, Esquire, and the San Francisco Chronicle.

It also owns around 300 newspaper and magazine titles internationally.

China Central Television is the Chinese state broadcaster.

It broadcasts 21 free-to-air channels, 19 pay-TV channels, and 10 international channels in the English, French, Spanish, Russian, Korean, and Arabic languages.

ZenithOptimedia notes that CCTV didn't publish the revenues raised by the annual auction of its prime-time slots in the autumn, "causing some to speculate it had been overtaken in ad revenue by Baidu, and didn't want to openly admit as much."

Asahi Shimbun is Japan's second most-popular newspaper.

The company also owns 25 magazine titles — including AERA, Sesame, and Autocar Japan — and has a 24.83% stake in TV Asahi.

Advertising makes up around 5% of Microsoft's total revenue, according to ZenithOptimedia.

Microsoft sells ads alongside it MSN portal, search engine bing, video calling service Skype, and its Xbox Live gaming and media platform.

ZenithOptimedia notes that Microsoft increased its ad revenue by an average of 12.5% per year between 2010 and 2015, although this was behind the 17.9% internet ad market growth rate.

Last year, Microsoft announced a big ad deal with AOL, which has seen it supplying AOL's search results, while AOL will handle Microsoft's display ad sales in its top nine markets. Ad tech company AppNexus picked up responsibility for ad sales in Microsoft's other display ad markets.

Time Warner dropped down ZenithOptimedia's rankings from 8th place last year due to hiving off the Time Inc. publishing division in June 2014.

The company now has three operating divisions: Turner Broadcasting System, HBO, and Warner Bros. Entertainment.

Search advertising was Yahoo's biggest earner in 2015, generating 42% of the company's total revenue. Yahoo is the default search option in popular web browser Firefox.

Display advertising is Yahoo's next biggest earner, with the majority of revenue coming from its own sites and 18% coming from third-party affiliate sites.

Some 36% of Yahoo's revenues come from mobile.

The company is currently assessing bids for its core business, which also includes search and mail.

Grupo Globo, Brazil's biggest media owner, was the third fastest-growing company in ZenithOptimedia's rankings, growing media revenue by 15% year-on-year.

The company owns teh newspaper O Globo, 12 magazines, four radio networks, and public TV network TV Globo.

TV Globo held exclusive rights to all 64 matches in the FIFA World Cup in 2014, boosting its revenue that year. It is expected to receive another advertising windfall during this summer's Olympics.

Discovery owns 14 TV networks in the US including the eponymous Discovery Channel as well as TLC and Animal Planet.

It distributes 48 international brands which, combined, reach more than 2.6 billion subscribers in more than 220 countries worldwide.

The US networks still generate almost half of the company's revenue (48% in 2014) and 67% of its operating profit.

iHeartMedia used to be known as Clear Channel Communications and operates a US radio business and an international outdoor advertising business.

The company owns 861 stations in the US, reaching 110 million listeners each week.

It operates 107,000 display advertising structures in North America and 540,000 display units across Asia, Australia, and Europe.

Advance Publications owns the Conde´ Nast Publications magazines business (including titles such as Glamour, Vogue, Vanity Fair, and GQ), several US newspapers (such as The Plain Dealer and The Times-Picayune), and a 31% stake in Discovery Communications.

ZenithOptimedia notes that detailed financial information is scarce, so the above number is an estimate.

News Corp, in its current form, came about after the former News Corporation split its information and publishing business and its broadcasting and film business (21st Century Fox) into two in 2013.

News Corp owns The Wall Street Journal and The New York Post in the US and The Times and the Sun in the UK.

It also owns the promotions company News America Marketing, Barron's magazine, and book publisher HarperCollins.

Baidu is the Chinese language search giant, which also offers maps, social networking, security, entertainment, ecommerce, and mobile services.

It generates 96% of its revenue from advertising.

Baidu rose from 14th to 9th place in this year's ranking.

CBS derives most of its revenue from its TV channels and radio stations.

The CBS Television Network broadcasts to more than 200 affiliated stations, which are home to hits like "NCIS" and "Big Bang Theory."

CBS also has a 50% stake in The CW Network and it has a joint venture with AMC Networks to run international channels like Horror Channel and CBS Drama in the UK, Ireland, the Middle East, and Africa.

CBS also owns 117 US radio stations.

Viacom runs more than 250 TV channels worldwide, including MTV, Nickelodeon, Comedy Central, and Channel 5 in the UK.

As Reuters noted, Viacom shares have fallen by more than 50% in the past two years as its cable networks suffered continued ratings declines. Viacom's US ad revenue has declined in the last seven straight quarters.

93-year-old media mogul Sumner Redstone's trust owns 80% of movie theater company National Amusements, which owns 80% of the voting rights in both Viacom and CBS. Redstone recently removed Viacom CEO Philippe Dauman and Viacom board member George Abrams from the seven-person trust that will determine the fate of the company in the event of his incapacitation or death, Reuters reported.

Bertelsmann owns TV and radio group RTL (a 75.1% stake), book publishing companies Random House and Penguin, magazine publishing company Gruner + Jahr, music company BMG, marketing company Arvato, The Bertelsmann Education Group, and Bertelsmann Investments.

ZenithOptimedia notes that the company's revenues grew 2.8% in the year to December, driven partly by good performances at its German TV business and solid digital growth.

ZenithOptimedia names Facebook as "the main beneficiary" of the transition to mobile.

Its total media revenue grew 63% over the pat year, thanks to the company embracing mobile technology, encouraging users to visit the site/app multiple times each day.

The fourth quarter of 2013 was the first in which Facebook's mobile revenue exceeded desktop and, by the end of 2015, mobile ad revenue accounted for 73% of the total.

21st Century Fox owns the huge Fox Broadcasting and Fox Sports television companies, plus STAR India, and it has a 39% stake in British broadcasting company Sky.

The company's canble network programming division increased revenues by 12.2% in 2015 to a record $13.8 billion.

ZenithOptimedia does not include revenues from Fox's filmed entertainment or direct broadcast statellite television segments in its estimate.

The majority (88%) of Comcast's media revenue came from its NBCUniversal cable networks and broadcast TV divisions.

The cable division comprises 15 national cable networks in the US — USA Network, Syfy, CNBC, and more — and nine international TV channels.

On the broadcast side, the company operates NBC and Spanish-language network Telemundo.

The rest of Comcast's media revenue comes from its cable business, which gets an allocation of ad slots within the cable networks it transmits to customers.

Comcast also owns video streaming service Hulu.

ZenithOptimedia includes only Disney's media networks and interactive divisions for the purposes of its report.

Media networks covers ad revenue associated by its TV shows and the affiliate fees it receives for them, while interactive looks at online properties such as its Club Penguin game and the Disney Infinity series.

The Disney Channel is perhaps the best-known of Disney's TV properties, but it also owns US national TV network ABC, which broadcasts shows suchu as "Modern Family" and "Grey's Anatomy."

Disney also owns a 50% stake in digital media company Fusion and it has a 33% stake in video streaming platform Hulu.

Alphabet is the new holding company that owns Google — and it dominates this ranking by a considerable distance.

Eric Schmidt, Alphabet's executive chairman, recently said that advertising will always be Google's dominant business.

Google makes most of its money through search advertising, but it is also a huge player in display advertising through its DoubleClick ad tech platform, and video advertising, through YouTube.

Google increased its operating profit by 17.4% to $19.4 billion in 2015.