INTANGIBLE ASSETS, NET

12 Months Ended

May 31, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets Disclosure [Text Block]

3.    INTANGIBLE ASSETS, NET

Intangible assets, net of accumulated amortization, consist of the following at May 31:

	2020		2019
Licenses	$	551,397	$	510,600
Patents		113,382		68,860
Less accumulated amortization- licenses		(487,989)		(471,530)
Less accumulated amortization- patents		(8,135)		(721)
Intangible assets, net	$	168,655	$	107,209

Expected amortization of intangible assets for the years ending May 31:

2021	$	18,112
2022		8,503
2023		6,211
2024		6,136
2025		5,219
Thereafter		124,474
Total	$	168,655