9. Additional Paid-in Capital


		Warrants		Stock options and RSUs		Compensation options		Other paid-in capital		Total additional paid-in capital

As of December 31, 2012	$	12,936	$	7,655	$	294	$	11,270	$	32,155
Stock options amortization		-		108		-		-		108
Restricted stock units expensed		-		768		-		-		768
Restricted stock units exercised		-		(153)		-		-		(153)
As of March 31, 2013	$	12,936	$	8,378	$	294	$	11,270	$	32,878

Warrants

Warrant activity is summarized in the following table:


	Warrants outstanding		Valuation		Weighted average exercise price per share	Weighted average remaining life (yrs.)		Intrinsic value

As of December 31, 2012	19,977,743	$	12,936	$	4.25	2.6	$	-
As of March 31, 2013	19,977,743	$	12,936	$	4.25	2.3	$	-

The 19,977,743 outstanding warrants expire in the following time frames: 2,666,666 expire in July 2014, 2,091,275 expire in December 2014, and 15,219,802 expire in October 2015.

Compensation Options


	Compensation options outstanding		Valuation		Weighted average exercise price per share	Expiry date	Weighted average remaining life (yrs.)

As of December 31, 2012	225,000	$	294	$	3.30	April 2013	0.3
As of March 31, 2013	225,000	$	294	$	3.30	April 2013	0.1

These options expired unexercised on April 20, 2013.

Stock-Based Compensation

Under our Stock Option Plan (the “Plan”) and our Long-Term Equity Incentive Plan (the “LTIP”), we may grant options and/or restricted stock units (“RSUs”) or restricted stock awards (“RSAs”) to our directors, officers, employees and consultants. The combined maximum number of our common shares that may be reserved for issuance under the Plan and the LTIP is a variable number equal to 10% of the issued and outstanding common shares on a non-diluted basis. Options under the Plan are granted from time to time at the discretion of the Board of Directors (“Board”), with vesting periods and other terms as determined by the Board. The LTIP is administered by the Board, which can delegate the administration to the Compensation Committee of the Board or to such other officers and employees of Vista as designated by the Board. Stock-based compensation expense for the three months ended March 31, 2013 and 2012 is as follows:


		Three months ended March 31,
		2013		2012

Stock options	$	108	$	237
Restricted stock units		768		775
	$	876	$	1,012

As of March 31, 2013, stock options and RSUs had unrecognized compensation expense of $206 and $2,875, respectively, which is expected to be recognized over a weighted average period of 0.51 and 1.71 years, respectively.

Stock Options

A summary of option activity under the Plan as of March 31, 2013 and changes during the period then ended is set forth in the following table:


	Number of options		Weighted average exercise price per option	Weighted average remaining contractual term		Aggregate intrinsic value
Outstanding - December 31, 2012	3,102,500	$	2.80	2.68	$	637
Outstanding - March 31, 2013	3,102,500	$	2.80	2.43	$	248

Exercisable - March 31, 2013	2,802,500	$	2.79	2.25	$	248

A summary of the status of our unvested stock options as of March 31, 2013 and changes during the period then ended is set forth in the following table:


	Number of options		Weighted average grant-date fair value per option	Weighted average remaining amortization period (Years)
Unvested - December 31, 2012	300,000	$	1.47
Unvested - March 31, 2013	300,000	$	1.47	0.51

Restricted Stock Units

The following table summarizes the RSU activity under the LTIP as of March 31, 2013 and changes during the period then ended is set forth in the following table:


	Number of units		Weighted average fair value
Unvested - December 31, 2012	1,994,507	$	3.52
Cancelled/forfeited	(9,288)		3.23
Vested	(50,000)		3.07
Granted	51,424		1.68
Unvested - March 31 , 2013	1,986,643	$	3.47

On March 5, 2013, the Board granted a total of 51,424 RSUs to an employee. 40% of the RSUs granted vest three years from the grant date and the remaining 60% vest based on the performance of the Company’s share price relative to the average of the AMEX Gold Basket of Unhedged Gold Stocks Index and Philadelphia Gold and Silver Sector Index (the “Benchmark”) expressed as a percent change over the period. The lower threshold is defined by the Company’s share price underperforming the Benchmark by 20% and the upper threshold is defined by the Company’s share price exceeding the Benchmark by 20%. Vesting will be calculated linearly with the lower threshold being zero, performance equal to the Benchmark being 50% and the upper threshold being 100%. If the performance vesting conditions are not met within 24 months of the date of grant, the RSUs are cancelled and of no further force and effect.