Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2	May 8, 2018	C	3,514,161	—	A	4,270,065	I	By Highland Capital Partners VI Limited Partnership
Common Stock^F1,F3	May 8, 2018	C	1,926,577	—	A	2,340,874	I	By Highland Capital Partners VI-B Limited Partnership
Common Stock^F1,F4	May 8, 2018	C	174,059	—	A	211,495	I	By Highland Entrepreneurs' Fund VI Limited Partnership
Common Stock^F1	May 8, 2018	C	1,093,318	—	A	1,093,318	I	By Highland Capital Partners VII Limited Partnership
Common Stock^F1	May 8, 2018	C	264,931	—	A	264,931	I	By Highland Capital Partners VII-B Limited Partnership
Common Stock^F1	May 8, 2018	C	385,824	—	A	385,824	I	By Highland Capital Partners VII-C Limited Partnership
Common Stock^F1	May 8, 2018	C	34,258	—	A	34,258	I	By Highland Entrepreneurs' Fund VII Limited Partnership

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series B Convertible Preferred Stock^F1,F2	—	May 8, 2018	C	4,794,437	D	—	—	Common Stock	2,397,218	I
Series B Convertible Preferred Stock^F1,F3	—	May 8, 2018	C	2,628,466	D	—	—	Common Stock	1,314,233	I
Series B Convertible Preferred Stock^F1,F4	—	May 8, 2018	C	237,472	D	—	—	Common Stock	118,736	I
Series C Convertible Preferred Stock^F1,F2	—	May 8, 2018	C	1,544,087	D	—	—	Common Stock	772,043	I
Series C Convertible Preferred Stock^F1,F3	—	May 8, 2018	C	846,518	D	—	—	Common Stock	423,259	I
Series C Convertible Preferred Stock^F1,F4	—	May 8, 2018	C	76,480	D	—	—	Common Stock	38,240	I
Series D Convertible Preferred Stock^F1,F2	—	May 8, 2018	C	689,800	D	—	—	Common Stock	344,900	I
Series D Convertible Preferred Stock^F1,F3	—	May 8, 2018	C	378,171	D	—	—	Common Stock	189,085	I
Series D Convertible Preferred Stock^F1,F4	—	May 8, 2018	C	34,166	D	—	—	Common Stock	17,083	I
Series E Convertible Preferred Stock^F1,F5	—	May 8, 2018	C	1,149,874	D	—	—	Common Stock	574,937	I
Series E Convertible Preferred Stock^F1,F6	—	May 8, 2018	C	278,637	D	—	—	Common Stock	139,318	I
Series E Convertible Preferred Stock^F1,F7	—	May 8, 2018	C	405,783	D	—	—	Common Stock	202,891	I
Series E Convertible Preferred Stock^F1,F8	—	May 8, 2018	C	36,031	D	—	—	Common Stock	18,015	I
Series F Convertible Preferred Stock^F1,F5	—	May 8, 2018	C	1,036,762	D	—	—	Common Stock	518,381	I
Series F Convertible Preferred Stock^F1,F6	—	May 8, 2018	C	251,227	D	—	—	Common Stock	125,613	I
Series F Convertible Preferred Stock^F1,F7	—	May 8, 2018	C	365,866	D	—	—	Common Stock	182,933	I
Series F Convertible Preferred Stock^F1,F8	—	May 8, 2018	C	32,486	D	—	—	Common Stock	16,243	I

Explanation of responses

F1Each share of preferred stock automatically converted into Common Stock on a 1-for-2 basis upon the closing of the Issuer's initial public offering. The shares have no expiration date.
F2The shares are held directly by Highland Capital Partners VI Limited Partnership ("Highland Capital VI"). The general partner of Highland Capital VI is Highland Management Partners VI Limited Partnership ("HMP VI LP"). The general partner of HMP VI LP is Highland Management Partners VI, Inc. ("Highland Management"). Each of HMP VI LP and Highland Management disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F3The shares are held directly by Highland Capital Partners VI-B Limited Partnership ("Highland Capital VI-B"). The general partner of Highland Capital VI-B is HMP VI LP. The general partner of HMP VI LP is Highland Management. Each of HMP VI LP and Highland Management disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F4The shares are held directly by Highland Entrepreneurs' Fund VI Limited Partnership ("Highland VI Entrepreneurs' Fund"). The general partner of Highland VI Entrepreneurs' Fund is HEF VI Limited Partnership ("HEF"). The general partner of HEF is Highland Management. Each of HEF and Highland Management disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F5The shares are held directly by Highland Capital Partners VII Limited Partnership ("Highland Capital VII"). The general partner of Highland Capital VII is Highland Management Partners VII Limited Partnership ("HMP VII LP"). The general partner of HMP VII LP is Highland Management Partners VII, LLC ("HMP VII LLC"). Each of HMP VII LP and HMP VII LLC disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F6The shares are held directly by Highland Capital Partners VII-B Limited Partnership ("Highland Capital VII-B"). The general partner of Highland Capital VII-B is HMP VII LP. The general partner of HMP VII LP is HMP VII LLC. Each of HMP VII LP and HMP VII LLC disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F7The shares are held directly by Highland Capital Partners VII-C Limited Partnership ("Highland Capital VII-C"). The general partner of Highland Capital VII-C is HMP VII LP. The general partner of HMP VII LP is HMP VII LLC. Each of HMP VII LP and HMP VII LLC disclaims Section 16 beneficial ownership of all shares except to the extent of their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.
F8The shares are held directly by Highland Entrepreneurs' Fund VII Limited Partnership ("Highland VII Entrepreneurs' Fund"). The general partner of Highland VII Entrepreneurs' Fund is HMP VII LP. The general partner of HMP VII LP is HMP VII LLC. Each of HMP VII LP and HMP VII LLC disclaims Section 16 beneficial ownership of all shares except to the extent of his their pecuniary interest, if any, therein. This report shall not be deemed to be an admission that the reporting persons are the beneficial owners of such securities for purposes of Section 16 or for any other purpose.

Remarks

Because no more than 10 reporting persons can file any one Form 4 through the Securities and Exchange Commission's EDGAR system, Highland Entrepreneurs' Fund VII Limited Partnership and HEF VI Limited Partnership have filed a separate Form 4. The Reporting Persons are jointly filing this Form 4 pursuant to Rule 16a-3(j) under the Exchange Act.