On September 25, 2017, we issued 27,943 shares of our Junior Convertible preferred stock to SVB Financial Group upon the cashless exercise of a warrant to purchase 40,000 shares of our Junior Convertible preferred stock at an exercise price of $1.00 per share, based on a fair market value of $3.3175 per share as determined under the terms of such warrant.
(b) Option and restricted stock unit issuances
Since January 31, 2016, we have granted to employees, officers, directors, consultants and other service providers options to purchase an aggregate of 1,384,000 shares of our common stock, with exercise prices ranging from $1.16 to $1.57 per share, pursuant to the 2006 Plan. The 2006 Plan expired on August 30, 2017. Since January 31, 2016, 1,237,643 shares of common stock have been issued upon the exercise of stock options pursuant to the 2006 Plan, at exercise prices between $0.31 and $1.57 per share, for an aggregate exercise price of $593,392.74.
Since the adoption of the 2018 Plan by our board of directors on February 2, 2018 and stockholders on June 22, 2018, we have granted stock options to purchase an aggregate of 6,104,417 shares of our common stock, with exercise prices ranging from $2.14 to $5.41 per share, to employees, officers, directors, consultants and other service providers pursuant to the 2018 Plan. Since the adoption of the 2018 Plan, 3,458 shares of common stock have been issued upon the exercise of stock options pursuant to the 2018 Plan, for an aggregate exercise price of $7,400.12.
Since the adoption of the 2018 Plan, we have granted an aggregate of 987,500 restricted stock units to be settled in shares of our common stock to employees, officers, directors, consultants and other service providers pursuant to the 2018 Plan.
(c) Warrants to purchase capital stock
On November 7, 2016, we issued to Silicon Valley Bank a warrant to purchase up to 196,570 shares of our common stock at an exercise price of $1.59 per share.
On November 7, 2016, we issued to Escalate Capital Partners SBIC III, LP a warrant to purchase up to 336,280 shares of our Senior A preferred stock at an exercise price of $3.00 per share.
On November 7, 2016, we issued to Orix Finance Equity Investors, LP a warrant to purchase up to 336,280 shares of our Senior A preferred stock at an exercise price of $3.00 per share.
On February 28, 2019, we issued Silicon Valley Bank a warrant to purchase up to 165,100 shares of our common stock at an exercise price of $3.65 per share.
On February 28, 2019, we issued WestRiver Innovation Lending Fund VII, L.P. a warrant to purchase up to 165,100 shares of our common stock at an exercise price of $3.65 per share.
None of the foregoing transactions involved any underwriters, underwriting discounts or commissions, or any public offering. We believe that such transactions were exempt from the registration requirements of the Securities Act, including Regulation D and Rule 506 promulgated thereunder, by virtue of Section 4(a)(2) of the Securities Act because the issuance of such securities to the recipients did not involve a public offering, or in reliance on Rule 701 because the transactions were pursuant to compensatory benefit plans or contracts
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