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June 18, 2000
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EXHIBIT 99.10
[LETTERHEAD OF MORGAN STANLEY & CO. INCORPORATED]
Board of Directors
Healtheon/WebMD Corporation
400 The Lenox Building
3399 Peachtree Road, NE
Atlanta, GA 30326
Members of the Board:
We hereby consent to the inclusion of our opinion dated June 18, 2000 to the
Board of Directors of Healtheon/WebMD Corporation ("Healtheon/WebMD") as Annex C
to, and to the reference thereto under the caption "The Merger -- Opinions of
Healtheon/WebMD's financial advisor" in, the proxy statement/prospectus (the
"Proxy Statement/Prospectus") of Healtheon/WebMD, Medical Manager Corporation
and CareInsite, Inc. relating to the merger transaction between Healtheon/WebMD,
Medical Manager Corporation and CareInsite, Inc. In giving the foregoing
consent, we do not admit that we come within the category of persons whose
consent is required under the Securities Exchange Act of 1934, as amended, or
the rules and regulations promulgated thereunder, nor do we admit that we are
experts with respect to any part of the Proxy Statement/Prospectus within the
meaning of the term "experts" as used in the Securities Act of 1933, as amended,
or the rules and regulations promulgated thereunder.
June 18, 2000
Very truly yours,
/s/ MORGAN STANLEY & CO. INCORPORATED
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MORGAN STANLEY & CO. INCORPORATED
