In theory, the internet offers brands the opportunity to target and deliver a message to nearly any audience in the world. In practice, doing so accurately and efficiently is often far more difficult that it would seem from the outside. Under the radar startup Traackr offers an enterprise-grade people discovery engine to help brands execute effective influencer marketing initiatives.

Although named like an testosterone-laced action movie, the four-year-old company has proven its ability to identify, rank, and monitor people online based on the content they produce and the conversations they influence, attracting more than 140 paying enterprise clients including top digital marketing agencies and Fortune 500 brands.

Today the company is announcing $1.5 million in new funding from several angel investors including serial entrepreneur, Viant co-founder, and Traackr Chairman Robbie Vann-Adibé, as well as multiple unnamed early Google employees. The company was bootstrapped early on from its 2008 launch in Cambridge, Massachusetts until moving to San Francisco in 2011 when it raised a its previous $1 million seed round from Boston-based Launch Capital and Tollman Capital Partners, as well as angels Vann-Adibé, Christopher Muenchhoff, Zev Laderman, and Qamar Aziz.

Unlike Klout, Kred, and others, Traackr is not a vanity social game. The company has created true people search technology, which indexes the Web by “author” to find the most relevant people on any given topic. Brands run custom searches for influencers capable of both amplifying their message and delivering strategic insights. Beyond a ranked list of top influencers, Traackr users can drill down into individual profiles to view recently published content, historical content performance data, and social media metrics.

“When we first set out to build Traackr, our goal was to completely rethink search and focus it on people rather than Web pages in order to discover the people and content most relevant to any given Web search,” says co-founder and CEO Pierre-Loic Assayag.

While the natural comparison is to Klout, the similarities between the two companies are only surface level. Yes, both talk about online influencers, but Traackr is far more focused on expertise and relevancy, while Klout is more of a social pagerank that measures audience size. Customers pay Traackr for the quality of its search results, a category in which they’re most certainly not competing against Klout.

While it might seem at first glance like Traackr is creepy or invading online privacy, its product focuses on public conversations on subjects where individuals – often academics and professional bloggers – are typically looking to develop authority for professional reasons.

The service then just recognizes and points out their influence to brands looking to deliver messaging around that subject. An ad agency, for example, can see who should be targeted with a particular social media campaign or who it should approach for a product review.

Traackr offers its product on a subscription basis, proving that paid search is in fact a viable model. Current customers include Cisco, SAP, JP Morgan, Charles Schwab, Raytheon, Paramount, and Honda, as well as one out of two leading agencies, according to its CEO.

“We have proven that if a search is powerful enough, delivers enough value, and saves enough time, organizations and individuals are prepared to pay directly for a search – and that advertising revenue is not the only model for a search engine,” says Vann-Adibé

The company has been deliberately quiet and under the radar, but with the feeling that the market has matured quite a bit, it’s now stepping on the gas to gain market and mindshare, according to Assayag. The newly raised funds will be used to bolster its technology team and explore new product offerings and markets.

Like consumers, enterprises are always looking for methods of cutting through the online noise to receive a targeted and useful signal. People search is sure to become more valuable in this process and Traackr has proven its ability to deliver among the best results in the business.