Summary of Significant Accounting Policies (Tables)

9 Months Ended

Feb. 29, 2020

Liability Measured at Fair Value on Recurring Basis by Level within Fair Value Hierarchy

Liabilities measured at fair value on a recurring basis by level within the fair value hierarchy as of February 29, 2020 and May 31, 2019 is as follows:

	Fair Value Measurement at February 29, 2020 (1)				Fair Value Measurement at May 31, 2019 (1)
	Using Level 3		Total		Using Level 3		Total
Liabilities:
Derivative liability—convertible note redemption provision	$	—	$	—	$	2,005,137	$	2,005,137
Derivative liability—warrants		2,108,398		2,108,398		402,132		402,132
Total liability	$	2,108,398	$	2,108,398	$	2,407,269	$	2,407,269

(1) The Company did not have any assets or liabilities measured at fair value using Level 1 or 2 of the fair value hierarchy as of February 29, 2020 and May 31, 2019.

Reconciliation of Liability Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)

The following is a reconciliation of the beginning and ending balances for liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the nine months ended February 29, 2020, and the year ended May 31, 2019:

Investor warrants issued with registered direct equity offering	$	4,360,000
Placement agent warrants issued with registered direct equity offering		819,200
Fair value adjustments		(3,855,468	)
Balance at May 31, 2018		1,323,732
Inception date value of redemption provisions		2,750,006
Fair value adjustments—warrants		(744,869	)
Fair value adjustments—convertible notes		(921,600	)
Balance at May 31, 2019	$	2,407,269
Fair value adjustments—warrants		4,110,363
Exercises —warrants		(2,404,097	)
Redemptions—convertible notes		(2,005,137	)
Balance at February 29, 2020	$	2,108,398