(Burlington, N.C.) Laboratory Corporation of America® Holdings (LabCorp®) (NYSE: LH) announced today that for the period of March 12, 2010 to September 11, 2010, its Zero Coupon Convertible Subordinated Notes due 2021 (Zero Coupon Notes) will, subject to the terms of the Zero Coupon Notes, accrue contingent cash interest at a rate of no less than 0.125% of the average market price of a Zero Coupon Note for the five trading days ended March 9, 2010, in addition to the continued accrual of the original issue discount. Contingent cash interest, which the Company has determined to be approximately $1.23 per Note, will be payable to holders of the Zero Coupon Notes as of the record date, which is August 27, 2010. The payment of contingent cash interest is expected to be made on September 14, 2010.

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 $4.7 billion in 2009, over 28,000 employees worldwide, and more than 220,000 clients, LabCorp offers clinical assays ranging from routine blood analyses to HIV and genomic testing. LabCorp combines its expertise in innovative clinical testing technology with its Centers of Excellence: The Center for Molecular Biology and Pathology, National Genetics Institute, ViroMed Laboratories, Inc., The Center for Esoteric Testing, Litholink Corporation, DIANON Systems, Inc., US LABS, Monogram Biosciences, Inc. and Esoterix and its Colorado Coagulation, Endocrine Sciences, and Cytometry Associates laboratories. LabCorp conducts clinical trial testing through its Esoterix Clinical Trials Services division. LabCorp clients include physicians, government agencies, managed care organizations, hospitals, clinical labs, and pharmaceutical companies. To learn more about our organization, visit our Web site at: www.labcorp.com.