Yahoo on Wednesday said it has agreed to acquire Tensa Kft., more commonly known as IndexTools, a maker of Web analytics software for online marketing. Financial details were not disclosed.

Yahoo expects to complete the transaction by the end of June. In addition to getting IndexTools' analytics business and technology, Yahoo also acquires Tensa's research and development subsidiary.

Yahoo expects the purchase to expand its set of services offered to advertisers to manage their marketing efforts on Yahoo's ad network. IndexTools will add more insight and metrics for online campaigns of the more than 150,000 small to medium-sized businesses marketing through Yahoo, the portal said. Besides analytics, IndexTools also offers bid-management software.

Throughout the year following the acquisition, Yahoo plans to use IndexTools technology to add capabilities that enable third-party developers to monitor and optimize their applications' traffic performance.

On Monday, Yahoo said it would introduce a new advertising management platform called AMP later this year. The platform aims to provide marketers with a single interface to buy search, display, local, mobile, and video ads across Yahoo's properties; Yahoo's premium ad partners, such as AT&T, eBay, and Viacom; and the sites of more than 600 publishers in the Newspaper Consortium. The latter is an alliance of newspapers that sells online classified ads across members' sites. Founders include Belo, Hearst, Lee, MediaNews Group, and Scripps.

Yahoo's AMP platform is scheduled to be available to the consortium in the third quarter of the year and to Yahoo's other advertising partners after that. Yahoo's last major ad system upgrade, its "Panama" search marketing ranking system, was plagued by delays.

Yahoo is currently battling threats by Microsoft of a hostile takeover attempt if the portal refuses its $44.6 billion acquisition offer.