LabCorp Prices $500 Million in 2.20% Senior Notes Due 2017 and $500 Million in 3.75% Senior Notes Due 2022

<0> Laboratory Corporation of AmericaHoldingsStephen Anderson, 336-436-5076 </0>

Laboratory Corporation of AmericaHoldings (LabCorp) (NYSE: LH) announced today that it has priced its offering of $1 billion in senior notes. The offering consists of two tranches: $500 million aggregate principal amount of 2.20% Senior Notes due 2017 (the “2017 Notes”) and $500 million aggregate principal amount of 3.75% Senior Notes due 2022 (the “2022 Notes,” and together with the 2017 Notes, the “Notes”). The Notes will bear interest from August 23, 2012, payable semi-annually on August 23 and February 23, commencing on February 23, 2013. The closing of the offering is expected to occur on August 23, 2012, subject to the satisfaction of customary closing conditions. The Notes will be senior unsecured obligations and will rank equally with LabCorp’s existing and future senior unsecured debt.

LabCorp intends to use the net proceeds of this offering to repay certain amounts outstanding under its existing credit facility dated December 21, 2011, and for general corporate purposes.

The active joint book-running managers for the offering are BofA Merrill Lynch and Credit Suisse. Barclays and Wells Fargo Securities are acting as passive joint book-running managers. BB&T Capital Markets; Citigroup; Mitsubishi UFJ Securities; and TD Securities are acting as co-managers. The offering will be made pursuant to an effective shelf registration statement on Form S-3 filed with the Securities and Exchange Commission (the “SEC”). A copy of the prospectus and related prospectus supplement may be obtained from Merrill Lynch, Pierce, Fenner & Smith Incorporated, 4 World Financial Center, 250 Vesey Street, 7th Floor, New York, New York 10080 or by calling toll-free 1-800-294-1322 or from Credit Suisse Securities (USA) LLC, Attention: Prospectus Department, One Madison Avenue, New York, New York 10010 or by calling toll-free 1-800-221-1037 or by emailing: .

This press release does not constitute an offer to sell or a solicitation of an offer to buy the Notes or any other securities, nor shall there be any sale of these securities in any jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. The offering of these securities may be made only by means of the prospectus supplement and the accompanying prospectus.

Laboratory Corporation of America Holdings, an S&P 500 company, is a pioneer in commercializing new diagnostic technologies and the first in its industry to embrace genomic testing. With annual revenues of $5.5 billion in 2011, over 31,000 employees worldwide, and more than 220,000 clients, LabCorp offers more than 4,000 tests ranging from routine blood analyses to reproductive genetics to companion diagnostics. LabCorp furthers its scientific expertise and innovative clinical testing technology through its LabCorp Specialty Testing Group: The Center for Molecular Biology and Pathology, National Genetics Institute, ViroMed Laboratories, Inc., The Center for Esoteric Testing, Litholink Corporation, Integrated Genetics, Integrated Oncology, DIANON , Inc., Monogram Biosciences, Inc., Colorado Coagulation, and Endocrine Sciences. LabCorp conducts clinical trials testing through its LabCorp Clinical Trials division. LabCorp clients include physicians, government agencies, managed care organizations, hospitals, clinical labs, and pharmaceutical companies.