Microsoft has acquired London-based map provider Multimap in a deal that adds fuel to an already white-hot sector.

Terms of the deal, announced Wednesday, were not disclosed, but the web site of The Times of London reported that Microsoft paid about $50 million.

Twelve-year-old Multimap, whose web site attracts more than 10 million unique visitors, began seeking new investors for a capital restructuring about nine months ago when Microsoft came calling.

"Rather than taking a partial stake, they were interested in a complete takeout," Chief Executive Jeffrey Kelisky said.

Since its founding, the company had received one substantial outside investment worth about 1.9 million British pounds, or $3 million, from TV production company Flextech in 1999. Flextech later was renamed Virgin Media Television after a series of acquisitions.

Microsoft is locked in a race with Google to roll out location-based services designed to make advertisements more relevant to users of mobile devices. To date, Google Maps and Google Earth have enjoyed strong leads over their Microsoft equivalents.

In November, Google launched a new version of Google Maps for mobile that uses cell tower information to locate users and help direct them to their destinations.

In a statement, Microsoft said Multimap could be integrated with its current Virtual Earth and Live Search services as well as its aQuantive advertising unit.

In addition to providing consumer mapping and direction services, Multimap provides business-to-business services such as store finder and travel directions to Superdrug Stores and Ford dealers.

Earlier this month, shareholders of TomTom, a maker of navigation devices, voted in favor of acquiring Tele Atlas, a Dutch mapping company, for about $4.3 billion. That vote came after TomTom outbid rival Garmin. In October, No. 1 mobile phone manufacturer Nokia bought digital mapmaker Navteq for $8.1 billion.

Mr. Kelisky said the market for mapping companies got progressively steamier during the company's quest for fresh capital.

"During the process, more and more heat was being generated in the mapping space," he said.

Unlike the Navteq and Tele Atlas, Multimap does not develop its own mapping data. Instead, the 120-person company licenses the data from providers like those.

Mr. Kelisky said business customers like Caterpillar and Hertz generate about two-thirds of revenue, while consumers count for the remainder.