SAN FRANCISCO, USA: Microsoft Corp said on Tuesday it had agreed to buy Powerset, a start-up that is working on a new class of Web search that relies on insights from linguistics rather than simple keyword strings.

Satya Nadella, senior vice president of Microsoft's Search, Portal, and Advertising business, confirmed the purchase in a statement, following months of rumors that they were in merger talks. Financial terms were not disclosed.

Powerset's technology breaks down the meaning of words into related concepts, freeing users from having to type the exact words they want to find. This emerging approach to Web search, known as semantic search, has fascinated researchers for decades but proved frustratingly difficult to commercialize.

"Powerset has always been a small company with big dreams, with the ultimate goal of changing the way humans interact with computers through language," Powerset product manager Mark Johnson wrote in a company blog post announcing the deal.

The start-up, with several-dozen staff including academic experts in the field of natural language processing, is one of a handful of Web search acquisitions by Microsoft, even as it has been frustrated in its pursuit of Yahoo Inc.

The software giant said in January it was buying Norway's Fast Search and Transfer ASA, a top provider of Web search services used inside businesses, for about $1.2 billion.

But Yahoo, the No. 2 provider of consumer Web search behind Google Inc, rebuffed a $47.5 billion bid and a partial deal to buy Yahoo's search business for more than $9 billion.


WHADDYA MEAN BY THAT?

Powerset technology looks beyond words to try to understand conceptual relationships to get closer to what a user is looking for, analyzing sentences and whole documents to do so.

The San Francisco-based company is one of a number of start-ups seeking to use semantic language software to improve on the current generation of search dominated by Google, Yahoo, Microsoft, and Baidu.com to a lesser degree.

Powerset has mounted public demonstration projects to showcase the power of its approach to search. In May, it began offering a way of searching millions of entries in Wikipedia's online encyclopedia, helping users find detailed answers to questions rather than isolated links requiring more research.

Making it possible to search the wider Web using conversational language is expensive, Johnson said, adding: "Microsoft accelerates our ability to move Powerset to the entire web faster than anyone could have imagined."

Microsoft said Powerset's software, together with similar semantic Web tools developed by Microsoft Research, can help it develop products that understand the intent of a user's word choices in each Web search.

"We know today that roughly a third of searches don't get answered on the first search and first click," Nadella said. "Usually searchers find the information they want eventually, but that often requires multiple searches or clicks."

Powerset, a 2-1/2-year-old start-up, has licensed natural language processing technology and related machine processing methods developed over three decades at the Xerox PARC research center in Silicon Valley.