Exhibit 10.2

QUEST DIAGNOSTICS INCORPORATED
Three Giralda Farms
Madison, New Jersey

January 31, 2011

Mr. Peter K. Hopkins
GlaxoSmithKline plc.
via Email

Dear Mr. Hopkins:

We understand you intend to sell approximately 30.8 million shares of your Quest Diagnostics Incorporated common stock. As discussed, we are willing to facilitate an orderly sale by purchasing a portion of these shares from you directly. Specifically, we are prepared to purchase 15,377,551 shares from you on the terms outlined in the attached term sheet.

Sincerely,

/s/ Michael G. Lukas

Michael G. Lukas
Vice President, Finance

AGREED AND ACCEPTED


GLAXOSMITHKLINE PLC

/s/ P.K. Hopkins

Name: P.K. Hopkins
Title: Authorized Signatory

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Summary of Terms

Securities	Quest Diagnostics Incorporated common stock (the “Common Stock”)
Seller	SB Holdings Capital Inc.
Buyer	Quest Diagnostics Incorporated
Number of Shares	15,377,551 shares
Price per Share	$54.30
Trade Date	January 31, 2011
Settlement Date	February 4, 2011

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