Item 5. MARKET FOR THE REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market Information

Our common stock is quoted on the NASDAQ Global Select Market under the symbol IDXX.

Holders of Common Stock

As of February 9, 2021, there were 395 holders of record of our common stock. Because the majority of our common stock is held by brokers and other institutions on behalf of stockholders, we are unable to estimate the total number of stockholders represented by these record holders.

Purchases of Equity Securities by the Issuer

During the three months ended December 31, 2020, we repurchased shares of common stock as described below:

(1) As of December 31, 2020, our Board of Directors had approved the repurchase of up to 73 million shares of our common stock in the open market or in negotiated transactions pursuant to the Company’s share repurchase program. The program was approved and announced on August 13, 1999, and the maximum number of shares that may be purchased under the program has been increased by the Board of Directors on numerous occasions. There is no specified expiration date for this repurchase program. There were no other repurchase programs outstanding during the three months ended December 31, 2020, and no repurchase programs expired during the period.

(2) During the three months ended December 31, 2020, we received 27,124 shares of our common stock that were surrendered by employees in payment for the required withholding taxes due on the vesting of restricted stock units and settlement of deferred stock units. In the above table, these shares are included in columns (a) and (b) but excluded from columns (c) and (d). These shares do not reduce the number of shares that may yet be purchased under the repurchase program.

During the year ended December 31, 2020, we repurchased approximately 0.7 million shares of our common stock in transactions made pursuant to our repurchase program and received approximately 0.06 million shares of common stock that were surrendered by employees in payment for the minimum required withholding taxes due on the vesting of restricted stock units and settlement of deferred stock units. Due to the uncertainty of the duration and magnitude of the COVID-19 pandemic and its impacts during 2020, we suspended our open market share repurchase activity beginning in the first quarter of 2020. The existing share repurchase program continues to be authorized by our Board of Directors and we have resumed share repurchases during the first quarter of 2021. See "Part II, Item 8. Financial Statements and Supplementary Data, Note 20. Repurchases of Common Stock" to the consolidated financial statements for the year ended December 31, 2020, included in this Annual Report on Form 10-K for further information.

Dividends

We have never declared or paid any cash dividends on our common stock. From time to time our Board of Directors may consider the declaration of a dividend. However, we have no intention to declare or pay a dividend at this time.

Stock Performance

This graph compares our total stockholder returns, the Total Return for the Standard & Poor’s (“S&P”) 500 Index, the Total Return for the S&P 500 Health Care Index, and the Total Return for the NASDAQ Stock Market Index (U.S. Companies) (the “NASDAQ Index”) prepared by the Center for Research in Security Prices. This graph assumes the investment of $100 on December 31, 2015, in IDEXX’s common stock, the S&P 500 Index, the S&P 500 Health Care Index, and the NASDAQ Index and assumes dividends, if any, are reinvested. Measurement points are the last trading days of the years ended December 2015 to 2020.