The Company issued shares of redeemable preferred stock in connection with its initial public offering in June 2006. As of December 31, 2018 and 2017, the redeemable preferred stock carrying value was $23.6 million and there were 20 million shares of redeemable preferred stock authorized. The redeemable preferred stock is not convertible into common stock but is redeemable at $9.00 per share, (i) upon the Company’s liquidation, dissolution or winding up, or the occurrence of certain mergers, consolidations or sales of all or substantially all of the Company’s assets, before any payment to the holders of the Company’s common stock, or (ii) at the Company’s option at any time. Holders of redeemable preferred stock are generally not entitled to vote on matters submitted to the stockholders, except with respect to certain matters that will affect them adversely as a class, and are not entitled to receive dividends. The carrying value of the redeemable preferred stock was $7.11 per share at December 31, 2018 and 2017. The redeemable preferred stock is presented separately from stockholders’ deficit in the consolidated balance sheets and any adjustments to its carrying value up to its redemption value of $9.00 per share are reported as a dividend.

In March 2017, the Company completed a private placement (the “2017 Private Placement”) with certain institutional and accredited investors, including certain directors, executive officers and employees of the Company (collectively, the “Purchasers”), providing for the sale by the Company of 1,809,628 shares of the Company’s common stock at a purchase price of $2.00 per share and 15,245 shares of newly designated Series A Convertible Preferred Stock at a purchase price of $1,000 per share (which shares were convertible into approximately 7,622,372 shares of common stock).

The 2017 Private Placement generated aggregate gross proceeds to the Company of approximately $18.9 million. The Series A Convertible Preferred Stock are entitled to dividends on an as-if-converted basis in the same form as any dividends actually paid on shares of common stock or other securities. Except as otherwise required by law, the holders of Series A Convertible Preferred Stock have no right to vote on matters submitted to a vote of the Company’s stockholders. Without the prior written consent of 75% of the outstanding shares of Series A Convertible Preferred Stock, the Company may not: (a) alter or change adversely the powers, preferences or rights given to the Series A Convertible Preferred Stock or alter or amend the Certificate of Designation for the Series A Convertible Preferred Stock, (b) amend the Company’s certificate of incorporation or other charter documents in any manner that adversely affects any rights of the holders of Series A Convertible Preferred Stock, (c) increase the number of authorized shares of Series A Convertible Preferred Stock, or (d) enter into any agreement with respect to any of the foregoing. In the event of the dissolution and winding up of the Company, the proceeds available for distribution to the Company’s stockholders shall be distributed pari passu among the holders of the shares of common stock and Series A Convertible Preferred Stock, pro rata based upon the number of shares held by each such holder, as if the outstanding shares of Series A Convertible Preferred Stock were convertible, and were converted, into shares of common stock.

During the years ended December 31, 2018 and 2017, 1,274 and 9,927 shares of Series A Preferred Stock were converted into 636,997 and 4,963,702 shares of common stock. As of December 31, 2018, there were 4,043 shares of Series A Convertible Preferred Stock outstanding, which are convertible into 2,021,673 shares of common stock. See Note 16 for information regarding Series A conversions that occurred during the first quarter of 2019.

In connection with the 2017 Private Placement, the Company issued warrants to purchase up to 9,432,000 shares of the Company’s common stock at an exercise price of $2.00 per share (the “2017 Common Stock Warrants”). The Company also issued warrants to purchase common stock to the exclusive placement agents for the issuance (“the 2017 Banker Warrants”). The 2017 Banker Warrants were for the purchase of up to an aggregate of 471,600 shares of the Company’s common stock with substantially the same terms as the 2017 Common Stock Warrants, except that they have an exercise price equal $2.50 per share.

The 2017 Common Stock Warrants and the 2017 Banker Warrants (collectively, the “2017 Warrants”) expire on June 15, 2022.

The 2017 Warrants, are exercisable for cash. The exercise price is subject to adjustment in the case of stock dividends or other distributions on shares of common stock or any other equity or equity equivalent securities payable in shares of common stock, stock splits, stock combinations, reclassifications or similar events affecting the Company’s common stock, and also, subject to limitations, upon any distribution of assets, including cash, stock or other property to the Company’s stockholders.

Prior to exercise, holders of the 2017 Warrants do not have any of the rights of holders of the common stock purchasable upon exercise, including voting rights; however, the holders of the 2017 Warrants have certain rights to participate in distributions or dividends paid on the Company’s common stock to the extent set forth in the respective warrant agreements.

The 2017 Warrants may not be exercised by the holder to the extent that the holder, together with its affiliates, would beneficially own, after such exercise more than 4.99% of the shares of the Company’s common stock then outstanding (subject to the right of the holder to increase or decrease such beneficial ownership limitation upon notice to us, provided that such limitation cannot exceed 9.99%) and provided that any increase in the beneficial ownership limitation shall not be effective until 61 days after such notice is delivered.

If the Company effects a fundamental transaction, then upon any subsequent exercise of any 2017 Warrants, the holder thereof shall have the right to receive, for each share of common stock that would have been issuable upon such exercise immediately prior to the occurrence of such fundamental transaction, the number of shares of the successor’s or acquiring corporation’s common stock or of the Company’s common stock, if the Company is the surviving corporation, and any additional consideration receivable as a result of such fundamental transaction by a holder of the number of shares of common stock into which the 2017 Warrants were exercisable immediately prior to such fundamental transaction. In addition, in the event of a fundamental transaction (other than a fundamental transaction not approved by the Company’s Board of Directors), the Company or any successor entity shall, at the holder’s option, purchase the holder’s 2017 Warrants for an amount of cash equal to the value of the 2017 Warrants as determined in accordance with the Black Scholes option pricing model. A fundamental transaction as described in the 2017 Warrants generally includes any merger with or into another entity, sale of all or substantially all of the Company’s assets, tender offer or exchange offer, reclassification of the Company’s common stock or the consummation of a transaction whereby another entity acquires more than 50% of the Company’s outstanding voting stock.

Based on the terms of the 2017 Warrants, the Company may be required to settle such warrants with cash upon a fundamental transaction, as defined. Since potential future cash settlement is deemed to be within the Company’s control, the 2017 Warrants are classified in stockholders’ equity in accordance with the authoritative accounting guidance.

In conjunction with the 2018 Private Placement described further below, a holder of 2.4 million 2017 Warrants exercised all of its 2017 Warrants at the original exercise price of $2.00 per warrant in exchange for the issuance of additional warrants. As a result of the warrant exercise, the Company received gross proceeds of $4.8 million during the year ended December 31, 2018.

During the year ended December 31, 2018, excluding the $4.8 million described above, the Company received proceeds of approximately $4.0 million in connection with the exercise of approximately 1.9 million of 2017 Common Stock Warrants. During the year ended December 31, 2017, the Company received proceeds of approximately $3.3 million in connection with the exercise of approximately 1.7 million of Common Stock Warrants. As of December 31, 2018, there were 3,757,000 shares of 2017 Common Stock Warrants outstanding.

During the year ended December 31, 2018, 304,182 of the 2017 Banker Warrants were exercised for total cash proceeds upon exercise of $0.8 million during the period. No 2017 Banker Warrants were exercised during the year ended December 31, 2017. A total of 167,418 of the 2017 Banker Warrants remained outstanding as of December 31, 2018.

On March 8, 2018, the Company completed the 2018 Private Placement to certain institutional and accredited investors, including certain directors and executive officers of the Company, providing for the sale by the Company at a purchase price of $1,000 per share, 45,200 of newly designated Series B Convertible Preferred Stock, which shares of preferred stock were automatically converted into 14,349,236 shares of the Company’s common stock upon approval by the Company’s stockholders at the 2018 annual meeting of stockholders held in May 2018, and warrants to purchase up to 12,196,851 shares of common stock at an exercise price of $3.50 per share (the “2018 Common Stock Warrants”). The 2018 Common Stock Warrants became exercisable following stockholder approval at the 2018 annual meeting of stockholders, are subject to certain ownership limitations in certain cases, and expire five years after the date of such stockholder approval. The gross proceeds from the 2018 Private Placement were approximately $45.2 million.

Pursuant to the terms of the purchase agreement entered into in connection with the 2018 Private Placement, from the date of the stockholder approval of the 2018 Private Placement, or May 17, 2018, through the first anniversary of the effective date of the resale registration statement related to the 2018 Private Placement, or May 11,2019, if the Company issues any shares of common stock or common stock equivalents, subject to certain permitted exceptions, at a price below the conversion price on the date stockholder approval was obtained (a “Dilutive Issuance”), the Company is required to issue an additional number of shares of common stock to the purchasers in the 2018 Private Placement in amount equal the number of shares of common stock such purchasers would have received if the Dilutive Issuance occurred prior to the date the Company’s stockholders approved the 2018 Private Placement.

The 2018 Common Stock Warrants (the “2018 Warrants”), are exercisable for cash or by cashless exercise. The exercise price of the 2018 Warrants is subject to adjustment in the case of stock dividends or other distributions on shares of common stock or any other equity or equity equivalent securities payable in shares of common stock, stock splits, stock combinations, reclassifications or similar events affecting the Company’s common stock, and also, subject to limitations, upon any distribution of assets, including cash, stock or other property to the Company’s stockholders.

Prior to the exercise, holders of the 2018 Warrants do not have any of the rights of holders of the common stock purchasable upon exercise, including voting rights; however, the holders of the 2018 Warrants have certain rights to participate in distributions or dividends paid on the Company’s common stock to the extent set forth in the 2018 Warrants.

Some of the 2018 Warrants may not be exercised by the holder to the extent that the holder, together with its affiliates, would beneficially own, after such exercise more than 4.99% of the shares of the Company’s common stock then outstanding (subject to the right of the holder to increase or decrease such beneficial ownership limitation upon notice to us, provided that such limitation cannot exceed 9.99%) and provided that any increase in the beneficial ownership limitation shall not be effective until 61 days after such notice is delivered.

If the Company effects a fundamental transaction, then upon any subsequent exercise of any 2018 Warrants, the holder thereof shall have the right to receive, for each share of common stock that would have been issuable upon such exercise immediately prior to the occurrence of such fundamental transaction, the number of shares of the successor’s or acquiring corporation’s common stock or of the Company’s common stock, if the Company is the surviving corporation, and any additional consideration receivable as a result of such fundamental transaction by a holder of the number of shares of common stock into which the 2018 Warrants were exercisable immediately prior to such fundamental transaction. A fundamental transaction as described in the 2018 Warrants generally includes any merger with or into another entity, sale of all or substantially all of the Company’s assets, tender offer or exchange offer, reclassification of the Company’s common stock or the consummation of a transaction whereby another entity acquires more than 50% of the Company’s outstanding voting stock.

In addition to the 12,196,851 warrants issued in the 2018 Private Placement, the Company issued 1,800,000 warrants to an existing holder with identical terms to the 2018 Warrants, including the exercise price of $3.50.

All the 2018 Warrants were deemed to qualify for equity classification under authoritative accounting guidance.

	Number of Warrants		Strike Price
2017 Common Stock Warrants		3,757,000	$	2.00
2017 Banker Warrants		167,418	$	2.50
2018 Common Stock Warrants		13,996,851	$	3.50
Merger Warrants		2,200,000	$	3.50
Executive		1,327,434	$	5.00
Squadron Capital		845,000	$	3.15
Other		7,812	$	19.20
Total		22,301,515

In December 2011, in connection with the third amendment to the Company’s former credit facility with the Silicon Valley Bank ("SVB"), finance charges totaling $0.2 million were waived in exchange for the issuance to SVB of warrants to purchase 7,812 shares of the Company’s common stock. The warrants are immediately exercisable, can be exercised through a cashless exercise, have an exercise price of $19.20 per share and have a 10-year term.

As mentioned above, the Company issued Common Stock Warrants in connection with the private placement financing in March 2017 and March 2018. The warrants expire on the fifth anniversary of the date on which they were first exercisable. Further, as described in Note 8, the Company issued warrants in conjunction with the acquisition of SafeOp.

In December 2017 the Company issued warrants to Mr. Miles, the Company’s Chairman and Chief Executive Officer, to purchase 1,327,434 shares of the Company’s common stock for $5 per share. The warrants have a five-year term. The warrants issued to Mr. Miles were accounted for as share based compensation, and the fair value of the warrants of approximately $1.4 million were recognized in full in the statement of operations for the year ended December 31, 2017 as the warrants were immediately vested upon issuance. The following inputs were used to estimate the fair value of warrants issued to Mr. Miles: risk free interest rate of 1.9%, volatility of 99.5%, expected term of 2.3 years and dividend yield of 0%.

As further described in Note 5, in connection with the debt financing with Squadron, the Company issued warrants to purchase 845,000 shares of common stock at an exercise price of $3.15 per share. The warrants have a seven-year term and are immediately exercisable. In accordance with authoritative accounting guidance, the warrants classified for equity treatment upon issuance and were recorded as a debt discount to the face of the debt liability based on a relative fair value basis to be amortized into interest expense over the life of the debt agreement. As the warrants provide for partial price protection that allow for a reduction in the price in the event of a lower per share priced issuance, the warrants were valued utilizing a Monte Carlo simulation that considers the probabilities of future financings. The Monte Carlo model simulates the present value of the potential outcomes of future stock prices of the Company over the seven-year life of the warrants. The projection of stock prices is based on the risk-free rate of return and the volatility of the stock price of the Company and correlates future equity raises based on the probabilities provided.