PubMatic is the world's first service for web publishers that automates and optimizes ad serving decisions. PubMatic simplifies the online publishing business by determining in real time which ad network can best monetize each ad impression for a publisher. PubMatic also simplifies ad network management by giving publishers one set of ad tags and one integrated reporting interface across multiple ad networks.
http://www.pubmatic.com/publishers/PubMaticFAQ.html

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