The company says that the move makes the most comprehensive view of the web and delivers the most relevant results.
Dominic Trigg, vice-president of search and director at InfoSpace Europe, said: "With continued explosive growth of online search, MSN Search is a terrific addition to our metasearch capability.
"As the only provider to have relationships with all four of the most popular algorithms, we are able to offer a search solution uniquely designed to provide end users with the most relevant results and support our partners' business agendas."
The search engine providers benefit from being included in a metasearch engine because it shows users the differences between the engines, allowing each provider to prove they provide top-quality results, and it also generates revenue.
Although many people believe search results across all four engines are the same, results can differ greatly between each engine.
A US study, conducted by InfoSpace's in the US, in conjunction with researchers at the University of Pittsburgh and Pennsylvania State University, evaluated 12,570 random queries run on MSN Search, Google, Yahoo! and Ask Jeeves. They found only 1.1% of first-page results were the same across all four engines.
InfoSpace has built a tool that allows consumers to compare the results of the leading engines for themselves. The new comparison search tool can be found .
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