SAN FRANCISCO: Google Inc, owner of the world's most popular search engine, said Microsoft Corp's Bing is "copying" its query results. Microsoft denied the accusation and said the data in question comes from customers.

Google's own testing concluded that Bing was using its search results, Google Fellow Amit Singhal said in an e-mailed statement.

"We look forward to competing with genuinely new search algorithms out there, from Bing and others –algorithms built on core innovation, and not on recycled search results copied from a competitor," Singhal said.

A "small piece" of the information Microsoft uses to build search results comes from customers who choose to share their data — and that's what causes the overlap, said Harry Shum, corporate vice president at Bing, in a blog post. Microsoft uses more than 1,000 different signals and features to improve search results, he wrote.

"We learn from all of our customers," Shum said in the posting. "What we saw in today's story was a spy-novelesque stunt to generate extreme outliers" in some search rankings, he said. "It was a creative tactic by a competitor, and we'll take it as a back-handed compliment. But it doesn't accurately portray how we use opt-in customer data as one of many inputs to help improve our user experience."

In a panel discussion today with Google's Matt Cutts at the Farsight 2011 conference in San Francisco, Shum questioned whether Google can say it owns the data when a customer uses its search engine.

Search market share
Google is trying to preserve its lead in search as Bing increases market share. Bing had 12 percent of US searches in December, up from 11.8 percent the previous month, according to ComScore Inc in Reston, Virginia. Google had 66.6 percent, up from 66.2 percent.

"This seems pretty high-profile for them to take such a public stance," said Melise Blakeslee, founder and managing partner of Sequel Technology & IP Law Pllc, a firm in Washington that specializes in software and the Internet. "They're concerned about a competitor taking more of their market."

Website Search Engine Land earlier reported Google's allegation against Microsoft.