On November 18, 2016, the Company completed a public offering of 714,286 shares of common stock with accompanying warrants to purchase an aggregate of 1,428,571 million shares of common stock. The stock and warrants were sold in combination, with two warrants for each share of common stock sold, a Series A warrant and a Series B warrant, each representing the right to purchase one share of common stock. The purchase price for each share of common stock and accompanying warrants was $35. The shares of common stock were immediately separable from the warrants and were issued separately. The initial per share exercise price of the Series A warrants was $50.05 and the per share exercise price of the Series B warrants was $60.20, each subject to adjustment as specified in the warrant agreements. The Series A warrants are exercisable until the four year anniversary of the issuance date. The Series B warrants expired on December 31, 2017 and none were exercised prior to expiration. The Series A warrants may be exercised at any time until they expire. The warrants include a provision that if the Company were to enter into a certain transaction, as defined in the agreement, the warrants would be purchased from the holder for cash. Accordingly, the Company recorded the warrants as a liability at their estimated fair value on the issuance date, which was $15.7 million, and changes in estimated fair value will be recorded as non-cash income or expense in the Company’s condensed consolidated statements of operations at each subsequent period. At September 30, 2018, the fair value of the warrant liability was $19,000, which resulted in non-cash income of $605,000 and $3.6 million for the three and nine months ended September 30, 2018, respectively. At September 30, 2017, the fair value of the warrant liability was $10.7 million, which resulted in non-cash expense of $4.1 million for the three months ended September 30, 2017 and non-cash income of $2.0 million for the nine months ended September 30, 2017. In accordance with U.S. GAAP, the warrants were valued on the date of grant using a Monte Carlo simulation. 

 

The assumptions used by the Company are summarized in the following table:

 

 

On October 10, 2014, the Company raised net proceeds of $19.1 million through the sale of 401,703 units at a price of $51.45 per unit to certain institutional investors in a registered direct offering. Each unit consisted of one share of the Company’s common stock and a warrant to purchase 0.5 shares of common stock. The warrants, exercisable for an aggregate of 200,852 shares of common stock, have an exercise price of $61.25 per share and a life of five years. The warrants vested immediately and expire on October 10, 2019.

  

The warrants issued in conjunction with the registered direct offering in October 2014 include a provision that if the Company were to enter into a certain transaction, as defined in the agreement, the warrants would be purchased from the holder at a premium. Accordingly, the Company recorded the warrants as a liability at their estimated fair value on the issuance date, which was $7.4 million, and changes in estimated fair value are being recorded as non-cash income or expense in the Company’s condensed consolidated statement of operations at each subsequent period. At September 30, 2018, the fair value of the warrant liability was $200.00, which resulted in non-cash income of $21,000 and $415,000 for the three and nine months ended September 30, 2018, respectively. At September 30, 2017, the fair value of the warrant liability was $2.0 million, which resulted in non-cash expense of $1.0 million for the three months ended September 30, 2017 and non-cash income of $0.2 million for the nine months ended September 30, 2017.  In accordance with U.S. GAAP, the warrants were valued on the date of grant using the Black-Scholes valuation model which approximates the value derived using a Monte Carlo simulation.

 

The assumptions used by the Company are summarized in the following table:

 

 

The following table summarizes the estimated fair value of the warrant liability

:

 

 

On December 26, 2017, the Company entered into a consulting agreement for advisory services for a period of six months. As compensation for such services, the consultant was paid an upfront payment, is paid a monthly fee and on January 24, 2018, was issued a warrant exercisable for 714 shares

approximated $9,000 and

table:

 

A summary of warrant activity for the Company for the nine months ended September 30, 2018 is as follows:

 

 

A summary of all outstanding and exercisable warrants as of September 30, 2018 is as follows: