and $363,440 for each of the three and six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In July 2021, the Company granted stock options to purchase a total of 1,550,000 shares of common stock to its three executives pursuant to their respective employment agreements, the independent directors, and one consultant, pursuant to the Plan. The options were issued at an exercise price of $6.18, the grant date fair value, with one-quarter of the executive’s options vesting upon issuance and the balance over 36 months, and the options granted to the directors and consultants vesting over 36 months. The Company recorded general and administrative expenses of $490,916 and $981,833 for each of the three and six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In January 2022, the Company granted stock options to purchase a total of 80,000 shares of common stock to seven consultants pursuant to the Plan. The options were issued at an exercise price of $4.44, the grant date fair value, with one-quarter of the options vesting upon issuance and the balance over 36 months. The Company recorded general and administrative expenses of $18,950 and $37,900 for each of the three and six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In April 2022, the Company granted stock options to purchase a total of 30,000 shares of common stock to a new employee pursuant to the Plan. The options were issued at an exercise price of $3.79, the grant date fair value, with one-quarter of the options vesting upon issuance and the balance over 36 months. The Company recorded general and administrative expenses of $5,378 and $10,755 for each of the three and six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In February 2023, the Company granted stock options to purchase a total of 467,500 shares of common stock to its four employees and seven consultants pursuant to the Plan. The options were issued at an exercise price of $3.41, the grant date fair value, with the options vesting monthly over 36 months. The Company recorded general and administrative expenses of $109,521 for the three months ended June 30, 2024 and 2023, respectively, and $219,042 and $146,029 for the six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In June 2023, the Company granted stock options to purchase a total of 50,000 shares of common stock to its five independent board of directors pursuant to the Plan. The options were issued at an exercise price of $2.75, the grant date fair value, with the options vesting on the one-year anniversary of the grant date. The Company recorded general and administrative expenses of $26,800 and $0 for the three months ended June 30, 2024 and 2023, respectively, and $53,600 and $0 for the six months ended June 30, 2024 and 2023, respectively, related to compensation expense for these options.
In February 2024, the Company granted stock options to purchase a total of 835,000 shares of common stock to its four employees and a number of consultants pursuant to the Plan. The options were issued at an exercise price of $3.15, the grant date fair value, with the options vesting monthly over 36 months. The Company recorded general and administrative expenses of $183,713 and $244,951 for the three and six months ended June 30, 2024, respectively, related to compensation expense for these options.
In June 2024, the Company granted stock options to purchase a total of 60,000 shares of common stock to its five independent board of directors pursuant to the Plan. The options were issued at an exercise price of $2.38, the grant date fair value, with the options vesting on the one-year anniversary of the grant date. The Company recorded $0 for the three and six months ended June 30, 2024, respectively, related to compensation expense for these options.
Compensation expense associated with these awards is recognized over the vesting period based on the fair value of the option at the grant date determined based on the Black-Scholes model. Option valuation models require the input of highly subjective assumptions including the expected price volatility. The Company’s employee stock options have characteristics significantly different from those of traded options, and changes in the subjective input assumptions can materially affect the fair value computation using the Black-Scholes option pricing model. Because there is no public market for the Company’s stock options and very little historical experience with the Company’s stock, similar public companies were used for the comparison of volatility and the dividend yield. The risk-free rate of return was derived from U.S. Treasury notes with comparable maturities.