Microsoft, Yahoo and AOL have formed an alliance to rival Google and Facebook’s growing domination in the online ad display business.

The joint venture will give all three companies the freedom to sell each others’ excess premium advertising inventory to their own customers with the aim of increasing sales and catching up with their rivals.

According to figures produced by online research firm eMarketer, Facebook has dominated the US display market this year with a 17.7 per cent share of the total advertising spend by clients, while Google accounts for 9.3 per cent.

In press release issued by Microsoft, the Redmond giant says that the partnership will “offer the efficiency of buying premium display inventory at scale to reach customers and audiences.”

You can read the official press release in full here.