Stock Options (Tables)

12 Months Ended

Aug. 31, 2021

Share-based Payment Arrangement [Abstract]

Assumptions

	Years Ended August 31,
	2021	2020
Expected dividend yield	–	–
Expected stock price volatility	89.44%	82.94 – 86.23%
Risk-free interest rate	0.19%	1.40 – 1.69%
Expected term (in years)(simplified method)	4.00	1.87 – 5.75
Exercise price	$3.42	$2.32 - $8.00
Weighted-average grant date fair-value	$2.16	$1.15 - $1.84

Stock option activity

	Number of Shares Subject to Option Grants			Weighted Average Exercise Price ($)		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value ($)
Outstanding at August 31, 2019		2,777,334			4.31
Grants		5,158,000			4.06
Forfeitures and cancellations		(130,600	)		3.54
Outstanding at August 31, 2020		7,804,734			4.16
Grants		50,000			3.42
Exercises		(56,667	)		4.95
Forfeitures and cancellations		(1,057,667	)		5.30
Outstanding at August 31, 2021 (years)		6,740,400			3.97		4.29		13,275,179
Exercisable at August 31, 2021 (years)		5,980,900			4.02		4.45		11,655,544

Share-based compensation cost

	Years Ended August 31,
Stock compensation expense:	2021		2020
Selling, general and administrative	$	4,138,160	$	3,788,539
Research and development		649,838		1,084,371
Total	$	4,787,998	$	4,872,910

Stock options outstanding and exercisable

	Stock Options Outstanding			Stock Options Exercisable
Range of Exercise Prices	Number of Shares Subject to Outstanding Options	Weighted Average Contractual Life (years)	Weighted Average Exercise Price ($)	Number of Shares Subject To Options Exercise	Weighted Average Remaining Contractual Life (Years)	Weighted Average Exercise Price ($)
2.32	153,000	8.11	2.32	93,500	8.11	2.32
2.60	2,500,000	4.84	2.60	2,500,000	4.84	2.60
3.28	7,500	5.21	3.28	7,500	5.21	3.28
3.42	50,000	5.14	3.42	12,500	5.14	3.42
3.46	35,000	4.35	3.46	35,000	4.35	3.46
3.54	1,337,400	6.87	3.54	1,174,900	7.29	3.54
3.66	1,000,000	2.00	3.66	500,000	2.00	3.66
4.87	157,500	6.23	4.87	157,500	6.23	4.87
6.00	800,000	2.00	6.00	800,000	2.00	6.00
8.00	700,000	2.00	8.00	700,000	2.00	8.00
Total	6,740,400	4.29	3.97	5,980,900	4.45	4.02