WARRANT DERIVATIVE LIABILITY (Tables)

6 Months Ended

Jun. 30, 2020

WARRANT DERIVATIVE LIABILITY

Summary of key assumptions used to determine fair value of warrants

The following are the key assumptions that were used to determine the fair value of the 2019 Warrants:

	May 31,			June 30,
	2019			2020
Number of shares underlying the warrants		3,000,000			7,453,888
Fair market value of stock	$	0.95		$	0.40
Exercise price	$	1.30		$	0.40
Volatility		133	%		110	%
Risk-free interest rate		1.93	%		0.29	%
Warrant life (years)		5.00			3.92

Summary of the changes in the fair value of the warrant derivative liability

The following table sets forth a summary of the changes in the fair value of the warrant derivative liability, our Level 3 financial liabilities that are measured at fair value on a recurring basis:

	Three months ended				Six months ended
	June 30,				June 30,
	2020		2019		2020		2019
Beginning balance	$	3,162,733	$	—	$	4,620,593	$	—
Recognition of warrant derivative liability on May 31, 2019		—		2,416,422		—		2,416,422
Warrant exercise		(821,538)		—		(903,779)		—
Change in fair value of warrants derivative liability		4,541		(401,862)		(1,371,078)		(401,862)
Ending balance	$	2,345,736	$	2,014,560	$	2,345,736	$	2,014,560