Summary of valuation assumptions for stock options |
Black-Scholes assumptions used to calculate the fair value of options granted during the three and nine months ended January 31, 2021 and 2020 were as follows: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Three Months Ended January 31, | | Nine Months Ended January 31, | | | | 2021 | | 2020 | | 2021 | | 2020 | | | | | Expected term in years | 3 | | 3-6 | | 3-6 | | 3-6 | | | | | Risk-free interest rates | 0.12% | | 1.57%-1.80% | | 0.12%-0.39% | | 1.57%-1.80% | | | | | Volatility | 74.98% | | 69.14%-70.99% | | 72.64%-74.98% | | 69.14%-71.11% | | | | | Dividend yield | —% | | —% | | —% | | —% | | | | |
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Summary of stock option activity |
The Company’s stock options activity for the nine months ended January 31, 2021 was as follows: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Directors and Employees | Non- Employees | | | Total | | Weighted Average Exercise Price | | Weighted Average Remaining Contractual Life (Years) | | Aggregate Intrinsic Value | Outstanding, April 30, 2020 | 2,228,326 | | 43,332 | | | | 2,271,658 | | | $ | 3.23 | | | 5.0 | | $ | 10,663,000 | | Granted | 133,833 | | — | | | | 133,833 | | | 9.21 | | | 7.58 | | | Exercised | (662,285) | | (1,159) | | | | (663,444) | | | 2.27 | | | | | | Forfeited | (7,000) | | — | | | | (7,000) | | | 6.43 | | | | | | Canceled | (34,978) | | (923) | | | | (35,901) | | | 4.03 | | | | | | Expired | — | | (5,834) | | | | (5,834) | | | 10.80 | | | | | | | | | | | | | | | | | | Outstanding, January 31, 2021 | 1,657,896 | | 35,416 | | | | 1,693,312 | | | 4.02 | | | 5.66 | | $ | 11,975,000 | | | | | | | | | | | | | | Vested and expected to vest as of January 31, 2021 | 1,657,896 | | 35,416 | | | | 1,693,312 | | | 4.02 | | | 5.66 | | $ | 11,975,000 | | | | | | | | | | | | | | Exercisable as of January 31, 2021 | 1,289,104 | | 9,584 | | | | 1,298,688 | | | 3.25 | | | 4.93 | | $ | 10,173,000 | |
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