The following table summarizes the changes in warrants outstanding and the related exercise prices for the warrants issued to non-employees of the Company.
| Warrants Outstanding | Warrants Exercisable | |||||||||||||||||||||
| Exercise Prices | Number Outstanding |
Weighted Average Remaining Contractual Life (Years) |
Weighted Average Exercise Price |
Number Exercisable |
Weighted Average Exercise Price |
|||||||||||||||||
| $ | 0.13 | 7,230,778 | 2.11 | $ | 0.13 | 7,230,778 | $ | 0.13 | ||||||||||||||
| 0.33 | 1,628,800 | 0.88 | 0.33 | 1,628,800 | 0.33 | |||||||||||||||||
| 3.00 | 500,336 | 1.61 | 3.00 | 500,336 | 3.00 | |||||||||||||||||
| 9,359,914 | 1.87 | $ | 0.32 | 9,359,914 | $ | 0.32 | ||||||||||||||||
Transactions involving warrants are summarized as follows:
| Number
of Shares |
Weighted
Average Exercise Price |
|||||||
| Outstanding at January 1, 2012 | 14,921,920 | $ | 0.50 | |||||
| Issued | – | – | ||||||
| Exercised | (3,115,390 | ) | 0.13 | |||||
| Canceled or expired | (976,114 | ) | 2.20 | |||||
| Outstanding at December 31, 2012 | 10,830,416 | $ | 0.45 | |||||
| Issued | – | – | ||||||
| Exercised | (86,472 | ) | 0.13 | |||||
| Canceled or expired | (1,384,030 | ) | 1.36 | |||||
| Outstanding at December 31, 2013 | 9,359,914 | $ | 0.32 | |||||