AppNexus has been valued at over $1.2 billion

Ad tech company AppNexus continues to roll up financing, announcing today new funding of $60 million. In a post today on the company’s blog, CEO and co-founder Brian O’Kelley said his company is pursuing its “White Whale” of “making the Internet better by making advertising better.” The New York City-based company, which bills itself as “the world’s largest independent advertising technology company,” now has a valuation of $1.2 billion. The new funding comes on top of $75 million raised last January in its fourth round. Not counting the potential $40 million in additional funding, the company has scooped up slightly more than $200 million since its founding in 2007, from such investors as Microsoft and Technology Crossover Ventures.