7.    Stock-Based Compensation

Total stock-based compensation expense for the three months ended December 31, 2022 and December 31, 2021 was $31,000 and $0.2 million, respectively. Total stock-based compensation expense for the nine months ended December 31, 2022 and December 31, 2021 was $0.1 million and $0.3 million, respectively.

Bionik granted options to purchase 244,000 and 273,500 shares of common stock to employees during the nine months ended December 31, 2022 and 2021, respectively. Stock options granted to employees or non-employees typically vest over a 1-to-5-year period.

The Company uses the Black-Scholes option pricing model to determine the estimated grant date fair values for stock-based awards. The Black-Scholes option pricing model requires the input of various subjective assumptions, including the option’s expected life and the price volatility of the underlying stock. The Company’s assumptions do not include an estimated forfeiture rate.

The weighted-average grant date fair values of options granted to employees during the nine months ended December 31, 2022 and 2021 were $0.30 and $2.05, respectively. All grants awarded during the periods presented used the following assumptions:

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Option-pricing models require the input of various subjective assumptions, including the option’s expected life and the price volatility of the underlying stock. As it relates to grants previously issued, Bionik’s estimated expected stock price volatility is based on past grants that have been made. Bionik’s expected term of options granted was derived from looking at the Company’s exercise history of its awards granted. The risk-free rate for the expected term of the options is based on the U.S. Treasury yield curve in effect at the time of the grant.

As of December 31, 2022 the total unrecognized compensation cost related to outstanding stock options expected to vest was $0.2 million, which the Company expects to recognize over a weighted-average period of 2 years.