... largest independent ad technology company.
The deal exemplifies Sir Martin Sorrell's appetite to own technology in addition to providing advertising and marketing services.
Under the terms of the agreement, New York based AppNexus will acquire Xaxis’ premium ad-serving technology Open AdStream (OAS), now known as Xaxis For Publishers.
In addition, WPP will invest $25 million in AppNexus, adding to the $85 million in funding the company recently raised on its valuation of $1.2 billion.
Over the past year AppNexus servers processed 16 billion ad buys daily and was responsible for an estimated $700 million in ad spending in 2012, giving the firm the biggest reach on the open web after Google.
It also offers online auction infrastructure and technology for data management, optimisation, financial clearing and support for directly negotiated advertising campaigns.
Moreover, the system integrates with advertising sources including Google's DoubleClick, Microsoft's AdECN, and aggregators.
It operates out of multiple data centres, including one in Amsterdam serving Europe and the Middle East.
Read the original unabridged FT.com article.