Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1	May 24, 2017	S	404,414	$5.10	D	7,175,634	I	By Sequoia Capital XII, L.P.
Common Stock^F1	May 24, 2017	S	43,222	$5.10	D	766,910	I	By Sequoia Capital XII Principals Fund, LLC
Common Stock^F1	May 24, 2017	S	15,133	$5.10	D	268,500	I	By Sequoia Technology Partners XII, L.P.
Common Stock^F2	May 24, 2017	S	35,660	$5.10	D	632,728	I	By Sequoia Capital U.S. Growth Fund IV, L.P.
Common Stock^F2	May 24, 2017	S	1,571	$5.10	D	27,875	I	By Sequoia Capital USGF Principals Fund IV, L.P.

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1SC XII Management, LLC ("SC XII Management") is the general partner of Sequoia Capital XII, L.P. and Sequoia Technology Partners XII, L.P. and is the managing member of Sequoia Capital XII Principals Fund, LLC. As a result, SC XII Management may be deemed to share voting and dispositive power with respect to the shares held by Sequoia Capital XII, L.P., Sequoia Technology Partners XII, L.P. and Sequoia Capital XII Principals Fund, LLC. 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.
F2SC US (TTGP), Ltd. ("SC TTGP") is the general partner of SCGF IV Management, L.P. ("SCGF IV Management"), which is the general partner of Sequoia Capital US Growth Fund IV, L.P. and Sequoia Capital USGF Principals Fund IV, L.P. As a result, SC TTGP and SCGF IV Management may be deemed to share voting and dispositive power with respect to the shares held by Sequoia Capital US Growth Fund IV, L.P. and Sequoia Capital USGF Principals Fund IV, L.P. Each of the filing 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.