Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	4,280,779	—	D	0	I	Directly owned by USVP IX
Common Stock, $0.001 per share^F1	Nov 8, 2018	J	856,155	—	A	856,155	D
Common Stock, $0.001 per share^F1	Nov 8, 2018	J	856,155	—	D	0	D
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	102,093	—	A	102,093	I	Directly owned by Steven Krausz
Common Stock, $0.001 per share^F3,F2	Nov 12, 2018	S	2,100	$0.9556	D	99,993	I	Directly owned by Steven Krausz
Common Stock, $0.001 per share^F2	Nov 13, 2018	S	2,400	$0.95	D	97,593	I	Directly owned by Steven Krausz
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	69,609	—	A	69,609	I	Directly owned by David Liddle
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	60,408	—	A	60,408	I	Directly owned by Paul Matteucci
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	85,851	—	A	85,851	I	Directly owned by Jonathan Root
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	60,336	—	A	60,336	I	Directly owned by Casey Tansey
Common Stock, $0.001 per share^F1,F2	Nov 8, 2018	J	82,370	—	A	82,370	I	Directly owned by Philip Young

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1Represents a pro-rata, in-kind distribution by U.S. Venture Partners IX, L.P. ("USVP IX"), without additional consideration, to its partners.
F2This report is one of two reports each on a separate Form 4; however, these forms are related to the same transaction being filed by the reporting persons. The shares are held of record by USVP IX. Presidio Management Group IX, LLC ("PMG IX") is the general partner of USVP IX and may be deemed to have sole voting and dispositive power over the shares held by USVP IX. Irwin Federman, a director of the Issuer, and each of Steven M. Krausz, David E. Liddle, Paul A. Matteucci, Jonathan D. Root, Casey Tansey, and Philip M. Young, are managing members of PMG IX, and may be deemed to share voting and dispositive power over the shares held by USVP IX. Such persons and entities disclaim beneficial ownership of shares held by USVP IX, except to the extent of any proportionate pecuniary interest therein.
F3The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $.95 to $.96, inclusive for sales made on November 12, 2018. The reporting persons undertake to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.