THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

Quest Diagnostics Incorporated (DGX)

3/30/2006 Proxy Information

GlaxoSmithKline

SmithKline Beecham Corporation, a subsidiary of GlaxoSmithKline (“SmithKline Beecham”), owns 36,504,308 shares of Quest Diagnostics' common stock as of March 15, 2006, which it obtained on August 16, 1999 as consideration, together with $1.025 billion in cash (prior to giving effect to a $95 million post-closing purchase price reduction), for its sale of SBCL to Quest Diagnostics. SmithKline Beecham originally received 50,257,344 shares in the transaction (adjusted for the stock splits in May 2001 and June 2005). In addition to the two agreements discussed below, in connection with the purchase of SBCL, SmithKline Beecham agreed to indemnify Quest Diagnostics, on an after tax basis, against certain matters primarily related to taxes and billing and professional liability claims. At December 31, 2005, accounts payable and accrued expenses included $28 million due to SmithKline Beecham, primarily related to tax benefits associated with indemnifiable matters.

Stockholders Agreement

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a stockholders agreement. During the ten-year term of the stockholders agreement, SmithKline Beecham has the right to designate two nominees to the Quest Diagnostics' Board of Directors (or, if required by UK GAAP, three nominees if the Company's Board of Directors consists of more than ten directors) as long as SmithKline Beecham owns at least 20% of the outstanding common stock of Quest Diagnostics and one nominee to the Quest Diagnostics Board of Directors as long as SmithKline Beecham owns at least 10% of the outstanding common stock of Quest Diagnostics. The stockholders agreement imposes limitations on the right of SmithKline Beecham to sell or vote its shares and prohibits SmithKline Beecham from acquiring in excess of 29.5% of the outstanding common stock of Quest Diagnostics.

Clinical Trials Agreement

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a global clinical trials testing agreement, under which Quest Diagnostics would serve as the primary provider of SmithKline Beecham's clinical trials testing requirements for ten years. In December 2002, Quest Diagnostics entered into a new long-term agreement with GlaxoSmithKline (formed from the SmithKline Beecham and Glaxo Wellcome merger in December 2000) under which Quest Diagnostics will be the exclusive provider of central laboratory testing services to support GlaxoSmithKline's clinical trial testing in certain markets. In addition, on a selected basis, Quest Diagnostics will provide support for other early stage research and development activity. GlaxoSmithKline will pay Quest Diagnostics based upon a fee schedule attached to the global clinical trials agreement, subject to adjustment. During 2005, Quest Diagnostics billed approximately $69 million to GlaxoSmithKline with respect to services primarily performed under the clinical trials testing agreement. This amount represents approximately 1.3% of Quest Diagnostics' net revenues for 2005 and about 0.2% of GlaxoSmithKline's net revenues for 2005.

3/31/2005 Proxy Information

GlaxoSmithKline

Mr. Grant a former Vice Chairman of SmithKline Beecham plc. SmithKline Beecham Corporation, a subsidiary of GlaxoSmithKline, owns 18,252,154 shares of Quest Diagnostics' common stock as of March 15, 2005, which it obtained on August 16, 1999 as consideration, together with $1.025 billion in cash (prior to giving effect to a $95 million post-closing purchase price reduction), for its sale of SBCL to Quest Diagnostics. SmithKline Beecham Corporation (“SmithKline Beecham”) originally received 25,128,672 shares in the transaction (adjusted for the stock split in May 2001). On June 25, 2004, Quest Diagnostics repurchased 1,176,518 shares from SmithKline for $86.13 per share. On December 14, 2004, Quest Diagnostics repurchased 2,700,000 shares from SmithKline Beecham for $94.19 per share. The purchase price for each of these stock trades was a negotiated discount to the then current market price of Quest Diagnostics' common stock. In addition to the two agreements discussed below, in connection with the purchase of SBCL, SmithKline Beecham agreed to indemnify Quest Diagnostics, on an after tax basis, against certain matters primarily related to taxes and billing and professional liability claims. At December 31, 2004, accounts payable and accrued expenses included $28 million due to SmithKline Beecham, primarily related to tax benefits associated with indemnifiable matters.

Stockholders Agreement

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a stockholders agreement. During the ten-year term of the stockholders agreement, SmithKline Beecham has the right to designate two nominees to the Quest Diagnostics' Board of Directors (or, if required by UK GAAP, three nominees if the Company's Board of Directors consists of more than ten directors) as long as SmithKline Beecham owns at least 20% of the outstanding common stock of Quest Diagnostics and one nominee to the Quest Diagnostics Board of Directors as long as SmithKline Beecham owns at least 10% of the outstanding common stock of Quest Diagnostics. The stockholders agreement imposes limitations on the right of SmithKline Beecham to sell or vote its shares and prohibits SmithKline Beecham from acquiring in excess of 29.5% of the outstanding common stock of Quest Diagnostics.

Clinical Trials Agreement

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a global clinical trials testing agreement, under which Quest Diagnostics would serve as the primary provider of SmithKline Beecham's clinical trials testing requirements for ten years. In December 2002, Quest Diagnostics entered into a new long-term agreement with GlaxoSmithKline plc (formed from the SmithKline Beecham and Glaxo Wellcome merger in December 2000) under which Quest Diagnostics will be the exclusive provider of central laboratory testing services to support GlaxoSmithKline's global clinical testing requirements. In addition, on a selected basis, Quest Diagnostics will provide support for other early stage research and development activity. GlaxoSmithKline will pay Quest Diagnostics based upon a fee schedule attached to the global clinical trials agreement, subject to adjustment. During 2004, Quest Diagnostics billed approximately $74 million to GlaxoSmithKline with respect to services primarily performed under the clinical trials agreement. This amount represents approximately 1.5% of Quest Diagnostics' net revenues for 2004 and about 0.2% of GlaxoSmithKline's net revenues for 2004.

4/13/2004 Proxy Information

The Board of Directors has determined that John M. Ziegler and James F. Flaherty III are independent notwithstanding that they have certain relationships with the Company that the Board believes are not material. Mr. Ziegler is the President, Worldwide Consumer Healthcare of GlaxoSmithKline plc, which beneficially owns approximately 21% of the outstanding common stock of the Company. The common stock of Quest Diagnostics that GlaxoSmithKline plc ('GlaxoSmithKline') beneficially owns was issued in August 1999 in connection with the acquisition of SmithKline Beecham Clinical Laboratories, Inc. ('SBCL'). In connection with the acquisition, the Company entered into a clinical trials agreement. These transactions are described under 'Certain Relationships and Related Transactions'. In 2003, the Company billed approximately $50 million to GlaxoSmithKline with respect to services performed primarily under the clinical trials agreement. This amount represents about 0.1% of GlaxoSmithKline's net revenues for 2003. Mr. Ziegler was not involved with the negotiation of any of these arrangements.

Mr. Flaherty is the President and Chief Executive Officer of Health Care Property Investors ('HCPI'), a qualified real estate investment trust specializing in healthcare real estate. HCPI, or an affiliate, is the lessor of 14 of the Company's patient service centers. The Company has almost 2,000 patient service centers. The aggregate annual rent for the 14 patient service centers is approximately $530,000, which constitutes less than 0.2% of HCPI's annual revenues. Mr. Flaherty was not involved with the negotiation of any of these lease arrangements. In addition, Mr. Flaherty's brother-in-law is a tax partner with PricewaterhouseCoopers LLP, independent auditor of the Company. To the best knowledge of the Company, the Company has never had any professional relationship or contact with Mr. Flaherty's brother-in-law. Under the new NYSE director independence listing standards, Mr. Flaherty may not be eligible to continue to serve on the Company's Audit and Finance Committee and Governance Committee after the Company's 2005 annual meeting of stockholders. The Company is currently seeking guidance from the NYSE whether the relationship of Mr. Flaherty's brother-in-law would cause Mr. Flaherty not to be considered independent under the new NYSE director independence listing standards.

During 2003, OPCENTER billed Quest Diagnostics approximately $2.1 million for consulting and recruiting services provided in various areas including information technology. Mary Cirillo, a director of Quest Diagnostics, is the majority stockholder and Chairman of OPCENTER. Prior to March, 2003, Ms. Cirillo was a member of the Company's Compensation Committee. As of May 4, 2004, Ms. Cirillo will retire as a director of Quest Diagnostics. Quest Diagnostics expects to continue to receive services from OPCENTER during 2004.

GLAXOSMITHKLINE

SmithKline Beecham Corporation, a subsidiary of GlaxoSmithKline plc, owns 22,128,672 shares of Quest Diagnostics' common stock, which it obtained on August 16, 1999 as consideration, together with $1.025 billion in cash (prior to giving effect to a $95 million post-closing purchase price reduction), for its sale of SBCL to Quest Diagnostics. SmithKline Beecham Corporation ('SmithKline Beecham') originally received 25,128,672 shares in the transaction (adjusted for the stock split in May 2001). In addition to the two agreements discussed below, in connection with the purchase of SBCL, SmithKline Beecham agreed to indemnify Quest Diagnostics, on an after tax basis, against certain matters primarily related to taxes and billing and professional liability claims. At December 31, 2003, accounts payable and accrued expenses included $21 million due to SmithKline Beecham, primarily related to tax benefits associated with indemnifiable matters.

STOCKHOLDERS AGREEMENT

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a stockholders agreement. During the ten-year term of the stockholders agreement, SmithKline Beecham has the right to designate two nominees to the Quest Diagnostics' Board of Directors (or, if required by UK GAAP, three nominees if the Company's Board of Directors consists of more than ten directors) as long as SmithKline Beecham owns at least 20% of the outstanding common stock of Quest Diagnostics. The stockholders agreement imposes limitations on the right of SmithKline Beecham to sell or vote its shares and prohibits SmithKline Beecham from acquiring in excess of 29.5% of the outstanding common stock of Quest Diagnostics.

CLINICAL TRIALS AGREEMENT

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics entered into a global clinical trials testing agreement, under which SmithKline Beecham would use Quest Diagnostics as the primary provider of SmithKline Beecham's clinical trials testing requirements for ten years. In December 2002, Quest Diagnostics entered into a new long-term agreement with GlaxoSmithKline plc (formed from the SmithKline Beecham and Glaxo Wellcome merger in December 2000) under which Quest Diagnostics will be the exclusive provider of central laboratory testing services to support GlaxoSmithKline's global clinical testing requirements. In addition, on a selected basis, Quest Diagnostics will provide support for other early stage research and development activity. GlaxoSmithKline will pay Quest Diagnostics based upon a fee schedule attached to the global clinical trials agreement, subject to adjustment. During 2003, Quest Diagnostics billed approximately $50 million to GlaxoSmithKline with respect to services primarily performed under the clinical trials agreement. This amount represents approximately 1% of Quest Diagnostics' net revenues for 2003 and about 0.1% of GlaxoSmithKline's net revenues for 2003.

4/2/2003 Proxy Information

OPCENTER

During 2002, OPCENTER billed Quest Diagnostics approximately $1.4 million for services provided in help desk and network operations as well as services in connection with facility moves. Mary Cirillo, a director of Quest Diagnostics, is the majority stockholder and the Chief Executive Officer of OPCENTER. Quest Diagnostics expects to continue to receive such services from OPCENTER during 2003.

GLAXOSMITHKLINE

SmithKline Beecham Corporation, a subsidiary of GlaxoSmithKline plc, owns 22,128,672 shares of Quest Diagnostics' common stock which it obtained on August 16, 1999 as consideration, together with $1.025 billion in cash (prior to giving effect to a $95 million post-closing purchase price reduction), for its sale of SmithKline Beecham Clinical Laboratories, Inc. ('SBCL') to Quest Diagnostics.

STOCKHOLDERS AGREEMENT

Quest Diagnostics entered into a stockholders agreement with SmithKline Beecham upon the closing of the purchase of SBCL. During the ten-year term of the stockholders agreement, SmithKline Beecham has the right to designate two nominees to the Quest Diagnostics' Board of Directors (or, if required by UK GAAP, three nominees if the Company's Board of Directors consists of more than ten directors) as long as SmithKline Beecham owns at least 20% of the outstanding common stock of Quest Diagnostics. The stockholders agreement imposes limitations on the right of SmithKline Beecham to sell or vote its shares and prohibits SmithKline Beecham from acquiring in excess of 29.5% of the outstanding common stock of Quest Diagnostics.

DATA ACCESS AGREEMENT

At the closing of the acquisition of SBCL, Quest Diagnostics entered into a data access agreement under which SmithKline Beecham would have the right to use Quest Diagnostics' laboratory data. The agreement restricted disclosure of data that would identify the patient or payor without appropriate authorization. The agreement was terminated as of December 31, 2002 and GlaxoSmithKline paid Quest Diagnostics $3 million in connection with the termination.

CLINICAL TRIALS AGREEMENT

At the closing of the acquisition of SBCL, SmithKline Beecham and Quest Diagnostics had entered into a global clinical trials testing agreement, under which SmithKline Beecham would use Quest Diagnostics as the primary provider of SmithKline Beecham's clinical trials testing requirements for ten years. In December 2002, Quest Diagnostics entered into a new long term agreement with GlaxoSmithKline plc (formed from the SmithKline Beecham and Glaxo Wellcome merger in December 2000) under which Quest Diagnostics will be the exclusive provider of central laboratory testing services to support GlaxoSmithKline's global clinical testing requirements in North America and Europe. In addition, on a selected basis, Quest Diagnostics will provide support for other early stage research and development activity. SmithKline Beecham will pay Quest Diagnostics fees based upon a fee schedule attached to the global clinical trials agreement, subject to adjustment. Quest Diagnostics billed approximately $33 million to SmithKline Beecham with respect to services performed during 2002.