Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Warrants

v3.20.2
Fair Value of Warrants
9 Months Ended
Sep. 30, 2020
Fair Value Disclosures [Abstract]  
Fair Value of Warrants Fair Value of Warrants
The following table summarizes the derivative warrant activity subject to fair value accounting for the nine months ended September 30, 2020 (in thousands):
Issued with/for Fair value of warrants
outstanding as of
December 31, 2019
Change in fair
value of warrants
Fair value of warrants
outstanding as of
September 30, 2020
2016 Offerings $ 178  $ (133) $ 45 

The derivative warrants issued as part of the 2016 Offerings are valued using a probability-weighted Binomial model. The following tables summarize the assumptions used in computing the fair value of derivative warrants subject to fair value accounting at September 30, 2020 and December 31, 2019.
2016 Offerings As of September 30, 2020 As of December 31, 2019
Exercise price $ 67.50  $ 67.50 
Expected life (years) 1.33 2.08
Expected volatility 164.40  % 150.69  %
Risk-free interest rate 0.12  % 1.58  %
Expected dividend yield —  % —  %