WARRANTS

From time to time, we have issued warrants to purchase shares of common stock. These warrants have been issued in connection with the financing transactions and consulting services. Our warrants are subject to standard anti-dilution provisions applicable to shares of our common stock.

Private Placement Warrants

In February 2017, we issued warrants to purchase 1,626,898 shares of our common stock at an exercise price of $8.25 in connection with our private placement sale of 1,626,898 shares of common stock. The warrants are exercisable for a period commencing 6 months and ending 30 months after the closing of the financing. We refer to these warrants as Private Placement Warrants - February 2017. We estimated the fair value of the Private Placement Warrants at $2,084,000 using the Black-Scholes option valuation model with the following assumptions: market prices of the stock of $4.91 per share, time to maturity of 3 years, volatility of 60%, zero expected dividend rate and risk free rate of 1.50%. The allocation of the fair value of these warrants was included in additional paid-in capital on the consolidated balance sheet.

In September 2017, we issued warrants to purchase 1,832,860 shares of our common stock at an exercise price of $4.85 in connection with our private placement sale of 1,745,581 shares of common stock. The warrants are exercisable for a period commencing 6 months and ending 36 months after the closing of the financing. We refer to these warrants as Private Placement Warrants - September 2017. We estimated the fair value of the Private Placement Warrants at $3.2 million using the Black-Scholes option valuation model with the following assumptions: market prices of the stock of $4.49 per share, time to maturity of 3 years, volatility of 60%, zero expected dividend rate and risk free rate of 1.59%. The allocation of the fair value of these warrants was included in additional paid-in capital on the consolidated balance sheet.

A roll-forward of warrant share activity from January 1, 2016 to September 30, 2016 is shown in the following table:



	Issued and Outstanding Warrants as of January 1, 2016	Warrants Issued	Warrants Exercised/ Expired			Issued and Outstanding Warrants as of September 30, 2016
Bridge Warrants	249,999	—	—			249,999
Consulting Warrants	117,778	—	(19,778	)	(1)	98,000
Financing Warrants	78,186	—	—			78,186
Underwriting Warrants	310,500	—	—			310,500
IR Consulting Warrants	48,000	—	—			48,000
Private Placement Warrants	—	2,096,724				2,096,724
Underwriting Warrants- Public Offering 2016		135,750				135,750
	804,463	2,232,474	(19,778	)		3,017,159


(1)	During the nine months ended September 30, 2016 there were 19,778 common stock warrants that were exercised through a cashless exercise which resulted in 19,693 shares being issued.

A roll-forward of warrant share activity from January 1, 2017 to September 30, 2017 is shown in the following table:



	Issued and Outstanding Warrants as of January 1, 2017	Warrants Issued	Warrants Exercised/ Expired			Issued and Outstanding Warrants as of September 30, 2017
Bridge Warrants	249,999	—	—			249,999
Consulting Warrants	98,000	—	(41,889	)	(1)	56,111
Financing Warrants	78,186	—	—			78,186
Underwriting Warrants	310,500	—	—			310,500
IR Consulting Warrants	48,000	—	(42,000	)	(2)	6,000
Private Placement Warrants - 2016	1,995,124	—	(89,281	)	(3)	1,905,843
Underwriting Warrants - Public Offering 2016	135,750	—	—			135,750
Private Placement Warrants - February 2017	—	1,626,898	—			1,626,898
Private Placement Warrants - September 2017	—	1,832,860	—			1,832,860
	2,915,559	3,459,758	(173,170	)		6,202,147


(1)	During the nine months ended September 30, 2017, there were 41,889 common stock warrants that were exercised through cashless exercises which resulted in 41,800 shares being issued.


(2)	During the nine months ended September 30, 2017, 42,000 warrants expired.


(3)	During the nine months ended September 30, 2017, there were 89,281 common stock warrants that were exercised through cashless exercises which resulted in 37,031 shares being issued.