3. FAIR VALUE

In accordance with the Fair Value Measurements and Disclosures Topic of ASC 820, the Company groups its financial assets and financial liabilities generally measured at fair value in three levels, based on the markets in which the assets and liabilities are traded, and the reliability of the assumptions used to determine fair value:

To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying value of cash and cash equivalents approximates fair value as maturities are less than three months. The carrying amounts reported for other current financial assets and liabilities approximate fair value because of their short-term nature. As of March 31, 2024, the Company does not have any Level 1 or Level 2 liabilities.

As part of the September 2023 financing (see Note 2) the Company issued Tranche A and Tranche B warrants to purchase shares of preferred stock which, on an as-converted basis, represented an aggregate of 21,025,641 shares of common stock. The fair value of the Tranche A and B warrants was determined using a probability-weighted expected return method (PWERM) with a scenario-based Monte Carlo simulation and Black-Scholes model. The PWERM is a scenario-based methodology that estimates the fair value of the Company’s different classes of equity based upon an analysis of future values for the Company, assuming various outcomes. Under both models, assumptions and estimates are used to value the preferred stock warrants. The Company assesses these assumptions and estimates on a quarterly basis as additional information that impacts the assumptions is obtained. The quantitative elements associated with the inputs impacting the fair value measurement of the Tranche A and B warrants include the value per share of the underlying common stock, the timing, form and overall value of the expected exits for the stockholders, the risk-free interest rate, the expected dividend yield and the expected volatility of the Company’s shares. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve for time periods approximately equal to the remaining contractual term of the warrants. The Company estimated a 0% dividend yield based on the expected dividend yield and the fact that the Company has never paid or declared cash dividends. Expected volatility was determined based upon the historical volatility of the Company’s common stock.

The Tranche A and B warrants are classified within the Level 3 hierarchy because of the nature of these inputs and the valuation technique utilized. The September 2023 Warrants had a fair value of $8,800,000 and $4,200,000 as of March 31, 2024 and December 31, 2023, respectively, which is included in the warrant liability caption on the accompanying balance sheets.

The following table summarizes the modified option-pricing assumptions used on December 31, 2023, and March 31, 2024:

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At the time the Tranche A warrants were exercised, their fair value, calculated as the difference between the common stock conversion rate in the Series E-3 preferred stock and the trading price of the stock when the warrants were exercised, was determined to be $4,800,000. Due to the settlement of the Tranche A warrants relieving the Company of any further related obligation, the liability was reclassified to equity in accordance with ASC 815. The Tranche B warrants continue to be classified as a liability due to a cash settlement feature in the agreement.

In October 2022 the Company issued a total of 5,151,098 common warrants that are immediately exercisable with a five-year life and a strike price of $1.96 for shares of common stock (the 2022 Common Warrants), and 1,875,941 pre-funded warrants (the 2022 Pre-Funded Warrants) to acquire shares of common stock (see Note 6). The 2022 Pre-Funded Warrants are exercisable by the holder upon payment of the par value of the common stock and are classified as Level 2 liabilities as their value is equal to the Company’s common stock value less the par value of $0.00001 per share. As noted above, the Pre-Funded Warrants were fully exercised by March 31, 2024.

The fair value of the 2022 Common Warrants was determined by utilizing a Black-Scholes option-pricing model. The quantitative elements associated with the inputs impacting the fair value measurement of the 2022 Common Warrants include the value per share of the underlying common stock, the risk-free interest rate, the expected dividend yield and the expected volatility of the Company’s shares. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve for time periods approximately equal to the remaining contractual term of the warrants. The Company estimated a 0% dividend yield based on the expected dividend yield and the fact that the Company has never paid or declared cash dividends. Expected volatility was determined based upon the historical volatility of the Company’s common stock. These warrants are classified within the Level 3 hierarchy because of the nature of these inputs and the valuation technique utilized. The following table summarizes the assumptions used at each financial reporting date:

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The following table summarizes the changes in the fair market value of the warrants which are classified within the Level 3 fair value hierarchy, inclusive of the September 2023 Warrants and the October 2022 Warrants:

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