
	December 31,
	2019		2018

Convertible Note, at fair value	$	39,020,000	$	—

Marathon Tranche I Loan	—		10,000,000
Marathon Credit Agreement unamortized debt discount and issuance costs	—		(1,687,921)
Net Marathon Credit Agreement	—		8,312,079
Total long-term debt	39,020,000		8,312,079
Less current portion	19,620,000		—
Long-term debt, net of current portion	$	19,400,000	$	8,312,079

The amounts in the aggregate maturities table only include the par value of the Convertible Note to be repaid and does not include the additional 12% premium described below. The 2019 year includes the remaining $4.5 million the Company is required to convert by April 2020 and all of the Redemption Payments (described below).

The current portion of the Convertible Note includes the remaining $4.5 million required to be converted through April 1, 2020, as well as the Redemption Payment (described below) due in 2020.

On December 9, 2019, the Company issued a $41.0 million par value Convertible Note (the "Convertible Note") due November 2022, with a stated interest rate of 4.50% per annum. The Company has elected to account for the Convertible Note using the fair value option allowed under GAAP. The fair value of the Convertible Note was $38.5 million on December 9, 2019. The Convertible Note was issued at 95% of par. Interest is payable quarterly beginning February 1, 2020. The Convertible Note is initially convertible at a rate of $3.05 per share subject to change for anti-dilution adjustments or certain corporate events.

The Company is required to convert a minimum of $5.0 million of the Convertible Note for the period by April 1, 2020. During the year ended December 31, 2019, $0.5 million par value of the Convertible Note was converted into 185,186 shares of common stock resulting in a gain of $83,089, which is included in Interest Expense. Subsequent to December 31, 2019, an additional $4.5 million par value of the Convertible Note was converted into 1,546,889 shares of common stock.

As of December 31, 2019, the fair value of the Convertible Note was $39.0 million and the contractual principal balance was $40.5 million. In electing the fair value option, the Company recognizes changes in fair value related to changes in credit risk, if any, in Other Comprehensive Income and the remaining change in fair value in Interest Expense. For the year ended December 31, 2019, the fair value of the Convertible Note increased $1.0 million which is included in Interest Expense. No portion of the change in fair value was related to changes in credit risk for the period.

Any principal repayment of the Convertible Note is at 112% of the par value. Beginning March 1, 2020 the holder of the Convertible Note may require the Company to redeem up to $1.5 million par value ("Redemption Payment") of the Convertible Note monthly. Subject to certain limitations, the Company at its discretion can pay some or all of Redemption Payment in cash or shares of common stock.

The Convertible Note is a senior secured obligation of the Company secured by substantially all assets of the Company and rank senior to all unsecured debt of the Company. The Convertible Note contains certain covenants, including that we maintain at all times liquidity calculated as unrestricted, unencumbered cash and cash equivalents in a minimum amount of $8.0 million.

The primary reason for electing the fair value option is for simplification and cost-benefit considerations of accounting for the Convertible Note (the hybrid financial instrument) at fair value in its entirety versus bifurcation of the embedded derivatives. The significant inputs to the valuation of the Convertible Note at fair value are Level 3 inputs since they are not observable directly. The fair value was determined using a binomial lattice valuation model, which is widely used for valuing convertible notes. The significant assumptions used in the model are the credit spread and volatility of the Company's common stock.

The Convertible Note was issued with 15,459,016 warrants to purchase common stock of the Company. The exercise price is the greater of the conversion price of the Convertible Note on the day the warrants become exercisable or the weighted average 30 day price of our common stock. The initial exercise price was $3.05 per share. The warrants are only exercisable at the option of the Company following the full or partial redemption of the Convertible Note. The Convertible Note and the warrants were determined to be freestanding instruments and were accounted for separately. The warrants are classified as equity instruments and the fair value has been estimated to be $0.4 million on December 9, 2019 and recorded as an increase to Additional Paid-In Capital.

On December 31, 2018, the Company entered into a Credit Agreement (the “Credit Agreement”), with Marathon Asset Management, LP, on behalf of certain entities it manages (collectively, the “Lenders”). The Credit Agreement provided the Company with $10 million of term loans (the “Tranche One Loans”) and $25 million of revolving term loans (the Tranche Two Loans together with the Tranche One Loans, the “Loans”).

In conjunction with entering into the Credit Agreement, the Company issued a Common Stock Purchase Warrant to purchase 8,053,390 shares of common stock at an exercise price of $1.25 per share (the “Initial Warrants”). Until December 31, 2020 even after the payoff of the Loans, the Company is required to issue additional Common Stock Purchase Warrants (the “Additional Warrants”) to the Lenders equal to 10%, in the aggregate, of any additional issuance. The initial exercise price is 110% of the issuance price of the applicable issuance.

The Marathon Credit Agreement and Initial Warrants were determined to be freestanding instruments and were accounted for separately. The Initial Warrants do not qualify for equity classification and have been classified as liability instruments. The value of the Initial Warrants on the date of the Credit Agreement was estimated to be $965,747 which was determined using the Black-Scholes valuation model and was recorded as a liability with the offset being recorded as a debt discount. The liability for the Initial Warrants are marked-to-market quarterly in accordance with liability accounting with a corresponding charge to Interest Expense.

The closing costs associated with the Marathon Credit Agreement were allocated based on proportional value to the Tranche One Loan, Tranche Two Loan and the Initial Warrants. Costs of $722,174 allocated to Tranche 1 were recorded as a debt discount; costs of $1,830,435 allocated to Tranche 2 were recorded as a prepaid asset and were amortized over the expected life of the loan; and costs of $69,744 allocated to the Initial Warrants were expensed in the year ended December 31, 2018.

As of December 31, 2019 and 2018, the liability for the Initial Warrants was $16,335,000 and $965,747, respectively. Any additional warrants issued in connection with the Credit Agreement are classified as equity instruments and are not marked-to-market at each balance sheet date as they do not include the features of the Initial Warrants that required liability accounting.

A loss on extinguishment of approximately $6.1 million was recognized on the payoff of the Marathon Loans and is recorded within Interest Expense in the accompanying Consolidated Statements of Operations for the year ended December 31, 2019. The loss on extinguishment includes a $3.4 million premium which was payable on the early payoff of the Marathon Loans.

In 2018, the Company entered into a $7.8 million term loan with a fund managed by Arosa (the “Arosa Loan”). The interest rate for the Arosa Loan was 8% per annum. On December 31, 2018, proceeds from the Marathon Credit Agreement were utilized to repay all outstanding amounts under the Arosa Loan.

In conjunction with the Arosa Loan, the Company issued Arosa a warrant to purchase 5,000,358 shares of common stock of the Company at an exercise price of $2.00 per share exercisable in cash only for a period of five years. While the Arosa Loan remained outstanding, the Company was required to issue additional warrants to purchase common stock equal to 10% of any additional issuance of common stock.

The Arosa Loan and related warrants were considered freestanding instruments and were accounted for separately. The warrants did not qualify for equity accounting and liability treatment was applied. The fair value of the warrants on the date of the Arosa Loan was estimated to be $3,540,542, using the Black-Scholes valuation method and was recorded as a liability with the offset being recorded as a debt discount. Through and including December 31, 2018, the warrants held by Arosa were required to be marked-to-market as the warrants were classified as liabilities. On January 1, 2019, the warrants no longer included anti-dilution protection and no longer met the criteria for liability classification at which time they were reclassified to equity. As a result of the 2019 reclassification event, the $857,072 Arosa warrant liability was reclassified to Additional Paid-In Capital.

On August 14, 2018 the Company issued Arosa a warrant to acquire 1,143,200 shares of common stock at an exercise price of $1.21 following the closing of the Company's August 2018 public offering. On October 1, 2018, the Company issued Arosa a warrant to acquire 108,768 shares of common stock at an exercise price of $1.60 warrants, due to our third quarter At The Market (“ATM”) offerings. On the payoff of the Arosa Loan, the Company issued Arosa a Warrant to purchase 894,821 shares of common stock exercisable at $1.25 per share.

A loss on extinguishment of approximately $2.2 million was recognized on the payoff of the Arosa Loan which is recorded in Interest Expense in the accompanying Consolidated Statement of Operations for the year ended December 31, 2018.