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Warrants | 12 Months Ended
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Dec. 31, 2019
Warrants and Rights Note Disclosure [Abstract] |
Warrants | 13. WARRANTS Warrants to purchase 1,167,064 and 13,927 shares of common stock expired during 2019 and 2018, respectively. During 2018, the Company and certain investors holding warrants to collectively purchase 1.6 million shares of the Company’s common stock, entered into warrant exchange agreements whereby the Company issued 820,714 shares of its common stock in exchange for the cancellation of the warrants. Following is a summary of all warrant activity for the two years ended December 31, 2019:
Warrants |  | Number of Warrants Issued |  |  | Weighted Average Exercise Price |
Warrants outstanding at January 1, 2018 |  |  | 3,058,402 |  |  | $ | 5.29 |
Warrants issued in connection with 2018 equity transactions |  |  | 190,114 |  |  | $ | 2.63 |
Warrants cancelled in exchange for common stock |  |  | (1,641,427 | ) |  | $ | 3.04 |
Warrants expired during 2018 |  |  | (13,927 | ) |  | $ | 226.24 |
Warrants outstanding at December 31, 2018 |  |  | 1,593,162 |  |  | $ | 5.36 |
Warrants issued during 2019 (see Note 12) |  |  | 200,000 |  |  | $ | 0.01 |
Warrants expired during 2019 |  |  | (1,167,064 | ) |  | $ | 6.32 |
Warrants outstanding and exercisable at December 31, 2019 |  |  | 626,098 |  |  | $ | 1.87 |
Aggregate intrinsic value of outstanding warrants at December 31, 2019 |  | $ | 340,000 |  |  |  |  |
Weighted average remaining contractual terms (years) |  |  | 1.87 |  |  |  |  |
Schedule of weighted average remaining contractual terms at December 31, 2019 |  | Number of Warrants Issued |  |  | Weighted Average Exercise Price |  |  | Weighted Average Contractual Terms Remaining
Warrants provided to EGWU, Inc (Note 12) |  |  | 200,000 |  |  | $ | 0.01 |  |  | No expiration
All other warrants outstanding |  |  | 426,098 |  |  | $ | 2.74 |  |  | 5.3 years

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