Stockholders' Equity (Tables)
 6 Months Ended
Jun. 30, 2012
Stockholders' Equity  
Schedule of outstanding warrants to purchase common stock

 

 

 

 

Number of
Shares

 

Exercise Price

 

Expiration

 

Common Stock

 

140,520

 

$

7.45

 

2016 through 2020

 

Common Stock

 

59,748

 

$

7.95

 

2016

 

 

 

 

 

 

 

 

 

 

 

200,268

 

 

 

 

 

 
Schedule of stock option activity

 

 

 

 

Number of
Shares

 

Weighted
Average
Exercise
Price

 

Weighted
Average
Remaining
Contractual
Term in Years

 

Aggregate
Intrinsic
Value

 

Outstanding at January 1, 2012

 

1,784,285

 

$

4.31

 

 

 

 

 

Granted

 

714,630

 

3.09

 

 

 

 

 

Exercised

 

(6,237

)

1.92

 

 

 

 

 

Cancelled/forfeited

 

(184,388

)

8.80

 

 

 

 

 

Outstanding at June 30, 2012

 

2,308,290

 

3.58

 

7.95

 

$

3,031

 

Vested and expected to vest at June 30, 2012

 

2,197,952

 

3.61

 

7.86

 

$

2,924

 

Exercisable at June 30, 2012

 

1,199,334

 

3.03

 

6.74

 

$

2,100

 

 
Schedule of assumptions used in determining the fair value of stock options

 

 

Weighted- average fair value of stock options granted

 

$

2.14

 

 

 

 

 

Assumptions Used:

 

 

 

Risk-free interest rate

 

0.73 - 1.18

%

Expected life in Years

 

5.0 - 6.1 years

 

Expected volatility

 

80.5- 88.1

%

Dividend Yield

 

0

%

 
Schedule of restricted stock activity

 

 

 

 

Number of
Shares

 

Weighted
Average
Grant Date
Fair Value

 

Nonvested shares at December 31, 2011

 

16,000

 

$

7.73

 

 

 

 

 

 

 

Granted

 

—

 

—

 

Vested

 

(4,000

)

—

 

Forfeited/repurchased

 

—

 

—

 

 

 

 

 

 

 

Nonvested shares at June 30, 2012

 

12,000

 

$

7.73