Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
GLAXOSMITHKLINE PLC
  2. Issuer Name and Ticker or Trading Symbol
QUEST DIAGNOSTICS INC [DGX]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
980 GREAT WEST ROAD
3. Date of Earliest Transaction (Month/Day/Year)
06/07/2006
(Street)

BRENTFORD MIDDLESEX, X0 TW8 9GS
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock               36,504,308 (7) I by Corporation (6)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Contract to Sell (1) (2) (3) (4) (5) (1) (2) (3) (4) (5) 06/07/2006   (1)(2)(3)(4)(5) J   0 (1) (2) (3) (4) (5)     (1)(2)(3)(4)(5)   (1)(2)(3)(4)(5) Common Stock 2,000,000 (1) (2) (3) (4) (5) 0 (1) (2) (3) (4) (5) I by Corporation (6)
Contract to Sell (1) (2) (3) (4) (5) (1) (2) (3) (4) (5) 06/07/2006   (1)(2)(3)(4)(5) J   0 (1) (2) (3) (4) (5)     (1)(2)(3)(4)(5)   (1)(2)(3)(4)(5) Common Stock 2,000,000 (1) (2) (3) (4) (5) 0 (1) (2) (3) (4) (5) I by Corporation (6)
Contract to Sell (1) (2) (3) (4) (5) (1) (2) (3) (4) (5) 06/07/2006   (1)(2)(3)(4)(5) J   0 (1) (2) (3) (4) (5)     (1)(2)(3)(4)(5)   (1)(2)(3)(4)(5) Common Stock 2,000,000 (1) (2) (3) (4) (5) 0 (1) (2) (3) (4) (5) I by Corporation (6)
Contract to Sell (1) (2) (3) (4) (5) (1) (2) (3) (4) (5) 06/07/2006   (1)(2)(3)(4)(5) J   0 (1) (2) (3) (4) (5)     (1)(2)(3)(4)(5)   (1)(2)(3)(4)(5) Common Stock 2,000,000 (1) (2) (3) (4) (5) 0 (1) (2) (3) (4) (5) I by Corporation (6)
Contract to Sell (1) (2) (3) (4) (5) (1) (2) (3) (4) (5) 06/07/2006   (1)(2)(3)(4)(5) J   0 (1) (2) (3) (4) (5)     (1)(2)(3)(4)(5)   (1)(2)(3)(4)(5) Common Stock 2,000,000 (1) (2) (3) (4) (5) 0 (1) (2) (3) (4) (5) I by Corporation (6)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
GLAXOSMITHKLINE PLC
980 GREAT WEST ROAD
BRENTFORD MIDDLESEX, X0 TW8 9GS
    X    

Signatures

 Donald F. Parman, Vice President & Assoc General Counsel   06/09/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) On May 21, 2002, SmithKline Beecham Corporation ("SKB") and Lehman Brothers Finance S.A. ("Lehman") entered into five transactions (each, a "Transaction") governed by an ISDA Master Agreement, each of which initially related to 1,000,000 shares of Common Stock of the Issuer (the "Shares"). At the time of extension described below, each Transaction related to 2,000,000 Shares as a result of a stock split on June 20, 2005.
(2) On June 7, 2006, each Transaction was extended. As extended, the Transactions provide for SKB to deliver to Lehman, for settlement on November 11, 2010 ("Transaction 1"), August 10, 2012 ("Transaction 2"), April 12, 2010 ("Transaction 3"), June 10, 2011 ("Transaction 4") and January 12, 2012 ("Transaction 5"), a number of Shares (the "Settlement Shares") to be determined based on the formula described in the Reporting Person's filing on Form 4 dated June 8, 2002, as follows: If the price of the Shares determined near the original settlement date of a Transaction (the "Final Price") is at or below a specified Depreciation Floor ($41.19 per Share for Transaction 1, $40.60 for Transaction 2, $41.30 for Transaction 3, $40.96 for Transaction 4 and $40.73 for Transaction 5), SKB will be obligated to deliver all the Shares underlying that particular Transaction.
(3) If the Final Price is above the specified Depreciation Floor and at or below a specified Appreciation Cap as defined in each Transaction ($53.49 per Share for Transaction 1, $60.98 for Transaction 2, $52.08 for Transaction 3, $55.38 for Transaction 4 and $57.68 for Transaction 5), SKB will be obligated to deliver a number of Shares equal to the number of Shares underlying that particular Transaction multiplied by the Depreciation Floor divided by the Final Price. If the Final Price is above the specified Appreciation Cap, SKB will be obligated to deliver a number of Shares equal to the number of Shares underlying that particular Transaction multiplied by (i) 1.0 minus (ii) (a) the Appreciation Cap minus the Depreciation Floor divided by (b) the Final Price.
(4) In any case, Lehman is obligated to pay SKB under each Transaction upon settlement an amount equal to the sum of (i) the product of (A) the Settlement Shares multiplied by (B) the lesser of (x) the Extended Appreciation Cap ($63.88 for Transaction 1, $67.28 for Transaction 2, $62.75 for Transaction 3, $65.02 for Transaction 4, $66.15 for Transaction 5) and (y) the greater of (1) the Extended Depreciation Floor ($49.57) and (2) the price of the Shares determined near the extended settlement date of a Transaction (the "Extended Final Price"), plus (ii) the product of (A) the excess of 2,000,000 over the Settlement Shares multiplied by (continued in footnote 5)
(5) (B) if (x) the Extended Final Price is less than or equal to the Extended Depreciation Floor, the Extended Depreciation Floor minus the Extended Final Price, (y) the Extended Final Price is greater that the Extended Appreciation Cap, the Extended Appreciation Cap minus the Extended Final Price or (z) if the Extended Final Price is greater than the Extended Depreciation Floor and less than or equal to the Extended Appreciation Cap, zero. The Adjustment Letter evidencing the extension of the Transactions will be filed as an Exhibit to Amendment No. 5 to Schedule 13D to be filed by the Reporting Person.
(6) Shares are held of record by SKB, a wholly owned subsidiary of Reporting Person.
(7) Adjusted to reflect the two-for-one stock split effected by the Issuer on June 20, 2005.

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