X0306 4 2017-09-15 0001447669 TWILIO INC TWLO 0001665731 Kirkpatrick Lee C/O TWILIO INC. 375 BEALE STREET, SUITE 300 SAN FRANCISCO CA 94105 1 Chief Financial Officer Class A Common Stock 2017-09-15 4 C 0 17292 0 A 75777 D Class A Common Stock 2017-09-15 4 S 0 3829 30.94 D 71948 D Class A Common Stock 2017-09-15 4 S 0 10000 30.8195 D 61948 D Employee Stock Option (right to buy) 1.24 2017-09-15 4 M 0 10000 0 D 2022-05-16 Class B Common Stock 10000 411076 D Class B Common Stock 2017-09-15 4 M 0 10000 0 A Class A Common Stock 10000 130261 D Class B Common Stock 2017-09-15 4 C 0 17292 0 D Class A Common Stock 17292 112969 D Employee Stock Option (right to buy) 10.09 2025-12-30 Class B Common Stock 175000 175000 D Employee Stock Option (right to buy) 31.96 2027-02-09 Class A Common Stock 95056 95056 D A portion of these shares represent Restricted Stock Units ("RSUs"). Each RSU represents the contingent right to receive one share of the Issuer's Class A common stock. Represents the number of shares sold to cover the statutory 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 minimum statutory tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary sale by the reporting person. The sales reported were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.53 to $31.45 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. The option is fully vested and exercisable by the reporting person. 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. A portion of these shares represent Restricted Stock Units ("RSU's). Each RSU represents a contingent right to receive one share of Issuer's Class B Common Stock. The shares subject to this option vest in 34 equal monthly installments, with the first installment on July 15, 2016. The option is early exercisable by the reporting person. The Stock Option ("Option") shall vest as follows: 1/4th of the Option shall vest on January 1, 2018, and 1/48th of the Option shall vest monthly thereafter, subject to continued service to the Issuer on each vesting date. /s/ Mariam Sattar as attorney in fact for Reporting Person 2017-09-19