| Schedule of Warrant Activity |
In connection with the issuance of debt, common stock and preferred stock, the Company has issued warrants to purchase shares of the Company's common stock. The following table summarizes warrant activity: | | | | | | | | | | | | | | | | | Number of Warrants | | Weighted Average Exercise Price per Warrant | | Balance, December 31, 2018 | | 17,818,844 | | | $ | 1.84 | | | Granted, Series B Preferred Stock | | 9,262,500 | | | 1.62 | | | Granted, Marathon Credit Agreement | | 3,379,466 | | | 2.26 | | | Granted, Other | | 66,966 | | | 5.28 | | | Exercised | | — | | | — | | | Balance, December 31, 2019 | | 30,527,776 | | | 1.82 | | | Granted, Marathon Credit Agreement | | 1,176,203 | | | 28.26 | | | Exercised | | (30,502,763) | | | 1.78 | | | Expired | | (45,540) | | | 1.60 | | | Balance, December 31, 2020 | | 1,155,676 | | | $ | 28.74 | |
|