| Explanation of Responses: |
| (1) | Represents the number of shares sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary trade by the Reporting Person. |
| (2) | The price reported in Column 4 is a weighted average price calculated by the broker. These shares were sold as part of a block trade in multiple transactions at prices ranging from $115.16 to $117.80, inclusive. The Reporting Person
undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range
set forth in this footnote (2) with regard to the block trade. |
| (3) | This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person. |
| (4) | The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $116.13 to $116.99 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. |
| (5) | The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $117.43 to $117.78 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. |
| (6) | Each share of Class B Common Stock is convertible into one share of Class A Common Stock at the option of the holder and has no expiration date. |
| (7) | The transaction reported involved a gift by the Reporting Person of 2,000 shares of Class A Common Stock to the American Endowment Foundation FBO Kerrest Family Foundation, a donor advised fund. |
| (8) | The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $115.93 to $116.51 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. |
| (9) | The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $116.99 to $117.22 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. |
| (10) | Each Restricted Stock Unit ("RSU") represents the right to receive one share of the Issuer's Class A Common Stock. |
| (11) | 25% of the shares underlying the RSU vested on March 15, 2019, and the remaining shares underlying the RSU shall vest in 12 equal quarterly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer on each such date. |
| (12) | The shares subject to the option are fully vested and exercisable by the Reporting Person. |
| (13) | 25% of the shares subject to the option vested on August 1, 2016, and the remaining shares subject to the option shall vest in 36 equal monthly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer on each such date. The option is early exercisable by the Reporting Person. |
| (14) | 20% of the shares subject to the option vested on July 29, 2017, 20% of the shares subject to the option vested on July 29, 2018, and the remaining shares subject to the option shall vest in 36 equal monthly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer on each such date. The option is early exercisable by the Reporting Person. |
| (15) | 25% of the shares subject to the option vested on February 1, 2019 and the remaining shares subject to the option shall vest in 36 equal monthly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer through each vesting date. |
| (16) | 25% of the shares subject to the option shall vest on February 1, 2020 and the remaining shares subject to the option shall vest in 36 equal monthly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer through each vesting date. |
| (17) | 25% of the shares underlying the RSU shall vest on March 15, 2020, and the remaining shares underlying the RSU shall vest in 12 equal quarterly installments thereafter, subject to the Reporting Person's continuous employment with the Issuer on each such date. |