Redeemable Preferred Stock	12 Months Ended
Dec. 31, 2016
Redeemable Preferred Stock
Redeemable Preferred Stock	13. Redeemable Preferred Stock In December 2016, the Company completed an offering of an aggregate of 18,500 shares of the Company’s Series D Redeemable Preferred Stock, par value $0.01 per share and warrants to purchase 7,381,500 shares of common stock. The net proceeds to the Company were approximately $15.6 million, after deducting underwriting discounts and commissions and estimated expenses payable by the Company. The terms and conditions of the warrants issued pursuant to the preferred share offering are identical to the warrants issued pursuant to the common share offering (see Note 12, Stockholders’ Equity). The Company is required to redeem the Series D Redeemable Preferred Stock in ten monthly installments in the amount of $1.9 million each from January 2017 through October 2017. Each share of Series D Redeemable Preferred Stock was issued with an initial stated value of $1,000 per share. Over the first ten months of 2017, the Series D Redeemable Preferred Stock will be redeemed in ten equal installments of $1.9 million. The Company is required to elect, on a monthly basis, whether it will redeem or convert the required installment. Should the Company elect to redeem, the shares are valued at the stated value. Should the Company elect to convert, the holder of the shares will receive common stock, with a conversion price discounted at 12% of market value. Also, the holders of the shares, at any time, may elect to convert all or any whole amount of shares, using a conversion price of $1.55. Conversion prices become more discounted upon a change in control, remote triggering events, or failure to make a redemption payment. Except for our Series C Redeemable Preferred Stock, which shall rank senior to the Series D Redeemable Preferred Stock as to dividends, distributions and payments upon the Company’s liquidation, dissolution and winding up, and subject to the issuance of capital stock that is of senior or pari-passu rank to the preferred shares, all shares of our capital stock, including our common stock, shall be junior in rank to all preferred shares with respect to dividends, distributions and payments upon our liquidation, dissolution and winding up or any capital stock that has a maturity date or other date requiring redemption or repayment prior to the maturity date of the preferred stock. Holders of the Series D Redeemable Preferred Shares are not entitled to receive dividends except in connection with certain purchase rights and other corporate events, as described in the certificate of designations, or in connection with certain distributions of assets, as described in the certificate of designations, or as, when and if declared by the Company’s Board of Directors acting in its sole and absolute discretion. Holders of Series D Redeemable Preferred Shares shall have no voting rights, except on matters required by law or under the certificate of designations to be submitted to a class vote of the holders of the Series D Redeemable Preferred Shares. On May 8, 2013, the Company entered into a Securities Purchase Agreement with Air Liquide, pursuant to which the Company agreed to issue and sell 10,431 shares of the Company’s Series C Redeemable Preferred Stock. On August 26, 2014, Air Liquide acquired 5,521,676 shares of Common Stock by converting 5,200 shares of Series C Redeemable Preferred Stock at the conversion price of $0.2343. Following the conversion, Air Liquide continues to own 5,231 shares of Series C Redeemable Preferred Stock. The holder of these shares is entitled to designate one director to the Company’s Board of Directors. In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company, or other deemed liquidation event, as defined in the Securities Purchase Agreement, the holder of the Series C Redeemable Preferred Stock will be entitled to be paid an amount per share equal to the greater of (i) the original issue price, plus any accrued but unpaid dividends or (ii) the amount per share that would have been payable had all shares of the Series C Redeemable Preferred Stock been converted to shares of common stock immediately prior to such liquidation event. The Series C Redeemable Preferred Stock is redeemable at the election of the holder of the Series C Redeemable Preferred Stock or the Company. The holder of the Series C Redeemable Preferred Stock is entitled to receive dividends at a rate of 8% per annum, based on the original issue price of $2,595,400, payable in equal quarterly installments in cash or in shares of Common Stock, at the Company’s option. During the years ended December 31, 2016, 2015 and 2014 dividends have been paid in the form of shares of Common Stock. The Series C Redeemable Preferred Stock is convertible into shares of Common Stock with the number of shares of Common Stock issuable upon conversion determined by dividing the original issue price of $2,595,400 by the conversion price in effect at the time the shares are converted. The conversion price of the Series C Redeemable Preferred Stock as of December 31, 2016 and 2015 was $0.2343. The Series C Redeemable Preferred Stock votes together with the Common Stock on an as-converted basis on all matters.

13. Redeemable Preferred Stock

In December 2016, the Company completed an offering of an aggregate of 18,500 shares of the Company’s Series D Redeemable Preferred Stock, par value $0.01 per share and warrants to purchase 7,381,500 shares of common stock. The net proceeds to the Company were approximately $15.6 million, after deducting underwriting discounts and commissions and estimated expenses payable by the Company. The terms and conditions of the warrants issued pursuant to the preferred share offering are identical to the warrants issued pursuant to the common share offering (see Note 12, Stockholders’ Equity). The Company is required to redeem the Series D Redeemable Preferred Stock in ten monthly installments in the amount of $1.9 million each from January 2017 through October 2017.

Each share of Series D Redeemable Preferred Stock was issued with an initial stated value of $1,000 per share. Over the first ten months of 2017, the Series D Redeemable Preferred Stock will be redeemed in ten equal installments of $1.9 million. The Company is required to elect, on a monthly basis, whether it will redeem or convert the required installment. Should the Company elect to redeem, the shares are valued at the stated value. Should the Company elect to convert, the holder of the shares will receive common stock, with a conversion price discounted at 12% of market value. Also, the holders of the shares, at any time, may elect to convert all or any whole amount of shares, using a conversion price of $1.55. Conversion prices become more discounted upon a change in control, remote triggering events, or failure to make a redemption payment.

Except for our Series C Redeemable Preferred Stock, which shall rank senior to the Series D Redeemable Preferred Stock as to dividends, distributions and payments upon the Company’s liquidation, dissolution and winding up, and subject to the issuance of capital stock that is of senior or pari-passu rank to the preferred shares, all shares of our capital stock, including our common stock, shall be junior in rank to all preferred shares with respect to dividends, distributions and payments upon our liquidation, dissolution and winding up or any capital stock that has a maturity date or other date requiring redemption or repayment prior to the maturity date of the preferred stock.

Holders of the Series D Redeemable Preferred Shares are not entitled to receive dividends except in connection with certain purchase rights and other corporate events, as described in the certificate of designations, or in connection with certain distributions of assets, as described in the certificate of designations, or as, when and if declared by the Company’s Board of Directors acting in its sole and absolute discretion. Holders of Series D Redeemable Preferred Shares shall have no voting rights, except on matters required by law or under the certificate of designations to be submitted to a class vote of the holders of the Series D Redeemable Preferred Shares.

On May 8, 2013, the Company entered into a Securities Purchase Agreement with Air Liquide, pursuant to which the Company agreed to issue and sell 10,431 shares of the Company’s Series C Redeemable Preferred Stock. On August 26, 2014, Air Liquide acquired 5,521,676 shares of Common Stock by converting 5,200 shares of Series C Redeemable Preferred Stock at the conversion price of $0.2343. Following the conversion, Air Liquide continues to own 5,231 shares of Series C Redeemable Preferred Stock. The holder of these shares is entitled to designate one director to the Company’s Board of Directors. In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company, or other deemed liquidation event, as defined in the Securities Purchase Agreement, the holder of the Series C Redeemable Preferred Stock will be entitled to be paid an amount per share equal to the greater of (i) the original issue price, plus any accrued but unpaid dividends or (ii) the amount per share that would have been payable had all shares of the Series C Redeemable Preferred Stock been converted to shares of common stock immediately prior to such liquidation event. The Series C Redeemable Preferred Stock is redeemable at the election of the holder of the Series C Redeemable Preferred Stock or the Company.

The holder of the Series C Redeemable Preferred Stock is entitled to receive dividends at a rate of 8% per annum, based on the original issue price of $2,595,400, payable in equal quarterly installments in cash or in shares of Common Stock, at the Company’s option. During the years ended December 31, 2016, 2015 and 2014 dividends have been paid in the form of shares of Common Stock. The Series C Redeemable Preferred Stock is convertible into shares of Common Stock with the number of shares of Common Stock issuable upon conversion determined by dividing the original issue price of $2,595,400 by the conversion price in effect at the time the shares are converted. The conversion price of the Series C Redeemable Preferred Stock as of December 31, 2016 and 2015 was $0.2343. The Series C Redeemable Preferred Stock votes together with the Common Stock on an as-converted basis on all matters.