11. STOCK-BASED COMPENSATION

Stock-based compensation awards consist of stock options, restricted stock units and bonus shares issued under the Company’s equity incentive plans which include: the 2013 Omnibus Incentive Plan (the “2013 Plan”), the Amended and Restated 2004 Directors’ Stock Option and Restricted Stock Plan (the “2004 Directors’ Plan”) and the 2004 Stock Incentive Plan (the “2004 Plan”). Upon approval of the 2013 Plan by the Company’s stockholders on June 4, 2013, the Company’s authority to grant new awards under all plans other than the 2013 Plan was terminated. On July 18, 2017 and April 18, 2019, the Company’s stockholders approved amendments to the 2013 Plan to increase the authorized number of shares of common stock available and reserved for issuance under the 2013 Plan by 20,000 shares and 66,000 shares, respectively. Under the 2013 Plan, the Company may grant awards of stock options, stock appreciation rights, restricted stock awards (“RSAs”), restricted stock units (“RSUs”), unrestricted stock, dividend equivalent rights, performance shares and other performance-based awards, other equity-based awards and cash bonus awards to eligible persons. The maximum number of the Company’s common stock that may be reserved for issuance under the 2013 Plan is currently 66,278 shares of common stock, plus unissued shares under the prior plans. Equity awards under the 2013 Plan are granted from time to time at the discretion of the Compensation Committee of the Board (the “Committee”), with vesting periods and other terms as determined by the Committee with a maximum term of 10 years. The 2013 Plan is administered by the Committee, which can delegate the administration to the Board, other Committees or to such other officers and employees of the Company as designated by the Committee and permitted by the 2013 Plan.

As of April 18, 2019, 66,278 shares were available for future issuances under the 2013 Plan. For the three months ending March 31, 2019 and 2018, the Company recorded stock-based compensation expense of $7,719 and $80,673, respectively. Stock compensation expense is recorded in general and administrative expenses.

In addition to the plans above, upon closing of the Company’s acquisition of Anatolia Energy Limited in November 2015, the Company issued 7,495 replacement options and performance shares to the option holders and performance shareholders of Anatolia Energy Limited. The number of replacement options and performance shares was based upon the Black-Scholes value with the exercise prices of the replacement options and performance shares determined using the exchange rate of 0.0001096. The options and performance shares were issued with the same terms and conditions as were applicable prior to the acquisition of Anatolia Energy Limited. As of March 31, 2019, there were 449 replacement options outstanding and no performance shares outstanding.

In addition to the plans above, upon closing of the Company’s acquisition of Alabama Graphite in April 2018, the Company issued 50,168 replacement options and warrants to the option and warrant holders of Alabama Graphite. The number of replacement options and warrants shares was determined using the arrangement exchange rate of 0.0016. The exercise prices for the option and warrant shares were first converted for the exchange rate of 0.0016 and then converted to USD using the exchange rate on December 13, 2017 of 0.77809 (CAD to USD). The options and warrant shares were issued with the same terms and conditions as were applicable prior to the acquisition of Alabama Graphite. As of March 31, 2019, there were 5,568 replacement options and 11,440 replacement warrants outstanding.

Stock Options

The following table summarizes stock options outstanding and changes for the three-month periods ending March 31, 2019 and 2018:


	March 31, 2019			March 31, 2018
		Weighted			Weighted
	Number of	Average		Number of	Average
	Stock	Exercise		Stock	Exercise
	Options	Price		Options	Price
Stock options outstanding at beginning of period	19,170	$	79.78	5,723	$	276.50
Granted	—		—	—		—
Expired	(280)		179.68	(112)		624.00
Stock options outstanding at end of period	18,890	$	78.21	5,611	$	269.50
Stock options exercisable at end of period	18,890	$	78.21	1,828	$	682.50

The following table summarizes stock options outstanding and exercisable by stock option plan at March 31, 2019:


	Outstanding Stock Options			Exercisable Stock Options
	Number of	Weighted		Number of	Weighted
	Outstanding	Average		Exercisable	Average
Stock Option Plan	Stock Options	Exercise Price		Stock Options	Exercise Price
2004 Plan	96	$	1,752.25	96	$	1,752.25
2004 Directors’ Plan	11		9,332.73	11		9,332.73
2013 Plan	12,766		35.41	12,766		35.41
Replacement Stock Options-Alabama Graphite	5,568		80.96	5,568		80.96
Replacement Stock Options-Anatolia Energy	449		676.22	449		676.22
	18,890	$	78.21	18,890	$	78.21

Restricted Stock Units

Time-based and performance-based RSUs are valued using the closing share price of the Company’s common stock on the date of grant. The final number of shares issued under performance-based RSUs is generally based on the Company’s prior year performance as determined by the Compensation Committee of the Board of Directors at each vesting date, and the valuation of such awards assumes full satisfaction of all performance criteria.

The following table summarizes RSU activity for the three-month periods ended March 31, 2019 and 2018:


	March 31,			March 31,
	2019			2018
		Weighted-			Weighted-
		Average			Average
	Number of	Grant Date		Number of	Grant Date
	RSUs	Fair Value		RSUs	Fair Value
Unvested RSUs at beginning of period	2,260	$	70.00	3,578	$	70.00
Granted	—		—	—		—
Forfeited	(565)		70.00	(189)		70.00
Vested	—		—	—		—
Unvested RSUs at end of period	1,695	$	70.00	3,389	$	70.00