AMENDMENT NO. 1 TO AMENDED AND RESTATED CREDIT AGREEMENT

AMENDMENT NO. 1 dated as of July 13, 2016 (this “Amendment”) to AMENDED AND RESTATED CREDIT AGREEMENT dated as of December 19, 2014 (the “Revolving Credit Agreement”), among LABORATORY CORPORATION OF AMERICA HOLDINGS, a Delaware corporation (the “Borrower”), the LENDERS from time to time party thereto and BANK OF AMERICA, N.A., as Administrative Agent.

WHEREAS, the Borrower has requested that the Revolving Credit Agreement be amended as set forth herein; and

WHEREAS, the Administrative Agent and the Required Lenders executing this Amendment as a Lender are willing to amend the Revolving Credit Agreement on the terms set forth herein;

NOW, THEREFORE, in consideration of the premises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

Section 1. Defined Terms; References. Unless otherwise specifically defined herein, each term used herein that is defined in the Revolving Credit Agreement has the meaning assigned to such term in the Revolving Credit Agreement.

Section 2. Amendments. Each of the parties hereto agrees that, effective on the Amendment Effective Date, the definition of “Change of Control” in Section 1.01 of the Revolving Credit Agreement shall be amended and restated in its entirety as set forth below:

“Change in Control” means the occurrence of any of the following events: (a) any person or group (within the meaning of Rule 13d-5 of the Securities Exchange Act of 1934 as in effect on the date hereof) shall own directly or indirectly, beneficially or of record, Equity Interests representing more than 40% of the aggregate ordinary voting power represented by the issued and outstanding Equity Interests of the Borrower or (b) a majority of the seats (other than vacant seats) on the board of directors of the Borrower shall at any time cease to be occupied by persons (i) who were members of the board of directors on the July 13, 2016, (ii) who were nominated or elected to the board of directors, or whose nomination or election was approved, by individuals referred to in (i) constituting at the time of such election, nomination or approval at least a majority of the members of the board of directors or (iii) who were nominated or elected to the board of directors, or whose nomination or election was approved, by individuals referred to in clause (i) and (ii) above constituting at the time of such election, nomination or approval at least a majority of the board of directors.

Section 5. Governing Law. This Amendment shall be governed by, and construed in accordance with, the laws of the State of New York without regard to the conflicts of law principles thereto and to the extent that such principles would direct a matter to another jurisdiction.