In 2018, our stockholders approved the adoption of the SenesTech, Inc. 2018 Equity Incentive Plan (the “2018 Plan”). The 2018 Plan has since been amended and restated on certain occasions, most recently on June 23, 2023, when our stockholders approved an increase to the total number of authorized shares to 207,071 shares of common stock.

Stock options are generally issued with a per share exercise price equal to the fair market value of our common stock at the date of grant. Options granted generally vest ratably over a 1- to 3-year period coinciding with their respective service periods, with terms generally of ten years. Certain stock option awards provide for accelerated vesting upon a change in control.

On October 15, 2025, the Company’s Board of Directors approved the grant of stock options to purchase up to 420,000 shares of common stock to the Company’s Board members pursuant to a proposed amendment to the 2018 Plan (the “Contingent Stock Options”). The Board intends to propose to amend the 2018 Plan to increase the number of shares available for issuance thereunder to ensure that the Company has sufficient shares to attract, retain, and motivate key employees and directors.

The Contingent Stock Options have an exercise price of $4.05 per share, vest in four equal installments of 25% on each of January 15, 2026, April 15, 2026, July 15, 2026, and October 15, 2026, and have a contractual term expiring October 15, 2035. The grants are contingent upon stockholder approval of the amended 2018 Plan by October 15, 2026. If such approval is not obtained by that date, the Contingent Stock Options will be rescinded, terminated, and deemed void ab initio, as if the grant had never occurred.

As of December 31, 2025, the Contingent Stock Options remained outstanding in form. Under ASC 718, Compensation—Stock Compensation, a contingency is substantive if (i) achievement is not assured at the grant date; (ii) there is meaningful uncertainty about whether it will be met; (iii) failure is plausible, based on facts and circumstances; and (iv) the conditions requires performance outcomes. Accordingly, no accounting recognition was recorded because the arrangement did not meet the definition of a grant date under ASC 718 due to the substantive contingency of stockholder approval.

We measure the fair value of stock options with service-based vesting criteria to employees, directors and consultants on the date of grant using the Black-Scholes option pricing model. The Black-Scholes valuation model requires us to make certain estimates and assumptions, including assumptions related to the expected price volatility of our stock, the expected period during which the options will be outstanding, the rate of return on risk-free investments, and the expected dividend yield for our stock.

Fair value of options granted is determined using the Black-Scholes option-pricing model with the following weighted average assumptions:


	2025		2024
Risk-free interest rate	4.7	%	3.8	%
Expected dividend yield	—	%	—	%
Expected volatility	162	%	128.0	%
Expected term (in years)	10.0		10.0

The weighted average fair value of options granted during the years ended December 31, 2025 and 2024 was $3.08 and $2.73 per share, respectively. The risk-free interest rate is estimated using treasury bill interest rates. The expected dividend yield is zero as we have not paid any dividends to date and do not expect to pay dividends in the future. Expected volatility is estimated based on the historical volatility of our common stock over the expected term as this represents our best estimate of future volatility. We use the “simplified method” to estimate expected term. Under the simplified method, an option’s expected term is calculated as the time until expiration.


	Number of Options		Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (1)
Outstanding as of December 31, 2023	3,645		$	1,197.00	4.0	$	—
Granted	144,204		2.38		9.6	—
Exercised	—		—		—	—
Forfeited	(224)		—		—	—
Expired	(9)		—		—	—
Outstanding as of December 31, 2024	147,616		27.13		9.5	—
Granted	28,057		3.09		9.3	—
Exercised	—		—		—	—
Forfeited	(11)		—		—	—
Expired	(84)		—		—	—
Outstanding as of December 31, 2025	175,578		20.75		8.8	—
Exercisable as of December 31, 2025	115,262	(2)	30.10		8.7	—



(1)			Calculated based on the difference between the estimated fair value of our stock and the exercise price of the underlying option. The estimated stock values used in the calculation were $3.09 and $2.83 per share for the years ended December 31, 2025 and 2024, respectively.
(2)			Includes options related to 603 shares that are inducement awards and not granted under the 2018 Plan.

As of December 31, 2025, the unrecognized stock-based compensation cost was $162,000, which is expected to be recognized over a weighted average period of 1.7 years.


	Years Ended December 31,
	2025		2024
Research and development	$	11	$	13
General and administrative	253		313
Total stock-based compensation expense	$	264	$	326