Under the terms of the deal, California-based Medstory employees will join Microsoft's recently formed Health Solutions Group which manages product development and delivery.
Financial terms were not disclosed as part of the agreement between the organisations.
Peter Neupert, corporate vice president for health strategy at Microsoft, and leader of the Health Solutions Group, said: "We were impressed with the ability of Medstory's unique technology to organise and surface the most relevant online health content."
According to an October 2006 study by the Pew Internet & American Life Project, eight million people in the US go online for health information every day.
Some 53 per cent of health-information seekers said that a recent search had an impact on how they take care of themselves or someone else.
Yet 22 per cent of respondents said they felt frustrated by a lack of information or an inability to find the data for which they were searching.
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