Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Class A Common Stock^F2	Dec 15, 2017	C	2,071,223	$0.00	A	2,071,223	I	By SC US GF V Holdings, Ltd.
Class A Common Stock^F2	Dec 15, 2017	C	1,318,174	$0.00	A	1,318,174	I	By Sequoia Capital U.S. Growth Fund VI, L.P.
Class A Common Stock^F2	Dec 15, 2017	C	66,026	$0.00	A	66,026	I	By Sequoia Capital U.S. Growth VI Principals Fund, L.P.
Class A Common Stock^F2	Dec 15, 2017	J	2,071,223	$0.00	D	0	I	By SC US GF V Holdings, Ltd.
Class A Common Stock^F2	Dec 15, 2017	J	1,318,174	$0.00	D	0	I	By Sequoia Capital U.S. Growth Fund VI, L.P.
Class A Common Stock^F2	Dec 15, 2017	J	66,026	$0.00	D	0	I	By Sequoia Capital U.S. Growth VI Principals Fund, L.P.

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Class B Common Stock^F2,F3	—	Dec 15, 2018	C	2,071,223	D	—	—	Class A Common Stock	2,071,223	8,284,893	I
Class B Common Stock^F2,F3	—	Dec 15, 2018	C	1,318,174	D	—	—	Class A Common Stock	1,318,174	5,272,694	I
Class B Common Stock^F2,F3	—	Dec 15, 2018	C	66,026	D	—	—	Class A Common Stock	66,026	264,106	I

Explanation of responses

F1Represents a distribution of Class A Common Stock of the Issuer to partners or members and includes subsequent distributions by general partners or managing members to their respective partners or members.
F2SC US (TTGP), Ltd. is the general partner of SC U.S. Growth VI Management, L.P., which is the general partner of each of Sequoia Capital U.S. Growth Fund VI, L.P. and Sequoia Capital U.S. Growth VI Principals Fund, L.P. Sequoia Capital U.S. Growth Fund V, L.P. and Sequoia Capital USGF Principals Fund V, L.P. together own 100% of the outstanding shares held by SC US GF V Holdings, Ltd. SC US (TTGP), Ltd. is the general partner of SCGF V Management, L.P., which is the general partner of each of Sequoia Capital U.S. Growth Fund V, L.P. and Sequoia Capital USGF Principals Fund V, L.P. Each of the Reporting Persons disclaims beneficial ownership of these securities except to the extent of its pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purposes.
F3Each 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.

Remarks

* /s/ Jung Yeon Son, by power of attorney for Patrick W. Grady, a Director of SC US (TTGP), Ltd., which is the general partner of SC U.S. Growth VI Management, L.P., which is the general partner of each of Sequoia Capital U.S. Growth Fund VI, L.P. and Sequoia Capital U.S. Growth VI Principals Fund, L.P. ** /s/ Jung Yeon Son, by power of attorney for Patrick W. Grady, a Director of SC US (TTGP), Ltd., which is the general partner of SCGF V Management, L.P., which is the general partner of each of Sequoia Capital U.S. Growth Fund V, L.P. and Sequoia Capital USGF Principals Fund V, L.P. *** /s/ Jung Yeon Son, by power of attorney for Patrick W. Grady, a Director of SC US (TTGP), Ltd., which is the general partner of SCGF V Management, L.P., which is the general partner of each of Sequoia Capital U.S. Growth Fund V, L.P. and Sequoia Capital USGF Principals Fund V, L.P., which together own 100% of the outstanding shares of SC US GF V Holdings, Ltd.