Note 6 - Warrants

9 Months Ended

Sep. 30, 2022

Notes to Financial Statements

Warrants [Text Block]

Note 6.   Warrants

We issued warrants to purchase our common stock, at various prices for the nine months ended September 30, 2022 and 2021, is as follows:

							Weighted
							average		Aggregate
	Warrants			Exercise			price per		Intrinsic
	outstanding			price per share			share		value(1)
Balance, December 31, 2021		36,765,502		$0.16	–	1.00	$	0.27
Issued		27,137,048		0.19	–	0.33		0.23
Expired		(10,273,722	)	0.19	–	0.48		0.25
Balance, September 30, 2022		53,628,828		$0.14	–	1.00	$	0.26	$	2,094,000
Balance, December 31, 2020		32,980,989		$0.16	–	1.00	$	0.29
Issued		7,865,872		0.14	-	0.27		0.20
Exercised		(416,667	)		0.14			0.14
Expired		(2,743,406	)	0.12	-	0.70		0.59
Balance, September 30, 2021		37,686,788		$0.12	–	1.00	$	0.27

(1) Aggregate intrinsic value based on closing common stock price of $0.27 at September 30, 2022

Warrants issued in Unit Offerings

During the nine months ended September 30, 2022, pursuant to our Unit Offerings (see Note 3), we issued nine-month stock purchase warrants to purchase an aggregate 13,568,524 shares of our common stock at $0.19 - $0.23 per share, and five-year stock purchase warrants to purchase an aggregate 13,568,524 shares of our common stock at $0.24 - $0.33 per share.

During the nine months ended  September 30, 2021, pursuant to our Unit Offerings (see Note 3), we issued six-month stock purchase warrants to purchase an aggregate 3,932,936 shares of our common stock at exercise prices between $0.14 – 0.22 per share, and five-year stock purchase warrants to purchase an aggregate 3,923,936 shares of our common stock at exercise prices between $0.18 – 0.27 per share.

On  August 6, 2021 a holder of a six-month stock purchase warrant exercised the warrant and we received $60,000 and issued 416,667 shares of our common stock.

Fair Value – Interest Expense

To determine interest expense related to our outstanding warrants issued in conjunction with debt offerings, the fair value of each award grant is estimated on the date of grant using the Black-Scholes option pricing model and the relative fair values are amortized over the life of the warrant. For the determination of expense of warrants issued for services, extinguishment of debt and settlement, management also uses the option-pricing model. During the nine months ended September 30, 2022 and 2021, no warrants were issued in conjunction with debt offerings.

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.