after overtaking Microsoft last year. The etail giant is also the fastest-growing in the sector, with revenues up 30% this year alone. "Amazon's ad business has attracted massive increases in spending

after overtaking Microsoft last year. The etail giant is also the fastest-growing in the sector, with revenues up 30% this year alone. "Amazon's ad business has attracted massive increases in spending

for example Amazon and Microsoft (or indeed IBM) for cloud-infrastructure, and Salesforce.com and Workday for applications. "Already they can see what I would call cloud sprawl," said IBM CEO Gini Rometty,

marginally above Microsoft. It's a bittersweet ending for a company that, at its peak before the dotcom bubble burst in 2000, was worth $125bn. In 2008, Yahoo's board rejected an offer of $44bn from Microsoft.

Apple, Google, Amazon and Microsoft - dominate this ranking, with Apple's lead at the top table rising steadily. At a valuation of $215bn, it is now $60bn clear of second-placed Google. However, Amazon

who include WPP, News Corp, Fidelity, Microsoft and Deutsche Telekom. The deal will allow AT&T to better monetise its significantly expanded digital content platforms, creating what has been described

Prix went to McCann London for a campaign to promote Microsoft's Xbox Design Lab, an ecommerce store where players can buy personally customised controller handsets for their consoles. McCann turned the

Microsoft expanded its presence in the software development sector with the acquisition of coding collaboration site GitHub for $7.5bn in stock. GitHub manages a community of more than 28m developers

rise to just under $301bn. Amazon overtook Microsoft for the #3 spot, but both are still around $100bn behind the two leading brands by valuation, while Facebook was #6 on $162bn. The biggest change among

Microsoft reappointed Dentsu Aegis Network - primarily Carat - as its global media agency. Oil refiner and retailer BP remained under the WPP umbrella. The business is currently led by Ogilvy and Mindshare.