9. Common Stock Warrants As of June 30, 2025 and December 31, 2024, the following common stock warrants were outstanding: | | | | | | | | | | | | | | | | | | Exercise Price | | June 30, | | December 31, | Issuance Date | | Expiration Date | | Balance Sheet Classification | | per Share | | 2025 | | 2024 | May 2018 | | May 2028 | | Stockholders’ equity | | $ | 23.69 | | 6,332 | | 6,332 | March 2019 | | March 2029 | | Stockholders’ equity | | $ | 14.71 | | 4,845 | | 4,845 | December 2023 | | December 2033 | | Stockholders’ equity | | $ | 35.00 | | 40,000 | | 40,000 | December 2023 | | December 2033 | | Stockholders’ equity | | $ | 42.50 | | 40,000 | | 40,000 | December 2023 | | December 2033 | | Stockholders’ equity | | $ | 50.00 | | 40,000 | | 40,000 | | | | | | | | | | 131,177 | | 131,177 |
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