FAIR VALUE

FASB guidance on fair value measurements, which defines fair value, establishes a framework for measuring fair value, and expands disclosures about fair value measurements for our financial assets and liabilities, as well as for other assets and liabilities that are carried at fair value on a recurring basis in our consolidated financial statements.

FASB guidance establishes a three-level fair value hierarchy based upon the assumptions (inputs) used to price assets or liabilities. The three levels of inputs used to measure fair value are as follows:

Level 1—Unadjusted quoted prices in active markets for identical assets or liabilities;

Level 2—Observable inputs other than those included in Level 1, such as quoted prices for similar assets and liabilities in active markets or quoted prices for identical assets or liabilities in inactive markets; and

Level 3—Unobservable inputs reflecting our own assumptions and best estimate of what inputs market participants would use in pricing the asset or liability.

Debt

Our debt is considered a Level 3 liability for which book value approximates fair value due to the variable interest rate it bears.

Common Stock Warrant Liabilities.

Certain of our issued and outstanding warrants to purchase common stock do not qualify to be treated as equity and, accordingly, are recorded as a liability.

2012 Warrant Liability

The 2012 Warrant Liability represents the fair value of the 3.4 million warrants issued in February 2012 (as adjusted pursuant to the terms of the 2012 warrants). We are required to record these instruments at fair value at each reporting date and changes are recorded as a non-cash adjustment to earnings. The gains or losses included in earnings are reported in other income (expense) in our Statement of Operations. Management does not believe that this liability will be settled by a use of cash.

The 2012 Warrant Liability is considered a Level 3 financial instrument and is valued using a Monte Carlo simulation. This method is well suited to value options with non-standard features, such as anti-dilution protection. A Monte Carlo simulation model uses repeated random sampling to simulate significant uncertainty in inputs. Assumptions and inputs used in the valuation of the common stock warrants are broken down into four sections: Static Business Inputs; Static Technical Inputs; Simulated Business Inputs; and Simulated Technical Inputs.

Static Business Inputs include: Our equity value, which was estimated using our stock price of $0.28 as of December 31, 2016; the amount of the down-round financing, the timing of the down-round financing, the expected exercise period of 0.10 years from the valuation date and the fact that no other potential fundamental transactions are expected during the term of the common stock warrants.

Static Technical Inputs include: volatility of 67% based on implied and historical rates over the expected term and the risk-free interest rate of 0.44% based on the 1-month U.S. Treasury yield.

Simulated Business Inputs include: the probability of down-round financing, which was estimated to be 25% for simulated equity values below the down-round financing cut-off point.

Simulated Technical Inputs include: our equity value in periods 1-10 follows a geometric Brownian motion and is simulated over 10 independent six-month periods; a down-round financing event was randomly simulated in an iteration based on the 25% discrete probability of a down-round financing for those iterations where our simulated equity value at the expected timing of down-round financing was below the down-round financing cut-off point.

During the year ended December 31, 2016, the changes in the fair value of the liability measured using significant unobservable inputs (Level 3) was comprised of the following:



	Dollars in Thousands
	For the Year Ended
	December 31, 2016
Balance at January 1, 2016	$	350
Total gains or losses:
Recognized in earnings	(350		)
Balance at December 31, 2016	$	—

2016 Warrant Liability

The 2016 Warrant Liability represents the fair value of the 1.8 million warrants issued in January 2016, of which, 0.8 million warrants remain outstanding as of December 31, 2016. We are required to record these instruments at fair value at each reporting date and changes are recorded as a non-cash adjustment to earnings. The gains or losses included in earnings are reported in other income (expense) in our Statement of Operations.

The 2016 Warrant Liability is considered a Level 3 financial instrument and is valued using a binomial lattice simulation model. This method is well suited to valuing options with non-standard features. Assumptions and inputs used in the valuation of the common stock warrants include; our equity value, which was estimated using our stock price of $0.28 as of December 31, 2016; volatility of 91%; and a risk-free interest rate of 1.70%.

During the year ended December 31, 2016, the changes in the fair value of the liability measured using significant unobservable inputs (Level 3) were comprised of the following:



	Dollars in Thousands
	For the Year Ended
	December 31, 2016
Balance at January 1, 2016	$	—
Additions	1,827
Deductions from warrant conversions	(807		)
Total gains or losses:
Recognized in earnings	(438		)
Balance at December 31, 2016	$	582

The change in unrealized gains or losses of Level 3 liabilities is included in earnings and is reported in other income (expense) in our Statement of Operations.