Note 6 - Warrants

6 Months Ended

Jun. 30, 2025

Notes to Financial Statements

Warrants [Text Block]

Note 6. Warrants

We have certain warrants outstanding to purchase our common stock, at various prices, for the six months ended June 30, 2025 and 2024 is as follows:

	Warrants outstanding			Weighted average price per share		Weighted average remaining life		Aggregate intrinsic value(1)
Balance, December 31, 2023		51,590,300		$	0.27
Granted		4,127,516		$	0.27
Exercised		(967,748	)	$	0.23
Expired		(5,562,754	)	$	0.21
Vested Balance, June 30, 2024		49,187,314		$	0.27
Balance, December 31, 2024		31,615,616		$	0.29
Expired		(1,888,170	)	$	0.21
Vested Balance, June 30, 2025		29,727,446		$	0.29		2.0	$	40,000

(1) – Aggregate intrinsic value based on closing common stock price of $0.21 at June 30, 2025.

Warrants issued in Unit Offerings

We did not issue any warrants in conjunction with unit offerings in the six months ended June 30, 2025.

During the three months ended  June 30, 2024, we issued six-month stock purchase warrants to purchase an aggregate 454,547 shares of our common stock at $0.33 per share, and five-year stock purchase warrants to purchase an aggregate 454,547 shares of our common stock at $0.33 per share, in conjunction with the sale of stock to investors in our Unit Offerings (see Note 3). The relative fair value of the warrant component of the units sold to investors totaled $93,000.  During the three months ended  March 31, 2024, we issued six-month stock purchase warrants to purchase an aggregate 1,394,737 shares of our common stock at $0.23 per share, and five-year stock purchase warrants to purchase an aggregate 1,394,737 shares of our common stock at $0.29 per share, in conjunction with the sale of stock to investors in our Unit Offerings (see Note 3). In addition to warrants issued to investors, we issued five-year stock purchase warrants to purchase an aggregate 428,948 shares of our common stock at $0.19 per share as commissions. The relative fair value of the warrant component of the units sold to investors totaled $201,000.  The Black-Scholes model was used to calculate relative fair value, further discounted by the beneficial conversion feature and the value of the common stock component. 

During the six months ended  June 30, 2024, investors exercised warrants to purchase 967,748 shares of our common stock, and we received $216,000 in proceeds.

Warrant Fair Value

We use the Black-Scholes option pricing model to determine the relative fair value of warrants issued in conjunction with debt instruments, common stock, and for services. With respect to debt instruments, relative fair value is amortized over the life of the warrant. The principal assumptions we used in applying the Black-Scholes model were as follows:

	2025			2024
Risk free interest rate		—	%		3.69 - 5.38	%
Expected volatility		—	%		64 - 95	%
Expected dividend yield		—			—
Forfeiture rate		—			—
Expected life in years		—			.5 - 5

The risk-free interest rate is based on U.S. Treasury yields in effect at the time of grant. Expected volatilities are based on historical volatility of our common stock. The expected life in years is based on the contract term of the warrant.