15. Warrant Liability

On February 21, 2024, September 2, 2021, March 11, 2021, February 3, 2021, December 24, 2020, March 18, 2020, September 10, 2019, and November 6, 2019, the Company issued 27,725, 22,019, 34,285, 7,429, 7,286, 44,286, 35,714 and 114,286 warrants, respectively, as equity issuance consideration, in connection with equity offering of the Company’s common stock. The warrants entitle the holder to purchase one share of our common stock at an exercise price equal to $0.49 to $5.25 per share at any time on or after their issuance date and on or prior to the close of business 3 years after the issuance date (the “Termination Date”). The Company determined that these warrants are free standing financial instruments that are legally detachable and separately exercisable from the common stock included in the public share offering. Management also determined that the warrants required classification as a liability pursuant to ASC 815, Derivatives and Hedging. In accordance with the accounting guidance, the outstanding warrants are recognized as a warrant liability on the balance sheet and are measured at their inception date fair value and subsequently re-measured at each reporting period with changes being recorded as a component of other income (expense) in the condensed consolidated statements of operations.

The warrants outstanding and fair values at each of the respective valuation dates are summarized below:

 Schedule of Warrant Liability

The following assumptions were used to calculate the warrant liability for three months ended March 31, 2024 and 2023:

 Schedule of Assumptions Used in Warrant Liability

The warrant liabilities are considered Level 3 liabilities on the fair value hierarchy as the determination of fair value includes various assumptions about of future activities and the Company’s stock prices and historical volatility of Guideline Public Companies as inputs.