Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2	Oct 16, 2017	C	12,466	—	A	12,466	I	See Footnote
Common Stock^F1,F2	Oct 16, 2017	C	13,650	—	A	26,116	I	See Footnote
Common Stock^F1,F2	Oct 16, 2017	C	16,643	—	A	42,759	I	See Footnote
Common Stock^F2	Oct 16, 2017	C	2,282	$7.00	A	45,041	I	See Footnote
Common Stock^F1,F3	Oct 16, 2017	C	461,717	—	A	461,717	I	See Footnote
Common Stock^F1,F3	Oct 16, 2017	C	505,580	—	A	967,297	I	See Footnote
Common Stock^F1,F3	Oct 16, 2017	C	616,446	—	A	1,583,743	I	See Footnote
Common Stock^F3	Oct 16, 2017	C	84,526	$7.00	A	1,668,269	I	See Footnote
Common Stock^F1,F4	Oct 16, 2017	C	474,184	—	A	474,184	I	See Footnote
Common Stock^F1,F4	Oct 16, 2017	C	519,230	—	A	993,414	I	See Footnote
Common Stock^F1,F4	Oct 16, 2017	C	633,094	—	A	1,626,508	I	See Footnote
Common Stock^F4	Oct 16, 2017	C	86,809	$7.00	A	1,713,317	I	See Footnote

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	D/I
Series A Preferred Stock^F1,F2,F5	—	Oct 16, 2017	C	12,466	D	—	—	Common Stock	12,466	I
Series A Preferred Stock^F1,F3,F5	—	Oct 16, 2017	C	461,717	D	—	—	Common Stock	461,717	I
Series A Preferred Stock^F1,F4,F5	—	Oct 16, 2017	C	474,184	D	—	—	Common Stock	474,184	I
Series B Preferred Stock^F1,F2,F5	—	Oct 16, 2017	C	13,650	D	—	—	Common Stock	13,650	I
Series B Preferred Stock^F1,F3,F5	—	Oct 16, 2017	C	505,580	D	—	—	Common Stock	505,580	I
Series B Preferred Stock^F1,F4,F5	—	Oct 16, 2017	C	519,230	D	—	—	Common Stock	519,230	I
Series C Preferred Stock^F1,F2,F5	—	Oct 16, 2017	C	16,643	D	—	—	Common Stock	16,643	I
Series C Preferred Stock^F1,F3,F5	—	Oct 16, 2017	C	616,446	D	—	—	Common Stock	616,446	I
Series C Preferred Stock^F1,F4,F5	—	Oct 16, 2017	C	633,094	D	—	—	Common Stock	633,094	I
Convertible Promissory Note^F6,F2	$7.00	Oct 16, 2017	C	—	D	—	—	Common Stock	2,282	I
Convertible Promissory Note^F6,F3	$7.00	Oct 16, 2017	C	—	D	—	—	Common Stock	84,526	I
Convertible Promissory Note^F6,F4	$7.00	Oct 16, 2017	C	—	D	—	—	Common Stock	86,809	I

Explanation of responses

F1The shares of the Issuer's Preferred Stock automatically converted into shares of the Issuer's Common Stock, for no additional consideration, on a 1:1 basis immediately prior to the consummation of the Issuer's Initial Public Offering (the "IPO").
F2See additional Form 4 filed by Alloy Ventures 2002, LLC ("Ventures 2002") for additional members of this joint filing. The securities are directly held by Alloy Partners 2002, L.P. ("Alloy Partners 2002"). Ventures 2002, as the sole general partner of Alloy Partners 2002, may be deemed to beneficially own the securities held by Alloy Partners 2002. Craig Taylor, Douglas Kelly, John Shoch, Tony DiBona and Daniel Rubin are managing directors of Ventures 2002, and as such may be deemed to beneficially own the securities held by Alloy Partners 2002. Each Reporting Person disclaims beneficial ownership of such securities except to the extent of any pecuniary interest therein.
F3See additional Form 4 filed by Ventures 2002 for additional members of this joint filing. The securities are directly held by Alloy Ventures 2002, L.P. ("Alloy Ventures 2002"). Ventures 2002, as the sole general partner of Alloy Ventures 2002, may be deemed to beneficially own the securities held by Alloy Ventures 2002. Craig Taylor, Douglas Kelly, John Shoch, Tony DiBona and Daniel Rubin are managing directors of Ventures 2002, and as such may be deemed to beneficially own the securities held by Alloy Ventures 2002. Each Reporting Person disclaims beneficial ownership of such securities except to the extent of any pecuniary interest therein.
F4See additional Form 4 filed by Ventures 2002 for additional members of this joint filing. The securities are directly held by Alloy Ventures 2005, L.P. ("Alloy Ventures 2005"). Alloy Ventures 2005, LLC ("Ventures 2005"), as the sole general partner of Alloy Ventures 2005, may be deemed to beneficially own the securities held by Alloy Ventures 2005. Craig Taylor, Douglas Kelly, John Shoch, Tony DiBona, Daniel Rubin, Michael Hunkapiller and Ammar H. Hanafi are managing directors of Ventures 2005, and as such may be deemed to beneficially own the securities held by Alloy Ventures 2005. Each Reporting Person disclaims beneficial ownership of such securities except to the extent of any pecuniary interest therein.
F5The expiration date is not relevant to the conversion of these securities.
F6The amount reported in column 5 is the principal amount of Reporting Person's Convertible Promissory Note (the "Note"). The outstanding principal and accrued interest of the Note automatically converted into shares of the Issuer's Common Stock at the price per share available to the public as set forth in the final prospectus related to the Issuer's IPO upon the closing of the IPO.