Stockholders' Equity | Common Stock: The Company had a prior sales agreement with B. Riley for its ATM program, which expired on April 16, 2018, under which the Company could issue and sell up to an aggregate of $60.0 million of shares of its common stock. On March 9, 2018, the Company entered into a new agreement with B. Riley for the sale of up to $14.7 million of the Company’s common stock under the ATM program, pursuant to a registration statement filed on March 9, 2018 for an aggregate of $70 million of the Company’s securities, which became effective on April 16, 2018. The ATM program amount was increased by $25.0 million in November 2018. Under the ATM program, the Company may issue and sell common stock from time to time through B. Riley acting as agent, subject to limitations imposed by the Company and subject to B. Riley’s acceptance, such as the number or dollar amount of shares registered under the registration statement to which the offering relates. B. Riley is entitled to a commission of up to 3% of the gross proceeds from the sale of common stock sold under the ATM program. During the years ended December 31, 2018 and 2017, the Company sold 35,888,772 and 5,239,815 shares of common stock under the new and expired ATM programs, respectively, and realized net proceeds of approximately $22.0 million and $3.5 million during the years ended December 31, 2018 and 2017, respectively. At December 31, 2018, the Company has approximately $20.3 million available under its current ATM program and $30.3 million available under its current shelf registration for the issuance of equity, debt or equity-linked securities unrelated to the current ATM program. During the year ended December 31, 2018, the Company issued an aggregate of 131,826 shares of its common stock upon the vesting of restricted stock units issued to the Company’s board of directors. The Company also issued an aggregate of 127,628 shares of its common stock to its certain board members for payment of deferred fees. On May 3, 2017, the Company closed an underwritten public offering of 18,619,301 shares of its common stock, par value $0.001 per share, together with Series A warrants (“Series A Warrants”) to purchase up to an aggregate of 13,964,476 shares of its common stock and Series B warrants (“Series B Warrants”) to purchase up to an aggregate of 13,964,476 shares of its common stock. Series A Warrants had an exercise price of $0.75 per share of common stock and expired thirteen months following the Exercisable Date (defined below). Series B Warrants have an exercise price of $1.05 per share of common stock and will expire five years following the Exercisable Date. The net proceeds from this public offering was approximately $12.8 million. The Company issued to the underwriter warrants to purchase up to an aggregate of 1,117,158 shares of common stock, with an exercise price of $0.9375, which represents 125% of the public offering price per combined share and related warrants. The underwriter warrant expires five years following the Exercisable Date. Other than the exercise price, the terms of the underwriter warrants are the same as the Series B Warrants. In May 2017, the Company did not have a sufficient number of authorized shares of common stock to cover the shares issuable upon exercise of the warrants issued in the May 2017 public offering and therefore classified the fair value of the warrants as a derivative liability at June 30, 2017. On August 8, 2017, the Company’s shareholders approved the amendment of the Company’s amended and restated Certificate of Incorporation (the “Charter Amendment”) increasing the shares of authorized capital stock from 82,000,000 shares to 162,000,000 shares and increasing the number of authorized shares of common stock from 80,000,000 to 160,000,000 shares. The fair value of these warrants was re-measured on August 10, 2017, the date the warrants became exercisable (the “Exercisable Date”), with the increase in value recorded as a loss in the statement of operations. The fair value of the warrants at August 10, 2017 was reclassified then from liability to equity. In December 2017, the Company sold an aggregate of 624,246 shares of its common stock to its directors and executive officers and to certain of its employees at a per share purchase price of $0.48. The Company realized gross proceeds of approximately $300,000 (see Note 4 – Related Party Transactions). During the year ended December 31, 2017, the Company entered into warrant exchange agreements whereby the Company agreed to exchange with various investors (the “Investors”) Series A warrants issued in its May 2017 public offering of common stock and warrants. The exchanged warrants provided for the purchase of up to an aggregate of 9,886,250 shares of the Company’s common stock at an exercise price of $0.75, with an expiration date of September 10, 2018. The Company issued an aggregate of 2,471,561 shares of common stock to the Investors in exchange for these warrants. Restricted Stock Units During the year ended December 31, 2018 and 2017, the Company granted an aggregate of 94,500 and 112,931 restricted stock units (“RSUs”) to its officers and directors under its 2013 Stock Incentive Plan with a weighted average grant date fair value of $0.70 and $2.15 per share, respectively. These RSUs vest over various dates through October 2019. During the year ended December 31, 2018 and 2017, compensation expense recorded for these RSUs was $93,000 and $88,000, respectively. Unrecognized compensation expense as of December 31, 2018 and 2017 was $23,000 and $50,000, respectively. The expected weighted average period for the expense to be recognized is 0.34 years. During the year ended December 31, 2018, no RSUs were forfeited and 46,517 RSUs were forfeited during the year ended December 31, 2017. Preferred Stock The Company is authorized to issue up to 2,000,000 shares of preferred stock in one or more series without stockholder approval. The Company’s board of directors has the discretion to determine the rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences, of each series of preferred stock. Of the 2,000,000 shares of preferred stock authorized, the Company’s board of directors has designated (all with par value of $0.001 per share) the following: As of December 31, 2018 and 2017 Preferred Shares Outstanding Liquidation Preference (Per Share) Total Liquidation Preference Series C-2 150,000 10.0 1,500,000 Series C-3 104,000 10.0 1,040,000 Series D 73,962 21.0 1,553,202 Series E 89,623 49.2 4,409,452 Series F 2,000 1,000 2,000,000 Total 419,585 10,502,654 On November 9, 2017, the Company entered into a securities purchase agreement with Elliott, pursuant to which, on November 16, 2017, the Company sold $2.0 million of its Series F convertible preferred stock (“Series F Stock”) at $1,000 per share. Based on the terms of the Series F Stock, the conversion price was set at $0.162 on April 2, 2018, and the shares are currently convertible anytime at Elliott’s option. The Series F Stock will be mandatorily convertible if certain equity conditions are met. As of December 31, 2018, the last condition had not been met, which condition is the subordination of the outstanding Series C-3 preferred stock to the Series F Stock. Therefore, the Series F Stock is not mandatorily convertible as of December 31, 2018; the conversion price per share of $0.162, however, remains fixed, subject to anti-dilution adjustment, including full ratchet. When and if that condition is met, the Series F Stock will be mandatorily convertible. Pursuant to the terms of the Series F Stock, a holder will be prohibited from converting shares of Series F Stock into shares of common stock if, as a result of such conversion, (i) such holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Company’s common stock then issued and outstanding, or (ii) the Company would issue shares in an amount equal to or greater than 13,336,939 shares, which is 20% of the shares of common stock outstanding on November 9, 2017, unless the Company has received the approval of its stockholders for such overage. The Series F Stock is non-voting and has no dividend right outside of receiving dividends in the same form as the Company pays to holders of shares of its common stock. As long as any of the Series F non-voting convertible preferred stock is outstanding, the Company cannot, without the consent of a majority of the Series F holders, incur any indebtedness other than trade payables incurred in the ordinary course of business consistent with past practice, and letters of credit incurred in an aggregate amount of $3.0 million at any point in time. In the event of the Company’s liquidation, dissolution, or winding up, holders of the Series F Stock will receive a payment equal to $1,000 per share of Series F Stock, subject to adjustment, before any proceeds are distributed to the holders of common stock. Shares of the Series F Stock will rank: ● senior to all common stock and the Series C-2, Series C-3 Convertible Preferred Stock (subject to the Company obtaining any consent, waiver or other authorization from the holders of the Series C-3 Convertible Preferred Stock necessary for the subordination of the Series C-3 Convertible Preferred Stock to the Series F Preferred Stock), Series D Non-Voting Convertible Preferred Stock, Series E Non-Voting Convertible Stock; and ● senior to any class or series of capital stock hereafter created. in each case, as to distributions of assets upon our liquidation, dissolution or winding up whether voluntarily or involuntarily. As a part of the financing, the Company also entered into a registration rights agreement with Elliott whereby Elliott can demand that the Company register the shares issuable upon exercise of the warrants, and shares issuable upon conversion of the Series F Stock, if issued. The backstop agreement (see Warrant section of this Note) provides that until the later of (x) the date that no Series F preferred shares are outstanding and (y) the date the no warrants issued under the backstop agreement are outstanding, the Company may not issue any securities in a “variable rate transaction” other than at-the-market offerings through a registered broker-dealer or offerings of the Series F preferred stock. A “variable rate transaction” is a transaction on terms more favorable than those of the backstop agreement and the Series F preferred stock, in which the Company issues any convertible securities either (A) at a conversion, exercise or exchange rate or other price that is based upon and/or varies with the trading prices of or quotations for the shares of the Company’s common Stock at any time after the initial issuance of such convertible securities, or (B) with a conversion, exercise or exchange price that is subject to being reset at some future date after the initial issuance of such convertible securities or upon the occurrence of specified or contingent events directly or indirectly related to the business of the Company or the market for its common stock, other than pursuant to a customary “weighted average” anti-dilution provision or (ii) enters into any agreement (other than an at-the-market offering through a registered broker-dealer) whereby the Company may sell securities at a future determined price (other than standard and customary “preemptive” or “participation” rights). The following terms and conditions apply to the Series C, Series D, Series E and Series F non-voting convertible preferred stock outstanding at December 31, 2018 and 2017: Dividends Fundamental Transactions- Redemption Listing- Series C-2 and Series C-3 Non-Voting Convertible Preferred Stock and Warrants The Series C-2 non-voting preferred stock and Series C-3 non-voting preferred stock have identical rights, privileges and terms and are referred to collectively as the “Series C Stock.” Each share of Series C Stock is convertible into 10 shares of common stock at any time at the holder’s option at a conversion price of $1.00 per share. In the event of the Company’s liquidation, dissolution, or winding up, holders of the Series C Stock will receive a payment equal to $10.00 per share of Series C Stock, subject to adjustment, before any proceeds are distributed to the holders of common stock. Shares of the Series C Stock will not be entitled to receive any dividends, unless and until specifically declared by the Company’s board of directors. The Series C Preferred Stock ranks senior to the Company’s common stock; senior Series D Non-Voting Convertible Preferred Stock Each share of Series D non-voting convertible preferred stock is convertible into 20 shares of common stock (subject to adjustment) at a per share price of $0.35 at any time at the option of the holder, except that a holder will be prohibited from converting shares of Series D non-voting convertible preferred stock into shares of common stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Company’s common stock then issued and outstanding. In the event of the Company’s liquidation, dissolution or winding up, holders of Series D non-voting convertible preferred stock will receive a payment equal to $21.00 per share of Series D non-voting convertible preferred stock on parity with the payment of the liquidation preference due the Series E non-voting convertible preferred stock, but before any proceeds are distributed to the holders of common stock, the Series C-2 non-voting convertible preferred stock. The Series D non-voting convertible preferred stock ranks senior to the Company’s common stock; senior to any class or series of capital stock created after the issuance of the Series D non-voting convertible preferred stock; senior to the Series C-2 non-voting convertible preferred stock and the Series C-3 non-voting convertible preferred stock; on parity with the Series E non-voting convertible preferred stock; and junior to the Series F non-voting convertible preferred stock. As long as any of the Series D non-voting convertible preferred stock is outstanding, the Company cannot, without the consent of a majority of the Series D holders, incur any indebtedness other than indebtedness existing prior to September 15, 2014, trade payables incurred in the ordinary course of business consistent with past practice, and letters of credit incurred in an aggregate amount of $3.0 million at any point in time. In addition to the debt restrictions above, as long as any shares of the Series D non-voting convertible preferred stock are outstanding, the Company cannot, among others things: create, incur, assume or suffer to exist any encumbrances on any of its assets or property; or redeem, purchase or otherwise acquire or pay or declare any dividend or other distribution on any junior securities. Series E Non-Voting Convertible Preferred Stock Each share of Series E non-voting convertible preferred stock was originally convertible into 21.8667 shares of the Company’s common stock (subject to adjustment) at a per share price of $0.75 at any time at the option of the holder, except that a holder will be prohibited from converting shares of Series E non-voting convertible preferred stock into shares of common stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Company’s common stock then issued and outstanding. In the event of the Company’s liquidation, dissolution or winding up, holders of Series E preferred stock will receive a payment equal to $49.20 per share of Series E non-voting convertible preferred stock on parity with the payment of the liquidation preference due the Series D non-voting convertible preferred stock, but before any proceeds are distributed to the holders of common stock, the Series C-2 non-voting convertible preferred stock. The Series E non-voting convertible preferred stock ranks senior to the Company’s common stock; senior to any class or series of capital stock created after the issuance of the Series E non-voting preferred stock; senior to the Series C-2 and the Series C-3 non-voting convertible preferred stock; on parity with the Series D non-voting convertible preferred stock; and junior to the Series F non-voting convertible preferred stock. As long as any of the Series E non-voting convertible preferred stock is outstanding, the Company cannot, without the consent of a majority of the Series E holders, incur any indebtedness other than indebtedness existing prior to September 15, 2014, trade payables incurred in the ordinary course of business consistent with past practice, and letters of credit incurred in an aggregate amount of $3.0 million at any point in time. In addition to the debt restrictions above, as long as any the Series E non-voting convertible preferred stock is outstanding , the Company cannot, among others things: create, incur, assume or suffer to exist any encumbrances on any of our assets or property; redeem, repurchase or pay any cash dividend or distribution on any of our capital stock (other than as permitted); redeem, repurchase or prepay any indebtedness; or engage in any material line of business substantially different from our current lines of business. In the event the Company issues any options, convertible securities or rights to purchase stock or other securities pro rata to the holders of common stock, then holders of Series E non-voting convertible preferred stock will be entitled to acquire, upon the same terms a pro rata amount of such stock or securities as if the Series E non-voting convertible preferred stock had been converted to common stock. Stock Options: The Company’s 2013 Stock Incentive Plan (the “2013 Plan”) was approved by the shareholders in July 2013. The 2013 Plan provides for the issuance of equity grants in the form of options, restricted stock, stock awards and other forms of equity compensation. Awards under the 2013 Plan may be made to directors, officers, employees and consultants under the 2013 Plan. Initially, an aggregate of 5,000,000 shares of the Company’s common stock was reserved for issuance under the 2013 Plan. On January 19, 2016, the shareholders approved an increase of the shares issuable under the 2013 Plan from 5,000,000 to 8,000,000 and on June 13, 2016 from 8,000,000 to 11,000,000. During the year ended December 31, 2018, the Company granted ten-year qualified and non-qualified stock options to its officers, directors, employees and consultants covering an aggregate of 678,000 shares of the Company’s common stock under the 2013 Stock Incentive Plan. The weighted average exercise price of these options are $0.44 per share. During the years ended December 31, 2018 and 2017, total compensation expense for stock options issued to employees, directors, officers and consultants was $1,018,000 and $1,571,000, respectively. As of December 31, 2018, there was $1,619,000 total unrecognized compensation expense related to stock options granted which expense will be recognized over an expected remaining weighted average period of 1.33 years. All share-based awards are recognized on a straight-line method, assuming all awards granted will vest. Forfeitures of share-based awards are recognized in the period in which they occur. The fair value at grants dates of the grants issued subject to service and performance based vesting conditions were determined using the Black-Scholes option pricing model with the following assumptions: Year Ended December 31, 2018 2017 Risk-free interest rate 2.63% - 2.96% 1.77% - 2.40% Expected volatility 93% - 103% 95% - 106% Expected term (years) 5 years 5 - 10 years Expected dividend yield 0.0% 0.0% Weighted-average grant date fair value of options granted during the period $ 0.32 $ 1.18 The Company estimated the expected term of the stock options granted based on anticipated exercises in future periods. The expected term of the stock options granted to consultants is based upon the full term of the respective option agreements. The expected stock price volatility for the Company’s stock options is calculated based on the historical volatility since the initial public offering of the Company’s common stock in March 2010. The expected dividend yield of 0.0% reflects the Company’s current and expected future policy for dividends on the Company’s common stock. To determine the risk-free interest rate, the Company utilized the U.S. Treasury yield curve in effect at the time of grant with a term consistent with the expected term of the Company’s awards which is 5 years for employees and 10 years for non-employees. The following table summarizes the Company’s stock options activity and related information for the year ended December 31, 2018: Shares Underlying Stock Options Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Outstanding at beginning of year 4,962,795 $ 2.04 7.5 $ 247,500 Granted 678,000 $ 0.44 572,610 Exercised (40,000 ) $ 0.29 42,400 Expired/Cancelled (90,531 ) $ 1.35 21,912 Forfeited (453,938 ) $ 1.89 113,348 Outstanding at end of year 5,056,326 $ 1.86 6.7 $ 1,006,743 Vested at end of year 3,478,053 $ 1.88 6.1 $ 639,369 Expected to vest in the future 1,578,273 $ 1.82 8.2 $ 367,374 The total intrinsic value of stock options exercised during the years ended December 31, 2018 and 2017 was $42,400 and $13,200, respectively. The aggregate intrinsic value is calculated as the difference between the exercise prices of the underlying options and the quoted closing price of the common stock of the Company at the end of the reporting period for those options that have an exercise price below the quoted closing price. Warrants: The following table is the summary of warrant activities: Shares Underlying Warrants Weighted Average Exercise Price Weighted Average Remaining Contractual Life Outstanding at December 31, 2017 23,417,891 $ 1.08 3.4 Issued 450,000 1.50 5.0 Exercised (2,442,376 ) 1.05 - Expired (4,830,499 ) 0.87 - Outstanding at December 31, 2018 16,595,016 $ 1.10 3.1 On December 31, 2018, the Company sold to Elliott a senior secured convertible note in the aggregate principal amount of $7,500,000 and a warrant to purchase up to an aggregate of 450,000 shares of common stock, for gross proceeds of $7,500,000. The warrant is immediately exercisable, has an exercise price of $1.50 per share, subject to adjustment in the event of stock dividends and distributions, stock splits, stock combinations, or reclassifications affecting the Company’s common stock, and has a term of five years (see Note 6). On December 31, 2018, the Company amended and restated the following warrants held by Elliott and its affiliates to reduce the exercise price of each warrant to $0.001 per share: warrants issued in May 2013 to purchase up to an aggregate of 500,000 shares of the Company’s common stock with a pre-amendment exercise price of $0.65 per share and an expiration date of May 30, 2019 (the “May 30, 2019 Warrants”); and warrants issued in October 2013 to purchase up to an aggregate of 750,000 shares of common stock with a pre-amendment exercise price of $0.90 per share and an expiration date of October 22, 2019 (the “October 22, 2019 Warrants”). The incremental cost of approximately $710,000 associated with the warrant modification was recorded as a debt discount. The fair value of the warrant was determined using a Black-Scholes option pricing model using the following assumptions at the grant date of the warrant: December 31, 2018 Expected Term 5.0 years Volatility 102.85 % Dividend yield 0.0 % Exercise Price $ 1.50 Risk-free interest rate 2.51 % On November 9, 2017, in addition to the securities purchase agreement issued to Elliott (See Note 8 Preferred Stock), the Company entered into a backstop agreement with Elliott to purchase additional Series F convertible preferred Stock at $1,000 per share, at the Company’s sole discretion, beginning January 15, 2018 through March 31, 2018. As consideration for the backstop agreement, the Company issued 564,858 warrants, exercisable for three years, to purchase shares of the Company’s common stock at a per share exercise price of $0.001. The number of shares issuable under the warrant was determined by the closing price of the Company’s common stock on November 8, 2017, which was $0.5278, reduced by the amount of equity capital raised from the ATM program and the sale of common stock to directors, executive officers and other certain employees of the Company totaling $2.4 million. On November 16, 2017, the Company recorded a derivative liability of $270,592 and a corresponding reduction to additional paid in capital based on the initial Black Scholes valuation. The warrants were initially classified as a liability as the Company had a conditional obligation to settle the warrants by issuing a variable number of shares with variations of the obligation based on inputs other than the fair value of the Company’s shares (i.e. the amount subject to the backstop agreement). The fair value of the warrants was determined using a Black-Scholes option pricing model using the following assumptions at the grant date of the warrants: November 16, 2017 Expected Term 3.0 years Volatility 98 % Dividend yield 0.0 % Exercise Price $ 0.00 Risk-free interest rate 1.83 % Fair value of warrants granted $ 270,592 Number of shares underlying warrants granted 564,858 On December 24, 2017, the derivative liability of $327,079 was reclassified to equity as the number of issued warrants was determined on that date. Prior to the reclassification to equity, an expense of $56,487 for the change in fair value of derivative liability was recorded on the Company’s consolidated statement of operations and comprehensive income (loss) for the year ended December 31, 2017, which represented the increase in the fair value of the derivative liability from November 16, 2017, the original valuation date of the warrants, and December 24, 2017, the date the warrants became classified as equity. As these warrants were liability-classified prior to the reclassification to equity, the fair value of the warrants were revalued at December 24, 2017 using the following assumptions: December 24, 2017 Expected Term 2.90 years Volatility 98 % Dividend yield 0.0 % Exercise Price $ 0.00 Risk-free interest rate 2.01 % Weighted average fair value of warrants granted $ 327,079 Number of shares underlying warrants granted 564,858 In the May 2017 public offering, the Company issued 29,046,110 warrants, of which 9,886,250 warrants were subsequently exchanged for 2,471,561 shares of the Company's common stock during the year ended December 31, 2017. In the May 2017 public offering, the Company did not have sufficient number of authorized shares of common stock available to reserve the shares issuable upon the exercise of 29,046,110 outstanding warrants issued in the May 2017 public offering. Therefore, these warrants were classified as liabilities at June 30, 2017 and were re-measured on August 10, 2017, which was the Exercisable Date, with any increase or decrease in value recorded as a loss or gain in the income statement. The Company recorded a loss of $1,974,019 during the year ended December 31, 2017. As of August 9, 2017, the Company had enough authorized shares to cover the issuance of these warrants, and therefore the derivative liability was reclassified to equity on that date in the amount of $3,854,195. The fair value of the warrants was determined using a probability-weighted Black-Scholes option pricing under different scenarios regarding the expected probability and timing of sufficient additional shares being authorized to allow the warrants to become exercisable. The following assumptions were used to value the warrants at the grant date. Series A Series B Underwriter’s Expected Term 1.18 – 1.33 years 5.10 – 5.25 years 5.10 – 5.25 years Volatility 55% 55% 55% Dividend yield 0.0% 0.0% 0.0% Exercise Price $0.75 $1.05 $0.94 Risk-free interest rate 1.13% - 1.16% 1.86% - 1.88% 1.86% - 1.88% Weighted average fair value of warrants granted $0.08 $0.17 $0.18 Number of shares underlying warrants granted 13,964,476 13,964,476 1,117,158 As these warrants are liability-classified, they were revalued at August 10, 2017 using the following assumptions: Series A Series B Underwriter’s Expected Term 1.09 5.00 5.00 Volatility 96.95% 96.95% 96.95% Dividend yield 0.0% 0.0% 0.0% Exercise Price $ 0.75 $ 1.05 $ 0.94 Risk-free interest rate 1.22% 1.76% 1.76% Weighted average fair value of warrants $ 0.06 $ 0.20 $ 0.20 Various warrants that the Company has issued contain a prohibition on the Company entering into a merger, sale of all or substantially all of its assets or similar transaction unless the acquiring entity assumes all of the obligations of the Company under the warrants and also is a publicly traded corporation whose common stock is quoted on or listed for trading on a securities exchange, provided that this prohibition will not apply to an all cash acquisition. Stock-based Deferred Compensation Plan for Non-Employee Directors During the third quarter of 2014, the Company established an unfunded stock-based deferred compensation plan, providing non-employee directors the opportunity to defer up to one hundred percent of fees and compensation, including restricted stock units. The amount of fees and compensation deferred by a non-employee director is converted into stock units, the number of which is determined based on the closing price of the Company’s common stock on the date such compensation would have otherwise been payable. At all times, the plan participants are one hundred percent vested in their respective deferred compensation accounts. On the tenth business day of January in the year following a director’s termination of service, the director will receive a number of common shares equal to the number of stock units accumulated in the director’s deferred compensation account. The Company accounts for this plan as stock based compensation under ASC 718. During the year ended December 31, 2018 and 2017, the amount of compensation that was deferred under this plan was $30,000 and $57,940, respectively. |