NewMarket (NEU) 8-K Newmarket Corporation Approves a New Stock Repurchase Authorization

EXHIBIT 99.1

NEWMARKET CORPORATION APPROVES A NEW STOCK REPURCHASE AUTHORIZATION

Richmond, VA, December 13, 2018 - The Board of Directors of NewMarket Corporation (NYSE:NEU) approved a new share repurchase program and authorized management to repurchase up to $500 million of NewMarket’s outstanding common stock effective January 1, 2019 until December 31, 2021, as market conditions warrant and covenants under our existing debt agreements permit. NewMarket may conduct the share repurchases from time to time in the open market at prevailing market prices, in privately negotiated transactions, through block trades or pursuant to any trading plan that may be adopted in accordance with Rule10b5-1 of the Securities Exchange Act of 1934. The repurchase program does not require NewMarket to acquire any specific number of shares and may be terminated or suspended at any time.

This new authorization replaces NewMarket’s prior share repurchase program, which expires on December 31, 2018.

NewMarket Corporation, through its subsidiaries Afton Chemical Corporation and Ethyl Corporation, develops, manufactures, blends, and delivers chemical additives that enhance the performance of petroleum products. From custom-formulated additive packages to market-general additives, the NewMarket family of companies provides the world with the technology to make engines run smoother, machines last longer, and fuels burn cleaner.

Some of the information contained in this press release constitutes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Although NewMarket’s management believes its expectations are based on reasonable assumptions within the bounds of its knowledge of its business and operations, there can be no assurance that actual results will not differ materially from expectations.

Factors that could cause actual results to differ materially from expectations include, but are not limited to, the availability of raw materials and distribution systems; disruptions at manufacturing facilities, including single-sourced facilities; the ability to respond effectively to technological changes in our industry; failure to protect our intellectual property rights; failure to attract and retain a highly-qualified workforce; hazards common to chemical businesses; competition from other manufacturers; sudden or sharp raw material price increases; the gain or loss of significant customers; the

occurrence or threat of extraordinary events, including natural disasters and terrorist attacks; risks related to operating outside of the United States; the impact of fluctuations in foreign exchange rates; an information technology system failure or security breach; political, economic, and regulatory factors concerning our products; current and future governmental regulations; resolution of environmental liabilities or legal proceedings; our inability to realize expected benefits from investment in our infrastructure or from recent or future acquisitions, or our inability to successfully integrate recent or future acquisitions into our business; and other factors detailed from time to time in the reports that NewMarket files with the Securities and Exchange Commission, including the risk factors in Item 1A. “Risk Factors” of our 2017 Annual Report on Form10-K, which is available to shareholders upon request.

You should keep in mind that any forward-looking statement made by NewMarket in the foregoing discussion speaks only as of the date on which such forward-looking statement is made. New risks and uncertainties arise from time to time, and it is impossible for us to predict these events or how they may affect the Company. We have no duty to, and do not intend to, update or revise the forward-looking statements in this discussion after the date hereof, except as may be required by law. In light of these risks and uncertainties, you should keep in mind that the events described in any forward-looking statement made in this discussion, or elsewhere, might not occur.

FOR INVESTOR INFORMATION CONTACT:

  Brian D. Paliotti

  Investor Relations

  Phone: 804.788.5555

  Fax:     804.788.5688

  Email:investorrelations@newmarket.com